Real Submarine Technology & History Q&A

[Stormende]

Davey, I have more questions for you that I hope you can answer, plz.

If the American torpedoes were that bad at the beginning of the war, how come the kill ratio between surface vs submerged vessels favored the subs?

How often did the submarines use their deck guns and how effective they were?

Were the English torpedoes better (reliable) than the Americans ?

Well that will be all for now, thankx in advance!

:up:

[DaveyJ576]

If the American torpedoes were that bad at the beginning of the war, how come the kill ratio between surface vs submerged vessels favored the subs?

You have to remember that for most of the first year of the war, submarines were the only contingent of our armed forces that were effectively carrying the hurt to the enemy. Everything else was sidelined or distracted into defensive actions. Submarines were out there making offensive patrols, seeking out and engaging enemy vessels from day one and didn't stop until the last day of the war. Our surface forces (destroyers, cruisers, and battleships) didn't enter into combat against other ships until the Guadacanal campaign in August 1942, and even then when boiled down to pure numbers, we lost more ships than the Japanese did in the Solomons. The surface forces were tasked with seeking out and destroying the relatively sparse IJN fleet units, leaving submarines and the air forces to engage the more numerous merchant vessels. They simply had more targets to shoot at and therefore the kill ratio favored the boats.

Yes, our torpedoes sucked initially, but they did work some of the time, often enough for aggressive and skilled skippers like Chester Smith, Mush Morton, and Creed Burlingame to put some ships on the bottom.

How often did the submarines use their deck guns and how effective they were?

There is a rather romantic vision in many people's minds of submarines engaging in heated gun battles with merchant vessels. From the American side at least, this actually was pretty rare. The 3" and 4" guns that were carried by the boats in the first two years of the war lacked sufficient punch to dispose of a merchant vessel quickly enough to warrant the danger of exposing the boat to counter attack. Therefore their usage quickly evolved to finishing off cripples (even this was fairly uncommon) and destroying sampans and small coastal luggers. It wasn't until the appearance of the 5"/25 cal gun in the last year of the war that the boats had an effective and fairly powerful gun. However, by this time the torpedo problems had been solved and there was even less incentive to risk your boat in a surface gun battle.

Without a stable element and centralized fire control, accuracy from the pitching and heaving deck of a submarine was poor even under good conditions. You ended up expending a lot of rounds (when misses were figured in) to sink a decent sized vessel, and this took too much time for most skippers.

Submarines are not tolerant of holes in the pressure hull. One small hole and assuming you don't sink, your patrol is over right there and you head home. It is fairly easy to punch a hole in a submarine and disable it, but even a moderate size merchant ship with all its reserve buoyancy can absorb a comparitively large amount of damage and not sink. Therefore the odds favor the merchant ship in a gun battle.

Were the English torpedoes better (reliable) than the Americans ?

Comparitively speaking, British torpedoes were mechanically more reliable than their American or German counterparts. The RN conducted an exhaustive series of firing trials on the China station prior to the war and were thus able to work out most of the bugs. However, the RN also fell prey to the siren-song lure of the magnetic influence exploder. Theirs didn't work any better than the ones used by the USN and the Kriegsmarine and the last of them were not discarded until late 1944.

[Stormende]

Thankx again for the answers, Davey.

:up:

[Mikeb213]

Hey guys, I am new here but have been reading through this amazing set of posts. I had an idea and wanted to see what you guys would think of this. I am really interested in comparing the sub tech between the major players in wwII both before and after the war. I really want to see the specs of German, Jap, and American subs to see where they all were and what they ended up with by the end of the war. Do you guys have any ideas where we could get the specs for the best boats they had at the start of the war, and the best by the end?

Thanks!
Mike

[Sensekhmet]

That would be a pretty simplistic comparison, don't you think? For example, the XXI would probably come out on top as 'the best' but in reality it saw little to no action, and its impact on the conflict was according.

[Deamon]

I am a Chief Petty Officer in the United States Navy and a qualified submarine sailor. I served aboard the USS Darter SS-576 during the Cold War, a diesel boat very similar to the fleet boats played in SHIV. I am also the co-founder and author of a submarine history website.
Interesting!

Dave, what all were your fields of competence ?

[Deamon]

That is one of the best posts I have read here at SUBSIM Davey :yep::up:
I second that. 5/5 post and 5/5 thread!!!

A sub officer willing to discuss the matter, priceless!!! This thread goes right into my bookmarks!

[Mikeb213]

Hey Dave question for you....so in many books I have read about subs in WWII they said it would get very hot once they would dive. Had they fixed the air conditioning systems so it would stay comfortable by the time you served?

[DaveyJ576]

I am really interested in comparing the sub tech between the major players in wwII both before and after the war. I really want to see the specs of German, Jap, and American subs to see where they all were and what they ended up with by the end of the war. Do you guys have any ideas where we could get the specs for the best boats they had at the start of the war, and the best by the end?

The term "best" is extraordinarily subjective. It really depends on which attributes you consider to make a submarine the best. Speed? Range? Torpedo loadout? Diving depth?

Each country's submarines were designed with a specific mission and a specific set of operating parameters in mind. The American fleet boats were designed for long range, long endurance patrols in the warm Pacific. These requirements really drove the design. The Germans, British, and Dutch (among others) all produced excellent boats that were uniquely tailored to the missions that their countries needed them to do.

Submarine design is an evolution in compromise. The state of the art in the 1930's and 40's did not allow anyone to build the perfect all around submarine. It is necessary to sacrifice some performance characteristics in order to get others. To obtain long range, for instance, the boat had to be large in order to be able to carry enough fuel. A large boat is going to dive slower than a smaller boat, and it will have a wider turning circle. To get high speed, you have to have a battery with a very high voltage output. But these types of batteries take longer to charge, they produce high amounts of explosive hydrogen during charging, and they wear out quicker making them much more expensive and maintenance intensive. See the point?

This type of discussion has occurred before in these forums and it ended up being pointless. Every country that had submarines produced some excellent designs. Some of these boats were good in some areas and less than optimal in others. You can argue the various merits of each boat ad nauseum and get no where because it boils down to each person's opinion.

I can recommend several resources that you can go to in order to find the data you are seeking, and then you can make up your own mind. I will be happy to answer any questions you may end up having, but my area of expertise is the American boats. Some of the other participants of these forums are more knowledgeable about the other country's subs. Those resources include:

The Fleet Submarine in the U.S. Navy by John D. Alden (ISBN 0-85368-203-8)

Cold War Submarines by Norman Polmar & K.J. Moore (ISBN 1-57488-594-4)

U.S. Submarines Through 1945 (ISBN 1-55750-263-3) and U.S. Submarines Since 1945 (ISBN 1-55750-260-9) by Norman Friedman. Please see the note of caution about this author's books in a post above.

The Underwater War 1939-1945 by Richard Compton-Hall (ISBN 0-7137-1131-0). I would also caution the reader about this book. Mr. Compton-Hall is an excellent and knowledgeable author, but has a strong anti-American bias that colors what he writes.

Pigboats.com by Ric Hedman and Dave Johnston (www.pigboats.com (http://www.pigboats.com))

Uboat.net by Gudmundur Helgason (www.uboat.net (http://www.uboat.net))

[DaveyJ576]

Interesting!

Dave, what all were your fields of competence ?

To answer that question I will direct you to the following page:

http://pigboats.com/davebio.html

[DaveyJ576]

In many books I have read about subs in WWII they said it would get very hot once they would dive. Had they fixed the air conditioning systems so it would stay comfortable by the time you served?

In most submarines, the air conditioning systems weren't broken, they just didn't exist!! Air conditioning was a new technology in the 1930's and 40's and was looked upon as an unnecessary luxury in most navies. Most of the world's submarines did not have any sort of air cooling or dehumidification systems at all until after the war.

The USN had a requirement of conducting long duration patrols in the warm waters of the Pacific Ocean. In the closed environment of a submarine in warm waters, condensation was a huge problem. The condensate dripped into electrical systems and caused constant shorts and fires. It also caused mold, mildew, and heat rash problems for the crew. Seeking a way of mitigating this problem, the USN installed the first air conditioning system in the USS Cuttlefish (SS-171) in 1934. The experiment was entirely successful and A/C systems were installed or retrofitted to all subsequent submarines. These systems were mainly intended for de-humidification, but had the pleasant side effect of cooling the air. This proved to be a key factor in the mechanical reliability of the USN fleet boats.

Those early systems were quite noisy however, and were quickly shut down during evasion to avoid giving away the boat's position to enemy sonars. This is what you were reading about.

A/C systems are of a benefit in any operating theater, but curiously few of the other navies installed them in their boats. This resulted in the sometimes deplorable living conditions that were very accurately portrayed in Das Boot.

[Stealhead]

Nice bio Davey.:up:

Could you go over the histroy of the dreaded circle run that could occur with the mk.14 and mk.18 tropedos?

[DaveyJ576]

Could you go over the history of the dreaded circle run that could occur with the mk.14 and mk.18 torpedoes?

Circular torpedo runs were a dangerous and frustrating problem for our submarines, but it did not occur with the frequency of the other problems. There was a great deal of debate as to what was the exact cause of the circular runs. Some claimed it was mechanical in nature, others pointed to tactics.

The material that was used in the manufacture of the rudder posts was discovered to corrode rather easily. After the fish left the tube and the gyro swung the rudder to turn the fish it to its preassigned heading, the rudder could jam in that position due to the corrosion on the rudder posts. It was a practice of the time to flood the tubes and open the outer doors well in advance to save time in the firing sequence. This tended to exacerbate the corrosion problem. Once it was realized what was happening, the practice was changed to flooding the tube and opening the outer doors only just before firing, keeping the fish dry as long as possible. There was also a renewed emphasis on proper and careful maintenance of the fish prior to firing.

Later production runs of both types of torpedoes corrected this problem by substituting a corrosion resistant metal in the construction of the rudder posts.

Another possible cause of circular running was forcing the fish to turn too far by putting a large gyro angle setting on it. The gyro would hit its stops and tumble. USN skippers came to favor shots that used little or no gyro angle setting and this helped to mitigate the problem

The Mk. 18 Mod 1 electric torpedo was rushed into production and was very buggy. It suffered terribly from corroded rudder posts among other problems and circular runs were a big issue. For once, feedback from the fleet was listened to and the Mk. 18 Mod 2 corrected most of the problems, but was not available until late in the war.

After the war, with the advent of homing torpedoes, an anti-circular run device was built into the control electronics of all torpedoes. This device would shut down the fish if it detected a turn of more than 180 degrees from the original firing heading.

[Mikeb213]

Hey Dave,
When you would go out for patrol did you guys go through Angles and Dangles? Since there was not a war on at the time did you guys have to go down to or below test depth a lot?
Thanks!

[Stealhead]

Thanks Davey for the torpedo reply.

The Fleet Submarine in the U.S. Navy by John D. Alden (ISBN 0-85368-203-8) is a great book but a heads up it is very rare and out of print so I would go for a used copy which can be had for around $40.00 at Amazon.
Most sites are asking $160.00 for an uncirculated copy.:o

The aurthor served on fleet boats during and after the war and he wrote the book to answer some of his own questions about fleet boat design.It also covers the post war GUPPY and Fleet Snorkel programs.

[DaveyJ576]

Hey Dave,
When you would go out for patrol did you guys go through Angles and Dangles?

Aaahhh, angles and dangles. This is the closest thing to an amusement park ride you can get on a submarine. It was a lot of fun with a strong hint of danger.

Angles and dangles was the process of putting the boat through rather large up and down angles while changing depth. We would at times get as high as 35 degrees. The angle indicator bubble gauge in the Control Room stopped at 45 degrees and we tried to keep it well below that. Anything greater and you risked spilling the battery acid and that would cause a lot of problems.

The planesmen and the Diving Officer had to be pretty careful because you could go out of control pretty quick. If you lost it going up you could broach and risk a collision. If you lost it going down...well, I think you could guess what happens.

One of our skippers liked to pull a large down angle on our first dive after leaving port. It was his method to see if the boat was neat, squared away, and stowed for sea. If it wasn't, anything that wasn't stowed properly would go flying, and if you weren't holding on, so would you.

One day when we were down deep, one of our cooks wanted to bake an angel food cake. He poured the batter in the pan and called up to the Diving Officer to see if we were going to change depth. Assured by the Dive that we were staying right where we were at, he opened the oven and put the cake in. Sure as hell, five minutes later we angled up and headed to periscope depth. You could hear the cursing throughout the whole boat as the cook looked in the oven and found all the batter run to the back end of the pan and sloshed over, creating a huge mess in his oven. Royally pissed, he let it bake and when it was done he took it out. The remainder of the batter had baked in the aft end of the pan and had a nice slope down to the center, where it smoothly tapered to nothing in the front end of the pan. He threw some frosting on it, set it on the table, and called it "Angle Food Cake"!!

Since there was not a war on at the time did you guys have to go down to or below test depth a lot?

We could go to test depth anytime operations required it. There were no restrictions. However, one thing you NEVER did was exceed test depth for any reason. After losing the Thresher, the submarine force was a little sensitive about that. If you exceeded test depth all sorts of messages had to be sent explaining why. All systems exposed to sea pressure had to be tested by a shipyard to ensure they weren't damaged. To say that it involved a lot of paperwork is a monumental understatement. As a matter of fact, we usually stayed about 10 feet above test depth just to make sure.

On my old Darter, though, we spent 80% of our submerged time at depths less than 300 feet. By 1986 she was 30 years old and if there was no reason to push the envelope, then we didn't.

[Mikeb213]

Hey Davey,
Another questions for you. I would be willing to bet that you spent some time doing simulated wargames ect. how would you decide when a target had been destroyed? Did you guys have to play against nuke subs very often? I have heard that in a lot of cases a diesel sub can be a lot more silent then a nuke is this true? How would a diesel sub be used to stalk a nuke?

Mike

[DaveyJ576]

I would be willing to bet that you spent some time doing simulated wargames ect. how would you decide when a target had been destroyed?

We would make our approach and once we reached firing point, we would launch a flare from our signal launcher (essentially a mini torpedo tube pointed upwards). Once the flair was sighted, the skimmer target was dead. Our weapon was the Mk. 48 Mod 3 torpedo, which at the time was the most capable and deadly torpedo in the world. Once you launched one, your target was dead, no joke.

Did you guys have to play against nuke subs very often? I have heard that in a lot of cases a diesel sub can be a lot more silent then a nuke is this true? How would a diesel sub be used to stalk a nuke?

I will refer you back to post #238. A diesel sub, when running on the battery and rigged for ultra-quiet, can be extremely quiet. Virtually no noise is radiated into the water due to the nature of its propulsion system.

On the Darter, we did an exercise once with the USS Bremerton (SSN-698). She did get us, but had one hell of a difficult time doing it. We received several compliments from her CO for being so quiet. This was for a diesel boat that was 30 years old at the time. Think what a modern boat can accomplish.

However, do not make the mistake in thinking that a nuke boat is at a disadvantage. A Virginia class SSN or Ohio Class SSBN is actually quieter than the ambient noise in the surrounding ocean. To detect it (if that is actually possible) you would have to listen for the area of the ocean that is quieter than the rest, not the noisiest!!!

[Arclight]

Looking for the hole in the water. :yep:

[Mikeb213]

Back then on Darter, I can't remember for sure but weren't the 688s using the BSY-1 suite at the time? Did they have anything like that retro fitted on to the diesel boats? Did they place a towed sonar array on board also? Sorry for all the questions I have spent years reading about this history of subs from wwII through the cold war and never had a chance to really ask the questions I wanted to ask. So thank you for your patience I really enjoy learning about this.

Mike

[Buddahaid]

I want to get your thoughts about what I understand regarding the danger of high angle, high speed emergency blows. The risk involves after breaking surface, the possibility of sliding backwards instead of the bow dipping and the boat leveling off. If it were to slide back, the ballast tanks would take on a lot of sea, causing a heavy boat with a large angle. Thus leading to an uncontrolled dive and disaster. I think this was tested and the maneuver banned as to risky.

Buddahaid

[DaveyJ576]

Back then on Darter, I can't remember for sure but weren't the 688s using the BSY-1 suite at the time? Did they have anything like that retro fitted on to the diesel boats? Did they place a towed sonar array on board also?

The highly advanced and capable AN/BSY-1 integrated combat system premiered with the USS San Juan (SSN-751) in 1988. Earlier units of the Los Angeles class were equipped with the still potent BQQ-5 and 5E systems. None of these systems were retrofitted into diesel submarines. There were several reasons behind this.

1. The remaining combat capable diesel boats, Darter, Barbel, Blueback, and Bonefish were just not large enough to handle the new displays in their sonar rooms.

2. These new systems all used a large, spherical, bow mounted sonar array. All four boats had bow mounted torpedo tubes that made them incompatible with this array.

3. These systems used an enormous amount of power. None of the diesel boats could produce enough sustainable electricity to power the systems.

4. By 1988 the diesel boats were 30 years old and while still very useful, were not worth such a massive upgrade, even if it were feasible. Darter and Barbel were decommissioned in 1989, Blueback in '90, and Bonefish in '88.

Towed array systems, while very useful, were again not very compatible with the older submarines. The Submarine Towed Array Sonar System (STASS) was installed for a brief time on at least Darter and Barbel. It gave us some good data, but it was a pain in the butt operationally. It was a "clip-on" system that sat exposed on the after deck. It was coiled by hand around several stanchions and had to be deployed and retrieved by hand (what we called the "Armstrong Engineering Method" :D) while on the surface. If the sea was too rough to send someone topside to retrieve it, we couldn't go into port. That delayed a liberty run to Hong Kong once and the crew was pretty pissed. We eventually beached the system and the Darter finished her service without it.

[DaveyJ576]

I want to get your thoughts about what I understand regarding the danger of high angle, high speed emergency blows. The risk involves after breaking surface, the possibility of sliding backwards instead of the bow dipping and the boat leveling off. If it were to slide back, the ballast tanks would take on a lot of sea, causing a heavy boat with a large angle. Thus leading to an uncontrolled dive and disaster. I think this was tested and the maneuver banned as to risky.

I am not sure were you are getting your information, but unfortunately none of it is correct.

Emergency blow systems were retrofitted to all USN submarines following the Thresher disaster in 1963. These systems are designed to rapidly surface a submarine in the event of flooding or other trouble. 3000 psi air is rapidly fed into the main ballast tanks, almost instantly emptying them (even down to test depth). This sends the boat up like a rocket with a large up angle.

A submarine is rarely, if ever, at a dead stop while submerged. It will always have at least some forward momentum. This momentum will cause it to continue to move forward after it breaks the surface, thus negating any possibility of sliding backwards. Even if it were at a dead stop, the act of conducting an emergency blow will give it some forward momentum.

Obviously, in order to conduct an emergency blow the main ballast tank vents have to be shut. This will trap the air inside of the tanks and prevent it from escaping. True, if the boat were at a 90 degree angle (i.e. vertical) and slid backwards into the sea it would lose a lot of the trapped air. But this never happens. As long as the crew has at least some control of the boat, they will control the angle using the stern planes and keep it to less than a 45 degree angle (usually only about a 30 degree angle at most). Combined with the aforementioned forward momentum this will keep enough air in the tanks to keep the boat on the surface.

See these links for what I am talking about:

http://www.navsource.org/archives/08/0876205.jpg

http://www.navsource.org/archives/08/0871912.jpg

Notice that in both photos the angle is fairly shallow, probably not more than 25 degrees. Also notice that the boat is really moving forward and will not slide backwards.

I will grant you that the situation that you described is theoretically possible, but it is extraordinarily unlikely to happen. Procedures and crew action alone preclude it from happening.

Emergency blows are a routine part of training for all USN submarine crews and are done on a regular basis. I personally participated in about 12 of them in the three years I was on the Darter. It is true that the maneuver is dangerous, mostly from collision at or near the surface. But with proper controls, those risks can be mitigated.

[Buddahaid]

OK. I got the story from Dad who worked at Mare Island and was on sea trials, and is in reference to the Gato, or similar types, rising at a very high angle and speed, allowing the open undersides of the ballast tanks to spill air. It may not involve an emergency blow, and unfortunately I don't have any details, but I understood it was testing how high an angle could be safely used. Thanks for the response.

Buddahaid

[DaveyJ576]

OK. I got the story from Dad who worked at Mare Island and was on sea trials, and is in reference to the Gato, or similar types, rising at a very high angle and speed, allowing the open undersides of the ballast tanks to spill air. It may not involve an emergency blow, and unfortunately I don't have any details, but I understood it was testing how high an angle could be safely used. Thanks for the response.

Buddahaid

Back in the 50's and 60's there was all sorts of testing going on to determine the maximum operating parameters of our boats. I don't doubt for a minute that the tests your dad described took place. However, keep in mind that these were tests and the boat was deliberately put in an out of control condition (this is extremely dangerous by the way). Anything approaching "normal" conditions would have the boat under control by the crew and the angle of the surfacing strictly regulated.

Check out the following photo of the USS Pickerel (SS-524) During an surfacing drill on 01 March 1952.

http://www.navsource.org/archives/08/0852403.jpg

This is not a true Emergency Surface as she did not have the system at the time. However, she started at 250 feet and flank speed. The planesmen were ordered to take a 60 degree up bubble. They lost control at 65 degrees and the boat hit 72 degrees (Holy Crap!!) just prior to breaking the surface. This is the unofficial record for an up angle on surfacing.

The only thing I would question about your account of the tests is about losing air out of the ballast tanks. With the vents shut, the air is going to be trapped inside the tanks. It will not spill out the bottom. Any remaining residual water will, but the air won't. The only time that would happen is if the boat was at a 90 degree angle or greater. Anything less than that and the air would remain trapped inside the tanks as the boat settled back into the water.

Take a look at the following video of a 688 doing an Emergency Blow:

http://www.youtube.com/watch?v=lxyMzR9K1Dk&feature=PlayList&p=BBA025591C90D8F8&index=0

Notice the angle of the boat and how far it settles back into the water afterward. Even still, it promptly pops back up to the surface.

[Buddahaid]

Yup that USS Pickerel shot is what I'm referring to.

Thanks again.
Buddahaid

[Mikeb213]

Hey Davey,
So can you really take a piece of string and tape it to either side of the hull in a sub, and as it goes down deep does the hull compress that much that it would make the string droop?

[Deamon]

3000 psi air is rapidly fed into the main ballast tanks, almost instantly emptying them (even down to test depth).
I am wondering what almost instantly means here, do the ballast tanks get emptied faster than they get filled during crash dive ?

[Mikeb213]

Davey another question too, I just saw that the Dolphin was made into a museum, and that it can dive so deep that the dive info is still restricted. The only info they gave was that it was over 3000 feet. If you did an emergency blow that deep, is there a speed the sub reaches that it tops out at? I know when I used to play the game 688i if I was running deep and trying to evade a torpedo at the last few seconds before I got taken out I would try and do an Eblow and I would get a burst of speed that would put me over 45knots. Can't you damage the ship coming out of the water that fast on the slam down?

[DaveyJ576]

Hey Davey,
So can you really take a piece of string and tape it to either side of the hull in a sub, and as it goes down deep does the hull compress that much that it would make the string droop?

I can verify that it will actually do that. You can't visibly see the hull compress, but it surely does.

The doors going into the heads are non-watertight aluminum doors that sit inside of a frame, very similar to what you would find in any house. On the surface, the doors open and shut freely with a minimal amount of force. Once you go deep, the hull compresses enough to warp the door frame out of square and compress it against the door. You could open the door with one finger on the surface, but now it requires a pretty good tug with both hands.

You also have to be very careful when flushing the toilets. They are flushed with seawater and on the surface you get a nice flow into the bowl with just enough pressure to flush the contents. Down deep, you just barely crack the valve and you get a Niagara Falls flow that if you are not damn careful could flood the whole head! :D

[DaveyJ576]

I am wondering what almost instantly means here, do the ballast tanks get emptied faster than they get filled during crash dive ?

Perhaps it was a poor choice of words. I should have used "very rapidly" as opposed to "almost instantly".

On the Darter, an emergency blow would empty the tanks in about 2-3 seconds from 200 feet. I never did one from test depth, but it would take a little longer due to the much higher sea pressure. I would estimate probably 10-12 seconds. A normal surfacing blow of 1500 psi would empty the tanks in about 5 seconds from periscope depth (48 feet).

[DaveyJ576]

Davey another question too, I just saw that the Dolphin was made into a museum, and that it can dive so deep that the dive info is still restricted. The only info they gave was that it was over 3000 feet. If you did an emergency blow that deep, is there a speed the sub reaches that it tops out at? I know when I used to play the game 688i if I was running deep and trying to evade a torpedo at the last few seconds before I got taken out I would try and do an Eblow and I would get a burst of speed that would put me over 45knots. Can't you damage the ship coming out of the water that fast on the slam down?

Damaging a sub with excessive speed is definitely possible. A submarine is like an airplane in that respect. Go too fast and the aerodynamic (or hydrodynamic) forces will eventually exceed the ability of the structure to resist it and it will break apart. What that point is for a submarine I have no idea and I do not want to find out. The marine engineer who designed it would have to provide the answer.

As a point of reference, the Space Shuttle Challenger was not destroyed in an explosion. True, the External Tank exploded due to flame impingement from a O-ring leak-by from one of the Solid Rocket Boosters. But the Challenger herself was destroyed when the explosion forced it out of its normal flightpath. The aerodynamic loads exceeded their limits and she instantly broke up. What most people don't realize is that during the first two minutes of ascent, the space shuttle is operating at the very limits of structural strength. Only the slightest deviation from its programmed flightpath is necessary to cause it to break up.

[Mikeb213]

Davey, how would they control the speed of ascent on a eblow from very deep?

[DaveyJ576]

Davey, how would they control the speed of ascent on a eblow from very deep?

You will gain some speed on the way up, but not a lot. Even from test depth you might pick up only 5 knots or so. But if you had to reign in the speed you would simply back down on the propeller (properly called a screw).

[Mikeb213]

Dave,
What do they do to prepair a ship for becoming a museum? I have seen at least one that looked like it was ready to sail, and had working engiens. The Pampinito in San Francisco is a very good example. Can they still sail under there own power? Is it possible to still dive one of the subs? How about the aircraft carriers? Do they remove the engiens so it can't move? Could they be put back into service?

[Deamon]

Dave, I am wondering how big is your interest in the WWI portion of the submarine history ?

[DaveyJ576]

Dave,
What do they do to prepair a ship for becoming a museum? I have seen at least one that looked like it was ready to sail, and had working engiens. The Pampinito in San Francisco is a very good example. Can they still sail under there own power? Is it possible to still dive one of the subs? How about the aircraft carriers? Do they remove the engiens so it can't move? Could they be put back into service?

Any equipment that is currently used by the Navy and is in good shape is removed for reuse and put back into the Navy supply system. All fluids are drained (hydraulic, lube oil, fuel oil, potable water, battery water, etc.). All other hazardous materiels are removed and disposed of. Off course, all ammunition, including torpedoes are sent ashore to a magazine. The propellers are removed from the shafts. The electrical system is scoured for salvageable metals, rendering it incapable of being used.

The biggest change is that the batteries are removed. This alone prevents the boat from ever being used again operationally. The batteries are probably the most maintenance intensive item on a submarine and their care and upkeep would be well beyond the limited resources of any museum.

It is true that several of the boats have working engines. The Fairbanks-Morse and GM-Winton diesels were hardy and robust engines and with a moderate amount of care will run forever. Parts are fairly plentiful and getting one operational would not be difficult or overly expensive. However, with the electrical system gutted and the screws removed, using these engines to provide propulsion is nothing but a dream.

For a private organization to put one of these boats into service and take it back to sea would be a monumentally daunting task, to put it mildly. The financial requirements alone would be light years beyond the capability of a privately funded museum. Even if you could fix all the gear and get everything running again, you have to remember that the Navy decommissioned these boats because they were no longer serviceable. They had been run hard during their service lives and were plain worn out. Thousands of compression/expansion cycles from diving and stresses put on the hull from decades of heavy seas leads to severe metal fatigue. Welded joints weaken, the hull dimples in between frames, and corrosion becomes a major concern.

I would also imagine that getting all the proper Coast Guard certifications for operation would be virtually impossible.

These boats make fine memorials and teaching tools for the public, but their days of going to sea are over, most unfortunately.

Making one of the carriers operational again would be an even more difficult task, if that is possible. Steam plants are very dangerous to operate once they are worn out. Making the hundreds of miles of steam piping and the thousands of valves operational again would be virtually impossible for a private organization.

[DaveyJ576]

Dave, I am wondering how big is your interest in the WWI portion of the submarine history ?


I am interested in all eras of submarine history and technological development. Each era has its interesting stories and I enjoy watching the progress of the technology as you move through the years.

I would consider my area of expertise to be the USN submarines, with a focus on the WWII era. I have a good working knowledge of the other country's boats, but I usually defer to other experts once the discussion moves in this direction.

[snakeyez]

Any equipment that is currently used by the Navy and is in good shape is removed for reuse and put back into the Navy supply system. All fluids are drained (hydraulic, lube oil, fuel oil, potable water, battery water, etc.). All other hazardous materiels are removed and disposed of. Off course, all ammunition, including torpedoes are sent ashore to a magazine. The propellers are removed from the shafts. The electrical system is scoured for salvageable metals, rendering it incapable of being used.

The biggest change is that the batteries are removed. This alone prevents the boat from ever being used again operationally. The batteries are probably the most maintenance intensive item on a submarine and their care and upkeep would be well beyond the limited resources of any museum.

It is true that several of the boats have working engines. The Fairbanks-Morse and GM-Winton diesels were hardy and robust engines and with a moderate amount of care will run forever. Parts are fairly plentiful and getting one operational would not be difficult or overly expensive. However, with the electrical system gutted and the screws removed, using these engines to provide propulsion is nothing but a dream.

For a private organization to put one of these boats into service and take it back to sea would be a monumentally daunting task, to put it mildly. The financial requirements alone would be light years beyond the capability of a privately funded museum. Even if you could fix all the gear and get everything running again, you have to remember that the Navy decommissioned these boats because they were no longer serviceable. They had been run hard during their service lives and were plain worn out. Thousands of compression/expansion cycles from diving and stresses put on the hull from decades of heavy seas leads to severe metal fatigue. Welded joints weaken, the hull dimples in between frames, and corrosion becomes a major concern.

I would also imagine that getting all the proper Coast Guard certifications for operation would be virtually impossible.

These boats make fine memorials and teaching tools for the public, but their days of going to sea are over, most unfortunately.

Making one of the carriers operational again would be an even more difficult task, if that is possible. Steam plants are very dangerous to operate once they are worn out. Making the hundreds of miles of steam piping and the thousands of valves operational again would be virtually impossible for a private organization.

Just had to say, nice answer there Dave. It seems that each museum sub has slightly different things done to them. I think even the ballast tank vents are welded over.

There various working parts in many of the museum subs, while enhancing in realism, are far from making any of them ready for sea again. Most of them aren't even safe for towing across the open sea. :) I keep hearing rumors of the Pampanito being a licensed operational surface craft, but haven't learned the whole truth as of yet.

[Mikeb213]

So in the case of the Pamp, would they be allowed to have an operational radar, sonar, radio from WWII? Even if the ship has to sit, are there rules against those being brought back into full operational condition?

[snakeyez]

So in the case of the Pamp, would they be allowed to have an operational radar, sonar, radio from WWII? Even if the ship has to sit, are there rules against those being brought back into full operational condition?

Mike,

I don't think the Navy cares as long as they don't have to supply anything, material or monetary. The Cobia has operational radar. There are licenses to get for operational equipment like radio.

Take a look at this year's checklist. This is what the Navy requires annually at checkup time.

http://www.submarinemuseums.org/pics/misc/SDIPChecklistFY09.pdf

[Sensekhmet]

Well, on the topic of making museum relics 'live' again... I've read once it's easier to get back a WW2 armored vehicle back to full operation if you're working with a wreck pulled out of a bog or a river bed than an ex-memorial or a museum item! The reason being exactly the same as in submarines, 99% of these memorials or museum objects are just stripped out empty shells, with some bad welding and sometimes being simply structurally unsound.

[Mikeb213]

I read that they were keeping the Missouri in a state where it could be activated again? Did they do that with with any of the other Battleships? Do they just not remove everything from the ship, and dock it and open it to the public in that case?

[Deamon]

I am interested in all eras of submarine history and technological development. Each era has its interesting stories and I enjoy watching the progress of the technology as you move through the years.

I would consider my area of expertise to be the USN submarines, with a focus on the WWII era. I have a good working knowledge of the other country's boats, but I usually defer to other experts once the discussion moves in this direction.
Have you by any chance checked out my articles on my website ?

http://www.dreadnoughtproject.org/heinrich/main.htm

[Kloef]

Pampanito is still partly operational,they take her out for a surface run every 5-7 years according to the site..submerging is out of the question i guess.

Whats very interesting is that she carries the only operational TDC Mark3 in existence,is has been overhauled by a specialist a while ago.

The coding typewriter has been secret untill 1995,and they have one on board in working order,very exceptional since even the museums dont have one..

About 90% of her original missing equipment has been returned and she gets alot of attention,but bringing her back in full operational status is an engineer's nightmare..age really gets to these boats,and she was cannibalized to keep other fleet boats in service for more then 10 years,that really gutted her out bigtime.

i guess it would be cheaper to reverse engineer her and build a new one!

then again you guys keep your history alive,here all boats are sold abroad or stripped and sold as scrap,even the O21 was sold for about 60.000 dollars to a scrapdealer in the 60's..she had great historical value.

We have some boats in the Navy museum in Den Helder,an old Dolfijn class diesel sub that has been put on shore so you can get a real good look at everything,and an old Russian Whiskey class sub in the old part of the harbour but that's it...

[DaveyJ576]

Have you by any chance checked out my articles on my website ?

http://www.dreadnoughtproject.org/heinrich/main.htm

Deamon,

Great stuff. Keep up the good work. I have always had a fascination with Otto Weddigen's U-9. I consider his sinking of the three British cruisers to be a very important event in submarine history.

[Deamon]

Deamon,

Great stuff. Keep up the good work. I have always had a fascination with Otto Weddigen's U-9. I consider his sinking of the three British cruisers to be a very important event in submarine history.

Otto Weddingen, is quite an inspiration. He was the best commander at this time, no doubt. He was also the torpedo referee of the sub fleet. He also managed to keep his crew all the time, which is very rare. He had completely mastered his boat and crew and he was the best damn shooter of the entire german sub fleet( hence he was the torpedo referee ).

Although his performence on the 3 british cruisers was considered a master piece, it is not the first time that he pulled out such stunts. I know of one case during fleet maneuvers in peace time, where he for example shot a 4 torpedo fan ( 2 bow, 2 stern shots ) and scored 3 hits on a battle group.

This is a considerable performence of the entire crew, when you consider the old tech of this early sub design and that the german sub fleet was just a few years old. He was the star of the german submarine fleet.

It is very fortunate for the brits that he died so early into the war. He seemed to had a special luck and skill in comming across british capital ships. I am sure if he would have remained alife he alone would have been a menace for the britsh fleet.

Also it is worth to mention that he died on a new boat(U29). That also came with a new green crew, then he came across 2 other battle goups(of course) and something happened that made the boat broach through the surface during the attack before it got rammed.

A new boat with a new green crew and a formidable tactical challenge was certainly not a fortune combination.

http://www.dreadnoughtproject.org/heinrich/Media/Images/ForumPics/Ktl.%20Otto%20Weddingen%20died%20on%20U29.jpg

A very sympathetic fellow and a real gentleman.

BTW: He also received his basic training on the U 1, the boat that stands in the focus of the simulator I work on.

http://www.dreadnoughtproject.org/heinrich/Media/Images/ForumPics/U_1_at_the_pier.png

http://www.dreadnoughtproject.org/heinrich/Media/Images/ForumPics/Flotilla%205.jpg

http://www.dreadnoughtproject.org/heinrich/Media/Images/ForumPics/Flotilla%207.jpg

[Bubblehead Nuke]

I read that they were keeping the Missouri in a state where it could be activated again? Did they do that with with any of the other Battleships? Do they just not remove everything from the ship, and dock it and open it to the public in that case?

Hello.. I just wandered in from the Dangerous Waters Forum and thought I could share some insight.

When the USN decides to put a ship in long term layup or mothballs, there are some specific things that have to be performed to preserve critical gear. The procedures are extensive and VERY comprehensive.

Obviously the things of main concern are propulsion,damage control, and weapon systems.

For the propulsion train, the screws are removed and the anodes are checked yearly. In the engineroom, all fluids are removed and protective chemicals are applied to prevent corrosion. The spaces are sealed and humidity controls are implemented to prevent a corrorsion friendly enviroment.

For the weapons system, external items are removed if possible to protect them. Every effort is made to protect and preseve the systems so that they can be re-activated. If there are corrosive, explosive, or other potentially dangerous items they are removed and re-located to a protected space.

Damage control wise, you have to make sure that the interior communications system is preseved, the door seals on watertight doors have to be maintained. Some pumps are left available to dewater compartments, others are removed and preservative chemicals applied.

Of course this is a small list of what it done. I have read the navshiptech manuals regarding the procedures and they are mindboggling.

A ship can be placed as a museum and still be able to be re-activated. Most museum ships like to show you 'how they lived'. They do no get into the bowels were the parts that need to be protected are. Sure, you might see a gun turrent, but insurance will prevent you from getting into the engineroom or other large spaces that house the critical gear needed to drive and fight the ship.

[DaveyJ576]

On 14 November 1944, the USS Halibut (SS-232) was on patrol in the Bashi Straight north of Luzon. Around noon that day, her crew picked up an escorted four ship convoy headed northbound. Her skipper, I.J. "Pete" Galantin turned her towards the convoy and engaged. The tactical situation forced a long range torpedo shot and after firing she turned away and submerged. Shortly thereafter a strange buzzing noise (later determined to be Japanese ASW aircraft) was heard followed by five close and devastating depth charge explosions. The boat was badly damaged and Galantin took her to 325 feet seeking safety. Another close, heavy explosion wracked the conning tower and this was followed by two more series of explosions that devastated the control room, the forward battery, and the forward torpedo room. The boat was forced down to 420 feet as the crew fought desperately to save her. At this point the attacks mysteriously ceased and after a point the exhausted crew was able to bring the boat limping to the surface once night fell. The enemy had departed and the Halibut immediately headed to the advance base at Saipan, although without a radio, depth gauges, gyro compasses and suffering from air and water leaks throughout the boat. Temporarily patched up at Saipan, she headed back to Pearl Harbor were it was determined she was beyond economical repair. She returned to the states and was decommissioned at Portsmouth Naval Shipyard on 18 July 1945, never having made another war patrol.

The USS Lancetfish (SS-296) was a Balao class submarine built by Cramp Shipbuilding in Philadelphia. Cramp encountered severe labor and production problems which forced the Navy to tow her to the Boston Navy Yard for completion. After a concerted effort by the workers at BNY, she was commissioned on 12 February 1945, but with many unfinished items still outstanding. On 15 March two yard workmen, arguing about the status of one of the aft torpedo tubes opened it to prove it was dry. Unfortunately, the safety interlocks had been over-ridden and the outer door was open as well. The boat quickly flooded and sank alongside the pier. Raised eight days later from the mud, she was dried out but never repaired. She was decommissioned 24 March 1945, her crew was reassigned, and the boat was sent to the Atlantic Reserve Fleet. She clung to life until 1959 when the Navy finally sold her for scrap. The Lancetfish was never repaired and never went to sea under her own power. She holds the record for the shortest commissioned service of any USN submarine.

Most people may not consider this next one to be a war loss, but the story of the USS O-9 (SS-70) deserves mention. Many of the O-class (that is the letter O, not zero) submarines, built during WWI, had been decommissioned and laid up in reserve as a cost saving measure in the 1930's. Still considered useful, the Navy pulled some of them out of mothballs and recommissioned them as feverish preparations were made to get ready for the war that many believed was coming. The O-9 had laid in reserve for almost 10 years, but despite her poor overall condition was overhauled and recommissioned on 14 April 1941. She was immediately assigned to train crews for the new fleet boats now rolling off the ways. On the morning of 20 June 1941 she got underway from New London for the operating areas off the Isle of Shoals near Portsmouth, New Hampshire. At 0837 she submerged for a dive to test depth and was not heard from again. Two hours later an intensive search was begun, but it was not until evening that debris was finally discovered. The water was 450 feet deep and the O-9 had a nominal test depth of 200 feet. Not much hope held out, but divers were sent down only to discover her shattered remains. The bow was intact but flooded, the rest of the hull aft of the conning tower fairwater had imploded. The crew was dead. The extreme depth proved too hazardous for diving and all rescue and salvage operations ceased on 22 June. Memorial services were conducted and the area designated an official Naval burial ground. In 1997 a survey was made of the site and the following sonar image was recorded:

http://www.navsource.org/archives/08/0807006.jpg

Rest in peace, shipmates.

[DaveyJ576]

The USN submarine skippers of WWII were nothing if not colorful. Many had a great sense of humor and being the inveterate jokesters that they tended to be, a common passtime was labling their buddies with goofy nicknames. Some were descriptive in nature, and some were an expedient to get around long or unpronouncable names. "Red", "Pete", and "Tex" seemed to have been the most popular, each having been used no less than four times each. The following is not a comprehensive list, but contains some of the more entertaining or colorful monikers:

Albert Collins Burrows – “Acey”
James Alvin Adkins – “Caddy”
Raymond Henry Bass – “Benny”
Roy Stanley Benson – “Ensign”
John Herbert Brown – “Babe”
James Harry Campbell – “Soupy”
Wreford Goss Chapple – “Moon”
Bernard Ambrose Clarey – “Chick”
James Wiggins Coe – “Red”
Charles Maynard Cooke – “Savvy”
George Clifford Crawford – “Turkey Neck”
Glynn Robert Donaho – “Donc”
Robert Edson Dornin – “Dusty”
Richard Marvin Farrell – “Dixie”
William Edward Ferrall – “Pete”
Eugene Bennett Fluckey – “Lucky”
Elton Watters Grenfell – “Joe”
William Philip Gruner, Jr. – “Bud”
Frederick Joseph Harlfinger II – “Fritz”
Martin Perry Hottel – “Spike”
Thomas Burton Klakring – “Burt”
Charles Andrews Lockwood, Jr. – “Uncle Charlie”
Vernon Long Lowrance – “Rebel”
Frank Curtis Lynch, Jr. – “Tiny”
Richard Barr Lynch – “Ozzie”
John Sidney McCain, Jr. – “Junior”
Louis Darby McGregor – “Sandy”
Elliott Eugene Marshall – “Steam”
Leonard Sparks Mewhinney – “Tex”
William John Millican – “Moke”
Charles Bowers Momsen – “Swede”
John Raymond Moore – “Dinty”
Dudley Walker Morton – “Mush”
Stuart Shadrick Murray – “Sunshine”
Lawson Peterson Ramage – “Red”
John Paul Roach – “Beetle”
Augustus Robert St. Angelo – “The Saint”
William Bernard Sieglaff – “Barney”
Charles Wilkes Styer – “Gin”
Norvell Gardiner Ward – “Bub”
Frederick Burdette Warder – “Fearless Freddie”
William Leslie Wright – “Bull”
John Herbert Brown – “Babe”
Ignatius Joseph Galantin – “Pete”
Herman Arnold Pieczentkowski – “Pi”
Willis Ashford Lent – “Pilly”
Charles Warren Wilkins – “Weary”


Even though I was just a ordinary enlisted Quartermaster, a Japanese bar girl in Sasebo tagged me with my own nom de plume, for which I became famous throughout the Western Pacific as an international nice guy:

David Lee Johnston - "Skinny Dave"

BTW: This is not descriptive of my current physical state!!
:D

[Kapitan Soniboy]

Hi!

This year it is 100 years since Norway got its first submarine. A US sub (Los Angeles class) and a Russian sub (Kilo class) came to visit us. The US sub was not allowed in to port because it is a nuclear powered submarine so it had to dock a few miles from Bergen at Haakonsvern which is a naval base for Norwegian subs and ships. I talked to one of the Russian officers and he was impressed by my knowledge of his Kilo submarine. (Of course I wouldn't tell him that it was all taken from sub sims:har:) That was very cool but too bad I wasn't able to see the Los Angeles class submarine!

[Sensekhmet]

With all due respect to Norway... I think it's absurd that an official visit is made impossible at the last moment because someone feels nuclear energy is bad. Why did you even let the Kilo in? It's diesel! It pollutes air!
Don't get me wrong, I love Scandinavia: it's a tranquil, beautiful place, the people are nice (at least Swedes... been only to Sweden for now) and it's a real driver's heaven (the roads are fantastic! and there's that small issue of Scandinavia being the world capital of rally and rally cross), but sometimes I just :nope: at such ideas.

[Kapitan Soniboy]

I agree. It's really is absurd that nuclear submarines aren't allowed into our country. BUT it's not up to me.

If you visit Norway you'll find that there's almost no difference between Sweden and Norway.

[Sensekhmet]

I definately plan to. Actually, I'd like to move to Scandinavia and live there. I don't think anything that will happen but we can dream, right?
But give me some time to sort out stuff in my life and I'll probably tour Denmark, Norway, Sweden and Finland in my Volvo 760 turbo diesel I always wanted. Who knows, I might even pick up a Volvo Original Cup car to race back home? :up:

[Kapitan Soniboy]

Sounds nice:yeah:! I know a couple of people from Poland who moved here a few years ago and they are really cool. I've always wanted to ride through Poland, Ukraine and Russia. Don't know why but I am very fascinated by Chernobyl... :oops:

[Rip]

Hi!

This year it is 100 years since Norway got its first submarine. A US sub (Los Angeles class) and a Russian sub (Kilo class) came to visit us. The US sub was not allowed in to port because it is a nuclear powered submarine so it had to dock a few miles from Bergen at Haakonsvern which is a naval base for Norwegian subs and ships. I talked to one of the Russian officers and he was impressed by my knowledge of his Kilo submarine. (Of course I wouldn't tell him that it was all taken from sub sims:har:) That was very cool but too bad I wasn't able to see the Los Angeles class submarine!

I visited aboard the USS Jacksonville (SSN-699) in the eighties. I'll have to dig around to see when it was. One of the better drunken port visits I've had!

[Pacific_Ace]

Great thread idea! :salute:
Im wondering about the effectiveness of ww2 passive sonar vs the speed of the destroyer using it. Currently Im replaying a situation I saved that placed me almost dead ahead of a TF containing 8 AS ships, 3 to a side, one ea front and back, the QE and the Hood :yeah: .
Im inside the screens line of travel waiting for my juicy targets and Im at 1 kt and they are traveling at 19 kts. At this point Im tracking by sonar, yet they still detect me somehow and go active. Im just having a really hard time believing British sonar in late 39 is this good. Any idea whats going on here?

[Stormende]

Hey Davey, I have another question for you. It might seem dumb but remember I am just a virtual sailor so, how was the life inside a sub? With a bunch of people canned inside such a small place, did they get into fights or were strong bonded? Was the odor bad - I know the modern subs have some fancy ventilation system but what about the WWII era ones? Showers, WC? How did the crew ate? I do not think they had a mess room like the nuclear powered ones, right?

Well thankx in advance and keep up the good work!

I love this thread.

:up:

[Pacific_Ace]

Stormende, while I am not Davey and never served in subs, I suggest this link that I found. Lots of stories from people who served in the 'smokeboats'.
http://www.olgoat.com/
You have to click on 'Afterbattery' to get to the stories.

[Stormende]

In the meantime I get the answer from Davey, I will check this site.

Thankx Pacific Ace!

:up:

[DaveyJ576]

Hey Davey, I have another question for you. It might seem dumb but remember I am just a virtual sailor so, how was the life inside a sub? With a bunch of people canned inside such a small place, did they get into fights or were strong bonded? Was the odor bad - I know the modern subs have some fancy ventilation system but what about the WWII era ones? Showers, WC? How did the crew ate? I do not think they had a mess room like the nuclear powered ones, right?

Hey guys!

Sorry about the extended time away. The Navy has kept me busy.

There were several great technical advances for USN submarines in the 1930's, several of which directly contributed to improving the habitability of the boats.

Air conditioning was originally intended for reducing the humidity levels inside the boat and thus greatly reduced the number of condensation induced electrical fires. It had the happy side effect of cooling the air as well. The increased endurance of the crew combined with the reduction of electrical fires enabled the completion of 60+ day patrols in the warm waters of the Pacific Ocean.

Refrigeration allowed the preservation of food for much greater periods of time. It enabled a greater variety and quality of food to be carried, which made the crew happier and healthier, once again increasing their endurance. The scene from Das Boot in which the crew was sitting around the table cutting mold off a chunk of cheese will give you a good indication of what it was like in the days before refrigeration.

Kleinschmidt stills allowed a vastly increased production of fresh water over what was possible from the older evaporators. Better food could be prepared, the crew could stay cleaner, and sanitary conditions increased.

All of these advances greatly improved the quality of life aboard the USN fleet boats. By keeping the crew healthier and happier the boat's ability to carry out its mission improved as well. Other navys often scoffed at these "unneeded luxuries", but the fact remains that the USN was able to work in these new technologies without compromising the fighting ability or mechanical reliability of the boat. If that is the case, then why not do it?

Make no mistake, though, that life on a diesel submarine was some sort of pleasure cruise. It was not.

Even with A/C it was always hot in the boat. It was entirely normal to have interior temps in the 80's F., and temps in the engine room would routinely reach 100 deg and higher. Enginemen would come forward to crew's mess for a drink of water and would start shivering, even though the temp in crew's mess was 85 deg.! The 20 deg difference between the engine room and crew's mess was all it took.

The Kleinschmidt stills were a great advance, but they tended to be a bit cranky. Fresh water production usually fell behind and with most of it going to the batteries and for drinking by the crew, the crew was often restricted in how often you could take a shower. The interval frequently stretched to a week or more. This made for some smelly bodies.

The sanitary tanks that the toilets emptied into were emptied by pressurizing them with air and blowing the contents through a valve and overboard. The crewman conducting this evolution had to follow the procedure to the letter or contents of the tank would force themselves up in a rather forceful manner through sink drains and the toilets and into the interior of the boat. This situation, to put it mildly, is very unpleasant and if it happens makes for a bad day. Even with a successful and proper blowing of the sanitary tanks, before the toilets can be put back into operation, the residual air pressure has to be vented from the tank. If you are on the surface, no problem, it gets vented overboard. But if you are submerged the tank gets vented into the interior of the boat, and this once again is not very pleasant.

Smoke from the engines, incessant noise from ventilation fans and other machinery, zero personal space, and a myriad of unpleasant smells all tended to make life aboard a diesel submarine difficult and trying. Yet despite this, or perhaps because of it, a bond stronger than any other developed amongst the crew. A brotherhood born of shared adversity develops and serious disputes and fights amongst the crew are extraordinarily rare.

I highly encourage you to surf over to the link that Pacific Ace provided above. The stories there by Dex Armstrong give an accurate picture of life aboard a diesel boat. Although written during the Cold War, they still accurately depict the conditions that were faced during WWII. Dex is also an extraordinary writer and his stories are hugely entertaining and sometimes outrageously funny.

[DaveyJ576]

Im wondering about the effectiveness of ww2 passive sonar vs the speed of the destroyer using it. Currently Im replaying a situation I saved that placed me almost dead ahead of a TF containing 8 AS ships, 3 to a side, one ea front and back, the QE and the Hood :yeah: .
Im inside the screens line of travel waiting for my juicy targets and Im at 1 kt and they are traveling at 19 kts. At this point Im tracking by sonar, yet they still detect me somehow and go active. Im just having a really hard time believing British sonar in late 39 is this good. Any idea whats going on here?

The effectiveness of any sonar system, surface ship or submarine, is inversely proportional to the speed of the platform using it. In other words, the faster you go, the worse your passive (listening) sonar gets. There are two main reasons behind this.

As you increase in speed, water flow over the sonar array increases, producing ambient noise. Think of driving in your car, listening to the radio with the window down. If you are at 5 mph the wind noise generated by the car moving is very slight and you can hear the radio with ease. As you increase in speed the wind noise also increases and you are forced to continuously increase the volume of the radio in order to hear it clearly. A similar principle applies to sonar. However, with sonar, at a certain point own ship's speed can render passive sonar completely ineffective (this point varies with the system) and you won't be able to hear a freight train coming at you, much less a quiet submarine.

The other factor is own ship generated noise. As you increase speed, your propulsion plant increases its noise output. The engines, fuel pumps, lube oil pumps, coolant pumps, bearings, reduction gears, and propellers all get noisier as you go faster. This increased noise output from your own ship will make your passive sonar much less effective.

Active (pinging) sonar is much less effected by speed and thus is the type most often used by surface ships while conducting generalized searches. Submarines, however, contrary to what is shown in the movies rarely use active sonar because the ping put into the water will easily reveal it presence to the enemy and allow them to locate you.

I do not have the figures for WWII British sonar systems, but an educated guess would be that at 19 knots a destroyer's passive sonar system would be borderline effective at best. If this is what is happening in the game, it would be my opinion that the destroyer's sonar is modeled incorrectly.

[Fluffysheap]

Another thing to consider is that if there is more than one destroyer, they can cooperate. One can move quietly and listen, and radio bearings to the other one which can move quickly to intercept. I believe this behavior is modeled in both SH3 and SH4.

[donut]

If Mass+Speed= Inertia, shouldn't A sub be able to turn inside A DE of similar length due to slower speed ? Seems not to be modeled in game correctly, the turning radius/speed seems way to tight for DD's ? I do recall man overboard drills, It took almost .5Kn to turn 300Ft DE around at cruise speed to all stop,& lower boat at hard rudder.

[Wilcke]

The stock DD's are agile as cats, turn on a dime and accelerate like drag boats.

jrex53 tackled this issue earlier in the year.

FYI this thread http://forum.kickinbak.com/viewtopic.php?f=11&t=1720

[vickers03]

don't forget the already finished maneuver mod
by webster
http://www.subsim.com/radioroom/downloads.php?do=file&id=942

[Bubblehead1980]

Wouldn't it be great to have a fleetboat that could still safely operate...take a surface run out, dive down to 70 feet or so, then come up...take some tourists on.Kind of like how some B-17's do? When I was a kid(mid 90's) some B-17's came here, charged a somewhat steep fee of course, you get to take a flight inside and it was great.

Of course a submarine is different than airplane but man that would be cool, even just a surface run.

Maybe someone will fork over the money and get one working well enough to do that.

[DaveyJ576]

Wouldn't it be great to have a fleetboat that could still safely operate...take a surface run out, dive down to 70 feet or so, then come up...take some tourists on.Kind of like how some B-17's do? When I was a kid(mid 90's) some B-17's came here, charged a somewhat steep fee of course, you get to take a flight inside and it was great.

Of course a submarine is different than airplane but man that would be cool, even just a surface run.

Maybe someone will fork over the money and get one working well enough to do that.

Bubblehead,

Surf back to posts #287 and 289 in this thread. The long and the short of it is that this is just not going to happen for many reasons. As much as I would love to see one of these boats get underway again (I would be the first one to volunteer for the crew!), there is no feasible or realistic way to make one of these boats safely operational, even if you had the money to do so. It would be better to build a brand new one from scratch. Now there is an idea for you, should you happen to have several hundred million dollars lying around unused! :DL

[H_Nelson]

Hello, I just read to the end this fantastic thread. In few posts earlier I was read about smoking in the navy in past and today. And after I read it, on my mind came how was the relation to the alcohol. Because I remember that in the Royla Navy every member of crew had entitlement on the day ration of rum which issuing was stoped in the 31th July 1970 (if I am right). And my question is follow. Was somthing like in this in the US Navy or it was speciality in Royal Navy? I know that sailor cannot be drunk but was in the duty strict prohibition or was permited to buy some beer in the ship canteen when he was off duty?

P. S.: Excuse me my bad english.

[Nisgeis]

Welcome aboard H Nelson!

[Nuc]

Hello, I just read to the end this fantastic thread. In few posts earlier I was read about smoking in the navy in past and today. And after I read it, on my mind came how was the relation to the alcohol. Because I remember that in the Royla Navy every member of crew had entitlement on the day ration of rum which issuing was stoped in the 31th July 1970 (if I am right). And my question is follow. Was somthing like in this in the US Navy or it was speciality in Royal Navy? I know that sailor cannot be drunk but was in the duty strict prohibition or was permited to buy some beer in the ship canteen when he was off duty?

P. S.: Excuse me my bad english.

See this link: http://www.history.navy.mil/faqs/faq32-1.htm

[DaveyJ576]

Nuc beat me to a reply. I had to work today.

Anyway, it was Secretary Josephus Daniels that outlawed alcohol aboard USN ships in 1914. However, Pharmacists Mates and ship's doctors retained limited stocks of usually brandy or whiskey on board for "medicinal purposes" for many years afterwards. These stocks were strictly controlled by the Medical Department and quite often dispensing them required the Commanding Officer's approval.

Daniel's General Order 99 was issued on 01 Jun 1914, to take effect on 01 July 1914. Reportedly, the mood of the fleet on the evening of 30 June was "festive" as the remaining stocks were rapidly depleted. ;)

I personally think that Sec. Daniels' decision was the right one. It was an important step in the transformation of the USN into world class, professional navy. Not that a navy that allows rationed alcohol consumption on board (like the RAN) is unprofessional, it is just that the decision was the right one for the USN at the time and it reflected a cultural trend of that era.

Much has been said over the years about the military-civilian cultural "gap" that often keeps the military lagging behind the rest of the civilian world when it comes to dealing with cultural issues. There is a gap of sorts, but only because the Navy and the rest of our armed forces are forced to approach certain social issues from a different perspective. This different approach is required due to the very nature of what the armed forces does and how its' members have to be motivated and led. This gap, however, is not as large as some people would have you believe and the prohibition order of 1914 reflected this. Temperence and abstaining from alcohol consumption was a fairly strong conservative trend in our society at the time and Sec. Daniels was an adherent of this philosophy. The mere fact that he was able to issue this order without a major upheaval is evidence that he had a reasonably high level of support.

While the banning of alcohol aboard ships certainly contributed to a more professional atmosphere, the consumption of booze while ashore on liberty continued. Over the years, the popular image of the drunken sailor was continuously reinforced by sailors blowing off steam after a long run at sea. This popular passtime for shore side sailors was often easily tolerated by their command and as long as the sailor returned the the ship on time and could do their jobs once they arrived, the Navy would usually look the other way. Submariners in particular became legendary in this regard and their parties became the stuff of legends.

As we moved into the 1990's, the attitude of the USN underwent a dramatic change. American society in general became less and less tolerant of drunken behavior and alcohol related incidents and penalties and fines increased accordingly. The USN's policies mirrored that of greater society and Navy Regs began to reflect this. The USN also became very concerned over the impacts that alcohol related incidents were having in fleet wide efficiency (i.e. loss of man hours in dealing with the incident and the post incident aftermath), the loss of highly trained sailors to alcohol related deaths, and the negative publicity shined on the Navy by these incidents. It is now to the point that any sort of alcohol related incident will most likely be a career killer.

While I agree that a certain amount of boozing while ashore might be considered traditional for a sailor, I can't help but heartily agree with the policies of de-glamorizing alcohol use and the stiff penalties for its' abuse. Losing sailors to alcohol abuse is just plain stupid and the future of the Navy is at least partially dependent on maintaining a squared away and professional image in the minds of the public.

[Rockin Robbins]

We "moderns" do not appreciate the culture of drunkenness that was a prevalent part of society up through about the 1950s. The stereotype of the hard drinking detective or newspaper man is based on a truth of the time. We do much today to fight drunk drivers and the like, but in those days the drunk was a respected member of society. The newspaper I work for still has payday on Wednesday because in the 1930s and 1940s Friday payday resulted in half the workforce too hung over on the weekend (the most important newspapers) to get the work done!

The drunk was deemed not responsible for his actions and in "Andy Griffith" type paternalism, was allowed to sleep it off in jail overnight and released without incident. The drunk sports reporter was the epitome of manhood. The "hard drinking man" was almost a hero. Even preachers were known to be drunks without impacting their status. The American military could not afford to be complacent about such an accepted lifestyle, especially in view of the profane, freewheeling, Dex-like character of its typical crew members. They lived to party, and there was a legitimate place for that. But it was not while on duty.

Given American culture of the time the military made the exactly correct decision. From our perspective in time it's almost impossible to understand the extreme difference in culture between them and us.

[Bert68]

My first boat was the USS Blackfin SS322 out of Pearl. I picked it up in Nov 1954 and we left on a 6 month WestPac trip on Jan 3rd 1955. I did go thru sub school in New London, Conn and made a couple day cruises while in school but once you are stationed on a sub life changes a bit. Half of our crew were old WW2 sailors and some went thru some bad depth charges also. I went into the engineroom gang as they were short handed for firemen at the time. Never was sorry for this choice as I learned a lot while I moved up thru the ranks and got qualified in submarines.

One thing I hated was the damn diesel smell as it got buried into your body, cloths and always stunk. I think I had a headache from the fumes for 7 years along with the popping of the snorkle valve opening and closing. In fact I was talking with my Captain from 1955 to 1957 era and he said the snorkle done a number on his sinuses also.

Talking of booze on board ship. Hmmm. We never lacked for a drink by any means. If we knew we were going on a 30 day patrol we would stock up the lockers and had our ration daily for sure. On one occasion we made a 90 day patrol in 1959 off of Russia we loaded so much beer into the ventilation system to keep it cold it almost shut off the air to the manuvering room. Now one of the electricians knew we put the beer in there but we agreed to give him one now and then and not tell the others. As we had a good refer system installed on board in 57 it would really pump out the cold air but since the line was almost plugged in there the other electricians were always gripping how hot it was and the line wasn't working right. At the time I was an auxilaryman and they would call me up and I would say "I will look into it." Course the more beer we drank out of there the more air got into the compartment so they thought I was a wizard fixing it for them. Hehehehe...

I got to say some people had no business being sub sailors at all and should have never qualified and most of these were wardroom attendents. One night out on patrol this fellow from the wardroom had to come back and blow the crap tank in the afterbattery compartment. There were two deck drains that had to be closed and the inboard vent. The discharge valve was in the forward engine room on the stbd. side. Well he closed the valve and deck drains put some pressure in the tank then opened the overboard discharge and dumped the tank, 1100 gallons, opened the vent valve and deck drains and forgot to close the overboard valve. I was sleeping in a lower bunk about 10" off of the deck and had heard him do all of this but he left and for some reason my right arm flopped out of the bunk right into about 6" of water. I knew right away what happened so passed the word we were flooding and then jumped into the engine room and closed the valve but we were worried about getting salt water into the battery well so all lights came on and we grabbed all of the pots and pans out of the galley and was throwing the water into the engineroom. What a mess that was but luckly nothing happened.

I guess I could ramble on about other things that happened along the way but got to say we had some sharp guys on board and we all pulled together to make one hell of a working team for the Captain and the other officers. If I recall correctly we won 3 engineering E's right in a row and proudly had them painted on the sail too.
Bert

[DaveyJ576]

Much has been said about the relatively low rate of losses for the USN Submarine Service in WWII when compared to other navies. The most common explanation given for this situation is the comparatively inept and lackluster ASW efforts on behalf of the IJN. While this is certainly true, one other factor must be considered. The USN fleet boats were extraordinarily tough and resistant to fatal damage. When you threw in the never-say-die attitude of the well trained and experienced crews, the IJN either had to get in a very lucky shot, or wound up having to pound the living crap out of these boats to get them to sink.

Why was this? Manufacturing facilities in the United States were very modern in the 1940's. The latest technologies and techniques were being employed (such as welding) and this allowed a break with the processes of the past. Having just pulled themselves out of the Great Depression, the workers employed at these plants were very motivated to put out a quality product (they wanted to make sure they kept their jobs!). Management practices were also the best in the world, keeping the workers happy and productive and the plants humming a peak efficiency.

The result was a high quality product. The fleet boats were some of the most technologically advanced and refined submarines of the era. Production quality was very high from all facilities (Cramp Shipbuilding being the sole exception) and lessons learned and new technologies were incorporated fairly rapidly. Electric Boat did tend to drag their feet when it came to working in new gear to the boats, but pressure from the operating forces and the Navy made them see the light. Build quality, however, was never in question.

Today I was doing some web surfing and came across some war damage reports that highlight the toughness of the fleet boats. It is very interesting reading. There are some great photos and very informative color plates. Some of the passages in these reports give me the shivers because I know what conditions inside these boats must have been like.

Report of the USS Kingfish (SS-234) damage from depth charges off Formosa, 23 March 1943. This attack damage was one of the prime factors leading to the deletion of the access hatch in the aft bulkhead of the conning tower. http://www.ibiblio.org/hyperwar/USN/rep/WDR/WDR58/WDR58-5.html

Report of the USS Tunny (SS-282) damage from depth charges off Palau, 26 August 1943. http://www.ibiblio.org/hyperwar/USN/rep/WDR/WDR58/WDR58-6.html

Report of the USS Scamp (SS-277) damage from aerial depth charge off Mindanao, 7 April 1944. I quote the following from the report because it is extraordinary: "The deformation which occurred to both the inner and outer hull structures as a result of this attack is the most severe known to have been survived by any U.S. submarine during World War II."
http://www.ibiblio.org/hyperwar/USN/rep/WDR/WDR58/WDR58-9.html

The next one is the report of the damages sustained by the USS Salmon (SS-192) from depth charges on 30 October 1944. This is one of the most incredible stories of survival that I have ever read.
http://www.ibiblio.org/hyperwar/USN/rep/WDR/WDR58/WDR58-7.html

In all of these cases the superb construction quality of the boats and the nearly superhuman efforts of the crew brought the boats home. If the IJN had been slightly more persistant, we could very well have lost four more boats.

Now, for an example of what it really takes to sink a fleet boat, take a look at this report. It concerns the USS Tang (SS-306) and her loss to a circular run of a Mk 18-1 torpedo. The fact that anyone survived the catastrophic damage she endured is testament to the well trained and disciplined crew.
http://www.ibiblio.org/hyperwar/USN/rep/WDR/WDR58/WDR58-10.html

[Sailor Steve]

If Mass+Speed= Inertia, shouldn't A sub be able to turn inside A DE of similar length due to slower speed ? Seems not to be modeled in game correctly, the turning radius/speed seems way to tight for DD's ? I do recall man overboard drills, It took almost .5Kn to turn 300Ft DE around at cruise speed to all stop,& lower boat at hard rudder.
I'm sorry I wasn't around when this was posted, because I've done a lot of research on how ships turn, and the surprise is that unlike cars and planes, a ship doesn't go fast enough to force a wider turn radius, and since at 40 knots or less the action on the rudder is dependent on the speed, the faster a ship goes the tighter it turns.

Specific numbers I have include the trials of the battleship HMS Dreadnought. At 12 knots it took her more than a minute to turn her first 45 degrees, while at 21 knots it took 40 seconds. After that she accelerated into the turn and was turning about 135 degrees per minute at 21 knots. Of course a ship that size creates a lot of drag, and she lost about 3 knots per minute doing that.

Most destroyers' listed tactical diameters give their best turning at around 20 knots, but you can bet a DD at 12 knots is indeed going to outturn a submarine going 8. And lose a lot less speed doing it.

[Sensekhmet]

So can a ship/boat actually turn 'too fast'? And what would the consequences be?
I know what happens to cars and bikes (I'm an amateur racer and a certified motorsport marshal), I can even imagine what happens to tracked vehicles but imagination fails me when 'floaters' are concerned.
For a few years now my town hosts one of the inshore European speedboat championship races*. Everytime I'm surprised to see those boats not slowing at all for a tight switchback around a buoy and still make the turn. I see it but I don't understand it. The only problem these guys seem to have is hitting the wake of a competitor and nosing down into the water. That stops them pretty damn fast.

* Here's a picture of one of the fastest classes, O-700 I think:
http://upload.wikimedia.org/wikipedia/commons/8/8f/%C5%9Arem_motorowodne_Attila_Havas.jpg

[Sailor Steve]

If by "too fast" you mean fast enough to lose control, then no. They use what is called a "discplacement hull", which means they sit in the water, and when they turn they tend to heel outward. This can seem to be fairly extreme, but under normal circumstances they just can't go fast enough to get into trouble.

http://i14.photobucket.com/albums/a325/SailorSteve/6148.jpg


And:
http://www.youtube.com/watch?v=_Encki1BzXo
http://www.youtube.com/watch?v=0NbIOM7U8xc&feature=related

A boat on the other hand uses a "planing hull", which sits on top of the water. This lets them achieve much higher speeds, and when they turn they lean into the turn. This includes PT boats, which in WW2 weight upwards of 50 tons. They also weren't fast enough to lose their grip, but a high-speed racing boat certainly can. In even a slight chop one of those is sometimes bouncing completely out of the water, and in a turn can do exactly what a car does - get just a little too tight into the turn, lose its grip and flip right over. And over, and over, and over.

[Sensekhmet]

Thanks for clearing this up. And yeah, those speedboats usually (as in: straight line with throttle fully open) contact the water just by their propellers/rudders. I've noticed some lower class speedboats with v-shaped bottoms sometimes hop excessively even on a relatively clam lake, with some taking a list on wither left or right side with every hop. Looks dangerous, possibly some ballast problem?

[LukeFF]

Dave: was there any standard as to how many 3" and 4" deck gun rounds were carried on average during a patrol? I have read the wartime standard for the 5"/25 was 75 rounds, but finding an answer for the other two calibers still eludes me.

[DaveyJ576]

Dave: was there any standard as to how many 3" and 4" deck gun rounds were carried on average during a patrol? I have read the wartime standard for the 5"/25 was 75 rounds, but finding an answer for the other two calibers still eludes me.

Luke,

Great question! This will take some digging. None of my otherwise informative and reliable references give a number. However, in the meantime lets assume that for stability reasons the amount of ammo carried is fixed by weight. The 5"/25 round weighed 75 lbs each. 75 of these shells come out to 5625 lbs. The 4"/50 round weighed 65 lbs and the 3"/50 round 25 lbs. Doing the math this comes out at 86 rounds for the 4"/50 and 225 rounds of 3"/50. These numbers are probably not overly accurate, but it gives us something to start with.

I will let you know what I come up with.

[LukeFF]

Thanks, Dave. :)

I've another question for you (and I think this one is a bit easier ;)): how many men at a time would stand watch in each diesel compartment?

[CameramanDavid]

just curious as to why the designers put them in the game when they didn't exist until 1958... Chief was the top of the the enlisted structure until then...

David
Los Angeles
Nuc Waste 1984-1987
Subase Pearl Harbor Radcon

[DaveyJ576]

Thanks, Dave. :)

I've another question for you (and I think this one is a bit easier ;)): how many men at a time would stand watch in each diesel compartment?

Check out post 183 in this thread. :)

[DaveyJ576]

just curious as to why the designers put them in the game when they didn't exist until 1958... Chief was the top of the the enlisted structure until then...

I can't really answer that, it is obviously a mistake on the programmers part. However, I am actually impressed with all the things they got right, especially in some of the exterior details on the boats. Not perfect, but pretty darn good. :up:

[LukeFF]

Check out post 183 in this thread. :)

Aha! Yes, now I remember that question came up before. :D

[LukeFF]

Dave,

In response to your post above:

Without having the manual in front of me, I would say that the typical fleet boat engine room would probably have a 1st Class Motor Machinist Mate in charge in the room, along with two to three assistants, 2nd class and below. This would be duplicated for the other engine room, with one Chief Petty Officer in charge of both rooms. This arrangement would be duplicated again for the other watch sections, which there was usually three.

The control room would typically have a Motor Mac at the air manifold, one at the trim and drain manifold and 1 to 2 Quartermasters at the chart table for navigation (in the Navy a Quartermaster is a navigator, not a supply clerk). Once the boat submerged, the lookouts would come below and man the diving planes (these could be any rate, it didn't matter), and a Chief or officer would become the Diving Officer, supervising the planesmen.In looking through many fleet submarine crew rosters it, seems that the typical number of machinists/firemen per sub was 21-22. Now, here's my dilemma: looking at the initial roster for a boat sailing in June 1944 (USS Icefish), the following machinists/firemen are listed:


2 Chief Motor Macs
4 First Class Motor Macs
5 Second Class Motor Macs
3 Third Class Motor Macs
7 Firemen First Class

(Interestingly, there was not a Third Class rate for machinists until 1944; until then, that billet was filled by Firemen 1st Class).

That's a total of 21 altogether. Now, assuming a total of 6 men will be on duty in the control room, that leaves 15 men for the diesels. Assuming, then, that 5 men at a time will be detailed for a diesel compartment watch, it would seem to me that one senior petty officer plus an assistant would be on watch in each compartment. Hence, that would leave 3 men to be in charge of both compartments per shift. Put another way:

Air Manifold: 3 men
Trim/Drain Manifold: 3 men
Fore Diesel Compartment: 6 men
Aft Diesel Compartment: 6 men
Senior Diesel Petty Officers: 3 men

That's about the only way I can figure that's how the watches worked. However, there's also this line from the Fleet Sub Manual on diving operations:

If everything is in order in the engine rooms-oilers to control room-for submerged stations.If that means that there were, say, only 1 man regularly on watch at the air manifold, then each diesel watch could have 1 senior petty officer plus 2 assistants. Or, am I reading this wrong? Were both manifolds manned at all times?

Hopefully I've not muddied the waters here too much. :D

[DaveyJ576]

Luke,

Great info and some good detective work!

Here are some inputs:

Firemen are considered to be "non-rated", i.e. they do not have a specific job classification and can be assigned to any of the engineering divisions. Some of the Firemen listed may have been assigned to the Electrical Division (E-Div), some to Main Propulsion (M-Div), and some to Auxiliaries Division (A-Div). Those assigned to E-Div would have stood watch in the Maneuvering Room at the cubicle and would have been busy taking gravity readings in the battery well, lining up for battery charges, etc. Being non-rated, it also would not have been uncommon to see a Fireman standing watch in the control room at the dive planes, helm, and lookouts or even loaned out to the torpedo rooms or gun teams as hired muscle.

The air manifold and trim & drain manifold would only have had one sailor standing watch each and these men would have been assigned to A-Div.

Once the war started, rigid adherence to the peacetime manning and organizational documents kind of went by the wayside. We had manpower to spare and the boat CO's were given a fairly high degree of latitude to organize their watch sections as they saw fit. As long as the CO could demonstrate that he could effectively and safely fight his ship, he could pretty much do as he pleased when it came to organization.

Given the rapid pace of the war and the excess of manpower, it was extraordinarily difficult for the Bureau of Personnel to precisely adhere to the manning documents and regulate what rates and how many of each rate were assigned to each boat. This would account for the variations that you are seeing in the crew rosters.

You are making an admirable and concerted effort to ensure that your RFB crew rosters are as accurate as possible. I applaud your efforts. Unfortunately, given what I said above, I think you may want to generalize, have it make sense, and move on.

Thanks for your hard work on the mods!:yeah:

[LukeFF]

Dave,

You're absolutely right. I've had to make a few concessions to the crew lineups, based on what the SH4 engine allows. One of the biggest of these is the fact that the maneuvering and diesel compartments are not separate, so I've had to lump together all the machinists and electricians together into one compartment with one rating. I would love to have more fidelity with how the ratings and compartments are divided up, but it just can't be done.

A couple more questions for you:


Who else besides radiomen would be trained to operate the radar equipment?
What types of duties did Signalmen have on submarines?

[DaveyJ576]

A couple more questions for you:


Who else besides radiomen would be trained to operate the radar equipment?
What types of duties did Signalmen have on submarines?


The rate of Radarman (RD or sometimes RdM) was established in 1942. This would have been the primary source for radar operators. However, in a situation similar to sonar operators, because this was fairly new technology and few people had proper training in it most captains would send just about anyone in the crew who showed an aptitude for electronics to radar school. Along with the Radiomen, it would not have been uncommon to see Yeoman, Ship's Cooks, Quartermasters, or non-rated Seamen operating the radar. Once sufficient numbers of RD's starting showing up, they would have taken over this duty.

Like their surface ship brethren, Signalmen (SM) on submarines would have been responsible for all non-radio based communications, i.e. semaphore, blinker light, and signal flags. However, since submarines operated mostly independently and submerged a lot of the time, SM's had precious little rate specific jobs to do. Their normal underway watch station probably would have been helm/planes/lookout and would have been additionally tagged for gun and ammo handling details and may have helped the Torpedomen in handling and loading torpedoes.

[DaveyJ576]

As far as the gun ammo loadout issue, I have been completely stymied in finding this information. None of my normal contacts can provide a number. Probably the reason behind this was that it varied so much from patrol to patrol and from boat to boat. As the war progressed, many additional ammo storage tubs were added topside to hold ready service ammo. The numbers and sizes of these tubs were limited only by the creativity of the boat crews and the yard workers installing them, with stability concerns factored in. This situation alone would have greatly varied the ammo loadout. In addition, the configuration of the ammo magazine under crew's mess was probably tinkered with often by the yard crews in an attempt to pack in as much ammo as stability would allow.

With all this in mind, there probably isn't a "typical" amount of ammo carried. To get what the as-designed loadout was, you would probably have to refer to the original design prints stored in the National Archives.

However, for game programming purposes the numbers that I cited above would be a good starting point. An educated guess would be that 225 rounds of 3"/50 is probably on the high side. 175 would be a more reasonable number. The numbers for 4"/50 and 5"/25 are probably pretty close.

[LukeFF]

The rate of Radarman (RD or sometimes RdM) was established in 1942. This would have been the primary source for radar operators. However, in a situation similar to sonar operators, because this was fairly new technology and few people had proper training in it most captains would send just about anyone in the crew who showed an aptitude for electronics to radar school. Along with the Radiomen, it would not have been uncommon to see Yeoman, Ship's Cooks, Quartermasters, or non-rated Seamen operating the radar. Once sufficient numbers of RD's starting showing up, they would have taken over this duty.

That's about what I thought and along the lines of what I've read. The only thing is that, as far as my research goes, it was very rare to see the Radarman rate on board a submarine (I think I've seen only one or two examples of a boat with a Radarman-rated petty officer). More commonly, it seems, a single petty officer with the rate of Radio Technician would be included among the sub's complement, and he would be the one in charge of radar equipment.

Like their surface ship brethren, Signalmen (SM) on submarines would have been responsible for all non-radio based communications, i.e. semaphore, blinker light, and signal flags. However, since submarines operated mostly independently and submerged a lot of the time, SM's had precious little rate specific jobs to do. Their normal underway watch station probably would have been helm/planes/lookout and would have been additionally tagged for gun and ammo handling details and may have helped the Torpedomen in handling and loading torpedoes.

In other words, "all other jobs as required." :D

[LukeFF]

With all this in mind, there probably isn't a "typical" amount of ammo carried. To get what the as-designed loadout was, you would probably have to refer to the original design prints stored in the National Archives.

However, for game programming purposes the numbers that I cited above would be a good starting point. An educated guess would be that 225 rounds of 3"/50 is probably on the high side. 175 would be a more reasonable number. The numbers for 4"/50 and 5"/25 are probably pretty close.

That's probably about right. I've done some calculations from patrol reports that detail the amount of ammo expended, and those numbers seem about right, though like you mention, the numbers can and do vary greatly from boat to boat.

Interestingly, for comparison, is the amount of German 105mm rounds stored in a Type IX U-boat. A post-war study found that the boat was designed to hold 250(!) rounds. I would be curious to find an example of a fleet sub that carried a comparable amount of 4" ammo. That seems like an awful lot of large-caliber ammo for one boat to carry.

[LukeFF]

Dave,

What types of parameters were used to record how fast a boat could dive? That is, I'm looking for the following info:


Speed at start of dive
Depth at which dive time stops

The only hint I have at this point is that, in the ONI manual on U-boats, the dive times are listed as "Crash Diving Time to Periscope Depth."

[DaveyJ576]

What types of parameters were used to record how fast a boat could dive? That is, I'm looking for the following info:


Speed at start of dive
Depth at which dive time stops


Diving times were usually measured under the following parameters: boat fully surfaced and running at a standard bell (approx. 15 knots), and time to get to periscope depth. For the Gato/Balao/Tench classes PD was 65 feet. At the start of the war the fleet boats were credited with 50 second dive times. By the end of the war that was down to an average of 40 seconds. With a lot of training some boats were able to dive in 30 seconds. For a boat the size of the fleet boats this was pretty impressive.

[LukeFF]

Diving times were usually measured under the following parameters: boat fully surfaced and running at a standard bell (approx. 15 knots), and time to get to periscope depth. For the Gato/Balao/Tench classes PD was 65 feet. At the start of the war the fleet boats were credited with 50 second dive times. By the end of the war that was down to an average of 40 seconds. With a lot of training some boats were able to dive in 30 seconds. For a boat the size of the fleet boats this was pretty impressive.

Thanks as always, Dave! This info here made me realize how off I was on the dive times for RFB.

[LukeFF]

Dave,

Do you have any data handy on surfaced acceleration rates for fleet subs? I have good data on submerged acceleration rates but none for the other.

[DaveyJ576]

Dave,

Do you have any data handy on surfaced acceleration rates for fleet subs? I have good data on submerged acceleration rates but none for the other.

I am expecting a package from a friend out in California that will have construction data in it on the Gato class boats. When I get it I will take a look. Other than that, nope. I am sure those data curve charts exist (or existed) somewhere, but I haven't seen them.

[Nit]

Dave, please publish this data at a forum. It would be desirable to know the data of dive time exactly.

[Fishbreath]

Reading patrol logs from www.hnsa.org (http://www.hsna.org) I see a lot of skippers writing things like "proceeded at three-engine speed".

Now, I assume this means that they have one engine shut off for fuel reasons (?), but how hard are they driving the other three, and about how fast would they be going?

[LukeFF]

Dave,

In other recent conversations here, it's been discussed where the ladder in the Gato/Balao control room was actually located during the war years. Pics such as this one from Wahoo show it to be behind the dive planes:

http://www.navsource.org/archives/08/0823825.jpg

While this undated picture shows it to be behind the main gyro compass:

http://img.photobucket.com/albums/v258/LukeFF/FleetSubControlRoom.jpg

So, was it standard during the war to have the ladder behind the dive planes? And if so, was it part of the postwar revision process to move the ladder to the other position? Pampanito shows the ladder to be behind the dive planes. Since it doesn't seem like that particular boat was extensively modified in the postwar years, that would lead me to believe the ladder's correct position should be behind the dive planes.

[DaveyJ576]

Reading patrol logs from www.hnsa.org (http://www.hsna.org) I see a lot of skippers writing things like "proceeded at three-engine speed".

Now, I assume this means that they have one engine shut off for fuel reasons (?), but how hard are they driving the other three, and about how fast would they be going?

A USN fleet submarine has four "normal" ahead speed settings: 1/3, 2/3, standard, and full. A 1/3 bell would have one engine/generator on line and would provide a max of about 6-7 knots (a knot is one nautical mile per hour, a nautical mile is exactly 2000 yards). A 2/3 bell would have two engines on line and would give you about 8-11 knots. Ahead standard would have three engines on line and would provide about 11-15 knots. Finally, ahead full has all four engine/generator sets on line and and will give you about 15-18 knots. In most cases, the engine is set to run at it's most fuel efficient speed. You vary the boat's speed within the ranges that I gave by varying the amount of electricity that is sent to the motors, sending the rest to the batteries as a "running charge".

While charging batteries, you will normally have multiple engines on line, but your speed will be reduced because much of the current is being drawn off for the battery charge. For instance, if your battery is badly depleted, you can have a four engine battery charge running but your speed may only be about 8 knots. As the battery charges up, less and less current is sent to the batteries so the excess is drawn off to propulsion and the boat's speed gradually increases.

Now you are probably wondering about the ahead flank bell. Flank speed is a special condition that is achieved by running all four engines at their maximum rated speed and lining the batteries up in series and pulling extra current out to supplement what is coming from the engine/generators. This condition will push the boat to it's maximum rated speed of 21 knots. This obviously will draw down the battery charge.

When the Barb made her famous raid into Namkwan Harbor, Gene Fluckey had his engine room chief tie down the governors on all four of the GM 16-248's and ran up a 150 percent overload. In this condition, Barb was estimated to have hit about 25 knots while exiting the harbor. This is a very dangerous condition and once clear of the harbor they "slowed" to flank speed to keep the engines from tearing themselves apart and to allow the shaft bearings to cool!

Notice how many times above that I said "about" when refering to speed. The maximum achieveable speed is dependent upon the material and mechanical condition of the propulsion plant and the amount of marine growth on the hull. Thus, it is not uncommon to have a submarine whose max speed is reduced by several knots. A thorough overhaul and hull cleaning would correct this, but you didn't get those very often.

[DaveyJ576]

The location of the conning tower ladder did vary a little bit from one boat to another. However, it never moved very far.

It is important to remember that no two boats came out of the builder's yard exactly the same. There were always numerous minor detail differences from one boat to the next. One of these minor variances could have been the location of this ladder. The general location was fixed by two features that did not vary: the location of the conning tower in relation to the control room, and the location of the conning tower hatch which was always in the forward port corner of the conning tower. Therefore, the ladder leading up to it from the control room was always going to be in the general vicinity of the dive planes and gyroscope.

I think the variation that Luke is seeing is simply a 90 degree rotation aft. Some boats that I have seen has the ladder rungs facing the dive planes. Others have had the ladder rungs perpendicular to the planes. I think what they were doing was rotating the ladder 90 degrees aft along the conning tower hatch rim. This would have gotten it out of the way of the planesmen. This was probably a later mod that was based on operational experience.

One other factor that might be affecting what you are seeing in the photos is the location of the trim and drain manifold in relation to the air manifolds. The fleet boat control room had a "dry" side and a "wet" side. The air manifold for blowing ballast tanks was always on the opposite side of the control room from the trim manifold used to vary the amount of water in the trim tanks. This was usually an Electric Boat vs. Government yard difference; one used a dry port/wet starboard config and the other a wet port/dry starboard config. Which was which is escaping me right now (old age brain fart!!). This difference may have moved the location of the dive planes station a little forward or aft and this may be accounting for some of the differences you are seeing.

[Sailor Steve]

(a knot is one nautical mile per hour, a nautical mile is exactly 2000 yards).
Actually a nautical mile is exactly:

One minute of arc along a meridian of Earth

1852 meters

2,025.372 yards

6,076.1155 feet

As established by the First International Extraordinary Hydrographic Conference, held in Monaco in 1929.

The United States didn't adopt this standard until 1954, but even during the Second World War it wasn't exactly 2000 yards - it was 6080.2 feet, which is 2026.7333 yards.

[DaveyJ576]

Actually a nautical mile is exactly:

One minute of arc along a meridian of Earth

1852 meters

2,025.372 yards

6,076.1155 feet

As established by the First International Extraordinary Hydrographic Conference, held in Monaco in 1929.

The United States didn't adopt this standard until 1954, but even during the Second World War it wasn't exactly 2000 yards - it was 6080.2 feet, which is 2026.7333 yards.

I stand corrected! :salute: I always strive for accuracy and this one eluded me completely! During my days as a U.S. Navy Quartermaster, we always used 2000 yards as our baseline for navigational computations and never ran into problems. Interesting.

[LukeFF]

I think what they were doing was rotating the ladder 90 degrees aft along the conning tower hatch rim. This would have gotten it out of the way of the planesmen. This was probably a later mod that was based on operational experience.

That was my guess as well. Based on all the interior photos I've seen, the above-posted photo with the ladder perpendicular to the planes was probably either taken late in the war with, say, a Tench class boat or a photo taken in the immediate postwar era.

[Fishbreath]

<snip informative post>

Thanks a lot. I wasn't entirely clear on the relationship between ordered bell and which engines are doing what, and now it all make sense.

[Platapus]

Flank speed is a special condition that is achieved by running all four engines at their maximum rated speed and lining the batteries up in series and pulling extra current out to supplement what is coming from the engine/generators. This condition will push the boat to it's maximum rated speed of 21 knots. This obviously will draw down the battery charge.




I learn something every time I read this thread. :yeah: I never knew that flank speed drained the batteries. I just thought flank speed was overreving the motors.

[Nuc]

That was my guess as well. Based on all the interior photos I've seen, the above-posted photo with the ladder perpendicular to the planes was probably either taken late in the war with, say, a Tench class boat or a photo taken in the immediate postwar era.

These builder's plans for a Balo class show the ladder behind the planes station

http://thumbnails19.imagebam.com/6818/8a92d868173335.gif (http://www.imagebam.com/image/8a92d868173335)

Edit: In Looking at the plans and the pictures of the ladder I noticed that in the game the hatch is rotated 90 degrees from where it should be. regardless of the ladder orientation the long axis of the hatch runs fore and aft with the hinge such that the open hatch is up against the port side of the conning tower. In the game it runs the other way (athwart ship) and when opened the hatch would stick up in the middle of the deck.

[LukeFF]

Dave:

In this overhaul picture of the Wahoo, taken in July 1943, I have a couple of questions about some of the objects on the bridge:

http://www.navsource.org/archives/08/0823843.jpg

-The circular item on the far left: is that a voice tube?
-Is the item adjacent to the above item a pelorus?
-The "box" on the far right: is that a loudspeaker?

[SSGSlick]

USS Cod ..thought you guys might appreciate ...

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD829.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD838-1.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD647.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD794.jpg


http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD641.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD653.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD617.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD581.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/100_3517.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD815.jpg

[Andrew82]

Wow, great pictures thanks for posting! :yeah: :salute:

[RodBorza]

Davey,
I got a question about battery recharge.

In the SHIII stock game, it seems that for the U-Boats too recharge their batteries they had to disconnect an engine from the propeller, and connect it to a generator and do the recharge. It reflects on the boat's speed and engine rpms.

But Fleet boats as it seems had 4(!) Diesel engines. And when recharging, the speed is not affected at all. So, how was the operation to recharge? Two engines to propell the boat and the other two disconected from the propeller shafts and connected to generators to recharge? And after that, all four would be connected to the propeller shafts (two engines starboard, two port)?

And what is the size of those diesel engines? 12 cylinders? 24 cylinders? I never visited a boat museum but I just wonder what the size of the machine room mighty be. It must be enormous (for a sub, that is)!

I have this questions and I got say that I really liked post #116 (on the batteries) because as an electrical engineer these matters are really interesting to me.

Tks! Great thread!

[magic452]

SSGSlick :yeah::yeah::up: 5 thumbs up.
Those are some outstanding pics, both in content and quality.

Thanks for posting.
Magic

[LukeFF]

But Fleet boats as it seems had 4(!) Diesel engines. And when recharging, the speed is not affected at all. So, how was the operation to recharge? Two engines to propell the boat and the other two disconected from the propeller shafts and connected to generators to recharge? And after that, all four would be connected to the propeller shafts (two engines starboard, two port)?

And what is the size of those diesel engines? 12 cylinders? 24 cylinders? I never visited a boat museum but I just wonder what the size of the machine room mighty be. It must be enormous (for a sub, that is)!

Until Dave can give a more detailed reply, this page (http://www.hnsa.org/doc/fleetsub/diesel/chap1.htm#1D) from the Fleet Submarine Manual describes the size of the diesel engines and a general description of how they recharged the boat's batteries.

[RodBorza]

@LukeFF

Thanks man! Very nice site.
The page you lead me to contained much more information that I could think of.
That picture showing a sub cutaway with all of its engines is, for me, very clarifying.

Very good! :up:

[RodBorza]

SSGSlick

Thanks for the pics!
They are very nice.

They sure give the dimension of the sheer size of the engines room.
No wonder Fleet Boast were much larger than U-Boats.

And 4 V16 Engines? That's a lot of horsepower.

[RodBorza]

Bear with me, but since I never even got near a real sub, I have this very mundane questions that are boggin me for a while .

1) Bathrooms:
Yeah, you read it right: bathrooms ;). I saw a documentary on modern nuclear subs and it said that there are only one or two for the entire crew (expect captains have their own) and baths are a luxury. Although modern subs crew is shown most of time with their uniforms nice and clean, the pictures from WWII show exactly the opposite. So I imagine that laundry too was out of question and maybe today it still is.
(in a way, a sub is a single man's way of life dream come true...:D)


2) Sleep: I read some posts ago that the shifts were 4 on - 8 off. But even so, sleep was a very rare commodity: why is that? From the sim, it takes long and boring hours to get to the area of operations and looking out for convoys. Not to mention that during the day some skippers maintained the sub submerged to avoid air patrols.
From what I know, modern subs crews spend most of the time studying and training, because promotions and graduatios take part while the boat is underway. And what about during the WWII and Cold War?

3) Potable water: again, modern subs use sea water, dessanilize it and use it to give current water. Or am i wrong? And how it was on WWII?

4) CO2 scrubbers: in the WWII they weren't used on subs. But after it? In the 50's and 60's? Did they suffer with the same issue of acumulating CO2?

Well that's it.

Thanks for your patience.

P.S.: As a side note, it can be noted that sub naval warfare may have contributed to the U.S. space program in more ways than not. I wonder if it is why NASA would prefer armed forces officers for their crews.

[SSGSlick]

4 × General Motors Model 16-248 V16 diesel engines (total of 5400 brake horsepower) driving electrical generators capable of 4 Megawatts

2 × 126-cell Sargo batteries

4 × high-speed General Electric electric motors with reduction gears

Each of those 4 diesels weigh in at over 42 thousand pounds ..21 tons each!

During her seven combat patrols those beasts drank more than a million gallons of diesel!

These babies actually still run !

There's actually a fifth engine, buit it runs the house and is not tied to the propulsion or charging system ...

The guys that maintain her acquired 2 additional engines form the Stingray (SS186) and will use to refurb and maintain the Cod's powerplant ... there's no batteries on board, just ballast to make up for the weight.

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD803.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD813.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD683.jpg

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/USSCOD686.jpg


About 40 more pics from last spring ... http://s705.photobucket.com/albums/ww56/SSGSlick/cod/

Cod is the only remaining fleet sub that hasn't had her pressure hull breached to install stairs or ramps for visitors, in theory she could still submerge if you could crew her,that and you couldn't get much of the boat underwater as Erie is way too shallow, in most places the sail would be fully out of the water ..

If you're ever within visiting distance, the Cod is worth the trip .. the last time I was aboard it was like a Wednesday afternoon and there was nobody else there .. it was pretty cool being the only parson aboard .. one of the guys that still volunteers on the boat was on her when she rescued the grounded Dutch submarine O-19 .. he's interesting to talk to as he had been underway on her, although not on combat patrol.

Enjoy ..
TC

[DaveyJ576]

Dave:

In this overhaul picture of the Wahoo, taken in July 1943, I have a couple of questions about some of the objects on the bridge:

http://www.navsource.org/archives/08/0823843.jpg

-The circular item on the far left: is that a voice tube?
-Is the item adjacent to the above item a pelorus?
-The "box" on the far right: is that a loudspeaker?

Wow! Take a couple of days off and see what happens! Lots of great posts!

Anyway, Luke you are very nearly correct.

The object on the left is a voice tube. It would normally have been used to communicate rudder and speed orders to the helmsman that was stationed at the surface steering station on the navigation bridge, immediately below the main bridge. The problem here is that the surface steering station, along with the entire covered nav bridge has already been removed in this photo! This was part of the effort to reduce the boats' silhouette. The tube would not have been used to speak to the helmsman inside the conning tower or control room because the tube would have to penetrate the pressure hull and thus would have to be watertight and pressure proof. This tube is obviously not closed or sealed so the only thing I can think of is that it is a leftover from the original installation, were it would have been completely outside of the pressure hull.

The item in the center is actually an early model Target Bearing Transmitter (TBT)! This was used in conjunction with a set of standard 7x50 binoculars that were attached to the mount on the top. The binoculars were unclipped and taken below before you dived.

I am not entirely sure, but I believe the object on the far right is an early model "squawkbox", a combination microphone and speaker used to communicate orders to the conning tower and control room. It was pressure proof and was usually activated by pushing down a switch on the side. I have not seen one of this style before. Later models were much smaller and round.

[DaveyJ576]

Davey,
I got a question about battery recharge.

In the SHIII stock game, it seems that for the U-Boats too recharge their batteries they had to disconnect an engine from the propeller, and connect it to a generator and do the recharge. It reflects on the boat's speed and engine rpms.

But Fleet boats as it seems had 4(!) Diesel engines. And when recharging, the speed is not affected at all. So, how was the operation to recharge? Two engines to propell the boat and the other two disconected from the propeller shafts and connected to generators to recharge? And after that, all four would be connected to the propeller shafts (two engines starboard, two port)?

The U-boats used a propulsion method called Direct Drive. The crankshaft of the engine was clutched to a motor/generator, which in turn was clutched to the propeller shaft. Normal surface operations had the engine directly turning the propeller with both clutches engaged. When you dived, you shut down the engine and de-clutched it from the motor, which drove the boat with electricity from the batteries. To charge the batteries you would surface, start the engine, de-clutch the motor from the shaft and engage the clutch between the engine and the motor. With the engine turning the motor it now generated electricity which was used to charge the battery. This arrangement had obvious negative implications for surfaced speed.

The USN fleet boats (with a few minor exceptions) used Electric Drive. That is, the engines were not connected to the propeller shaft in any way. They only drove generators. Electricity created by the gens would be sent to the motors attached to the shaft. Alternately, you could charge the battery by using a portion of the generated electricity to charge the battery (see the 2nd paragraph of post #352). Once again, anytime you charged batteries, it had a negative impact on speed. This is indeed modeled incorrectly in the game. The RFB mod may have corrected this. LukeFF??

Interestingly, the USN experimented with tandem drive engines in the early 1920's in the G and T class boats. They took two engines and connected them together at the crank shaft, sometimes with a clutch and sometimes without. This was a well intentioned attempt to greatly increase shaft horsepower, but it was a complete failure. The mechanical/manual control systems of the time were unable to precisely match the speeds between the two engines. Even a small mis-match would result in bad, sometimes violent vibrations that would break crankshafts and engine mounts and eventually destroy the engines.


EDIT: check out this link: http://www.fleetsubmarine.com/propulsion.html It gives a pretty good overview of submarine propulsion.

[DaveyJ576]

Bear with me, but since I never even got near a real sub, I have this very mundane questions that are boggin me for a while .

1) Bathrooms:
Yeah, you read it right: bathrooms ;). I saw a documentary on modern nuclear subs and it said that there are only one or two for the entire crew (expect captains have their own) and baths are a luxury. Although modern subs crew is shown most of time with their uniforms nice and clean, the pictures from WWII show exactly the opposite. So I imagine that laundry too was out of question and maybe today it still is.
(in a way, a sub is a single man's way of life dream come true...:D)

Hi Rod!

I will tackle this in a series of posts.

USN fleet boats had four toilets (properly called heads) in the boat. The first one was in the forward torpedo room and was intended for use by the officers (but was routinely used by the enlisted as well). Two more were placed side by side in separate stalls on the starboard side just aft of crew's berthing. The fourth was usually in the aft port corner of the maneuvering room. These toilets were situated directly above a tank called a sanitary tank. After making your "deposit" you flushed the bowl by pushing down on a lever on your right. This opened a ball valve in the bottom of the bowl that allowed the contents to fall into the sanitary tank. You would then open up a valve and flush a little sea water through the bowl. Next, shut the ball valve and allow the bowl to partially refill before shutting the flushing valve.

Obviously, sooner or later the sanitary tank fills up. To empty it you start off by securing the toilet (why will be explained shortly), then you go around and shut a valve on every drain line that empties into the tank. Once this is done, air is bled into the tank, pressurizing it (the amount of pressure varies depending on how deep you are). Once pressurized, you open a valve at the bottom of the tank and the contents are blown over the side in a nasty liquified brown ooze. When empty, you close the overboard valve and carefully vent off the pressure from the tank. If you are surfaced the pressure would obviously get vented to the outside. However, if submerged you have no place to go with the pressure except inside the boat. This has a very nasty impact on the air you are breathing, to put it mildly. After venting all the pressure off the tank you open all the drain valves and put the heads back in service. Voila!

Now here is were it gets interesting! Several problems can potentially arise during this procedure. First, flushing water is sea water that comes obviously from outside. It will be under the same pressure as what the outside is. When on the surface, the valve opens easily and the water runs into the bowl in a nice leasurely stream, no problem. Once submerged the back pressure on the valve makes it increasingly harder to open. Just cracking it open at 150 feet and the water rushes into the bowl in a mad torrent. At test depth you run the very real possibility of flooding the boat if you are not extremely careful.

Secondly, during the blowing procedure you have pressurized the tank with air. If someone enters the head and uses the toilet during this time, as soon as he opens the ball valve under the bowl the contents of the tank will follow the path of least resistance and come up through the ball valve and into the head! Imagine a Mt. Vesuvius of crap! The unfortunate sailor who made this mistake will exit the head covered head to toe with liquified human excrement. Words can not describe how incredibly nasty this is. Also, if you fail to fully close every drain valve, the contents will force their way up the drain lines and into every sink they service. Do this in the captain's cabin and you will have a very bad day! :D

The Kleinschmidt stills onboard the fleet boats were a tremendous advance over the earlier evaporators. When new and properly serviced they actually produced an excess of fresh water. This allowed for normal use of fresh water for cooking, cleaning, washing, showering, and the batteries. This was a tremendous technological advance for our boats and was one of the prime factors that made 60-80 day patrols in the warm Pacific doable and tolerable for the crews. There was even a washing machine in the crew's head in the after battery! This was completely unheard of in other country's boats.

However, the Kleinschmidt stills were notoriously cranky and often times did not produce as much water as was wanted. The majority of this had to go to the batteries so the first thing that got cut out was showers and the washing machine. Even still, the relative abundance of fresh water was a real morale booster for the crew and went a long way to keep them healthy and ready to fight.

[DaveyJ576]

Bear with me, but since I never even got near a real sub, I have this very mundane questions that are boggin me for a while .

2) Sleep: I read some posts ago that the shifts were 4 on - 8 off. But even so, sleep was a very rare commodity: why is that? From the sim, it takes long and boring hours to get to the area of operations and looking out for convoys. Not to mention that during the day some skippers maintained the sub submerged to avoid air patrols.
From what I know, modern subs crews spend most of the time studying and training, because promotions and graduatios take part while the boat is underway. And what about during the WWII and Cold War?

Well you basically answered your own question. There was a lot more going on underway than watchstanding and sleeping. Most captains drilled the crew relentlessly while enroute to patrol station. This honed their skills and kept them ready to face the enemy. The non-qualified personnel had to study to learn the boat in order to earn the Silver Dolphins of a qualified submariner. There were daily field days (all hands cleaning sessions) and routine scheduled maintenance to perform. Many of these things had to be completed while the sailor was off watch, which ate into their sleep time. Once on station, battle stations could be called at any time. All and all a submarine on patrol was a busy place indeed and sleep was truly at a premium.

3) Potable water: again, modern subs use sea water, dessanilize it and use it to give current water. Or am i wrong? And how it was on WWII?

I answered this in the post above!

4) CO2 scrubbers: in the WWII they weren't used on subs. But after it? In the 50's and 60's? Did they suffer with the same issue of acumulating CO2?

The fleet boats did not have active CO2 scrubbers and oxygen generators like the modern nuclear boats do. However, all boats carried multitudes of canisters of lithium hydroxide. This powdery substance is an awesome CO2 absorber. Literally all you needed to do was open the can. It worked best though when you spread it out on the deck or preferably on a mattress.

There was no way at the time of replenishing oxygen once it had been used up. You could bleed some air into the boat from the air banks, but the quality of this air was not the greatest and you needed it to get to the surface. It also increased the pressure in the boat and this had a negative effect on the crew. The only practical way of replenishing the air was to surface, open the hatches and main induction, light off an engine and draw fresh air into the boat.

P.S.: As a side note, it can be noted that sub naval warfare may have contributed to the U.S. space program in more ways than not. I wonder if it is why NASA would prefer armed forces officers for their crews.

Strangely, despite being uniquely suited to being cooped up in a tube for long periods of time and being very competent with complicated mechanical and electrical systems, NASA has roundly ignored submarine sailors for the astronaut program. Until recently that is. In July, 2000 NASA selected Captain Stephen Bowen, USN for its program. Captain Bowen is Qualified in Submarines and served onboard the USS Parche (SSN-683), Pogy (SSN-647), Augusta (SSN-710), and Virginia (SSN-774). He flew as a mission specialist on flight STS-126 to the ISS. He performed three spacewalks during the mission.

[RodBorza]

Davey,

You are the greatest!

Thank you very much for your answers.

Amazing. Just amazed me.

I thought my questions were too mundane to be answered. But seeing that a simple thing as going to the bathroom, in a sub, can get very complicated surprised me.

Now I can see why the crew didn't get to sleep much, because a "simple" thing as cleaning a sanitary tank could take a lot of operations that needed to be learned and trained well.

About the potable water, another interesting answer. Never thought of having water could be a morale booster. I think in situations like these you give thanks for the simplest of the things.

Regarding the engines and motors, it is nice to know that in a sub you have a very similar operation to what is done in locomotives. Very interesting to see the difference of philosofies of propulsion systems between Americans and Germans. It seems to me that the American system is more reliable, less prone to breakdowns and would allow for a multitude of alternatives in case an engine was damaged or offline for maintenance.

Also, I read post #352 on the motors and recharging the batteries. It is a shame that the game does not simulated this condition, of having the boats speed coming up as the batteries got recharged. Then, that button to turn-off recharge would be useful (mods anyoone?).

And finally, I got say that I apreciatted that you took your time to even answer the side note about NASA that i put there. It is interesting to know that Cernan, Lovell, Schirra and Shepard were all naval aviators, but sadly, no submariner, until the distinctive gentlemen you mentioned there.

Yet again, thanks!

Good to have you around!

P.S.: From the link you game me:
"Some indication of the amount of power consumed by these motors was the necessity to include water cooling systems to keep the operating temperatures within safe limits. The high speed type motors (used with a reduction gear) were rated at 1370 horsepower and ran at 1300 rpm, pulling 2600 amps at 415 volts. (By way of comparison, an automobile starter motor runs on 12 volts at a maximum draw of around 45 amps.)"

I got say, as an electrical engineer, that is, really a lot!

[SSGSlick]

Officer's head ..

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/offhead.jpg

Christmas tree ....

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/tree.jpg

Conning Tower ...

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/contwr.jpg

Looking forward to bow .. standing on pressure hull below deck .. I wonder if the three CO2 tanks correspond to 3 starboard fwd tubes ?

http://i705.photobucket.com/albums/ww56/SSGSlick/cod/bow.jpg

[RodBorza]

Great pictures!!!

It gives an good idea of which is which in the game.

[LukeFF]

Once again, anytime you charged batteries, it had a negative impact on speed. This is indeed modeled incorrectly in the game. The RFB mod may have corrected this. LukeFF??

It's not really anything I can correct, sadly. It seems the game runs the diesels at max RPM while the batteries are charging, thus affecting only fuel consumption.

How was battery charging typically handled on USN fleet subs? If the boat was cruising (i.e., not needing to run at high speeds) were, say, a pair of diesels used to charge the batteries while the other pair were used to propel the sub? From the link I posted (http://www.hnsa.org/doc/fleetsub/diesel/chap1.htm#1D), it also says the auxiliary engine could also be used to charge the batteries.

[DaveyJ576]

How was battery charging typically handled on USN fleet subs? If the boat was cruising (i.e., not needing to run at high speeds) were, say, a pair of diesels used to charge the batteries while the other pair were used to propel the sub? From the link I posted (http://www.hnsa.org/doc/fleetsub/diesel/chap1.htm#1D), it also says the auxiliary engine could also be used to charge the batteries.

It really depended on the circumstances. There wasn't a typical setup. It really was driven by the state of the battery.

Lets say it is early in the war and you are transiting to your patrol area. Doctrine at that time called for submerged transits during the day and surfaced at night. After being down all day the battery was pretty well drained. After surfacing you would come up on all four engines and start a full load battery charge. Your diesels would be pounding away like rock crushers, but you may only be making about 6 knots in speed. As the battery charged up (this would take several hours in this case) more and more current can be drawn off for propulsion and your speed increases gradually.

Now lets say that just as dawn breaks you encounter a convoy of three ships escorted by a couple of cans. You make an end around, submerge, and knock off a couple of maru's. The cans are moderately competent and keep you down for an hour or two. Afterwards, you pop up and set off in a chase for the last ship. You started off with a full battery and now might be down to a half charge. You would probably come up on all four engines again, but proceed at three engine speed and put the fourth on the charge. You would have to balance tactical considerations (i.e. the need for speed) against the practical need to charge a partially depleted battery.

Later in the war as doctrine evolved, boats were making most of the transit to station on the surface. Your battery never really gets drawn down, but there is always a slight drain on it. Once arriving on station you could goof around waiting for a contact on two engines (speed not really a factor here) and keep a "running charge" going in order to keep the battery charged up.

Now lets say you needed the speed but still needed to do a partial charge. You could put all four engines on line, but charge the battery using the auxiliary engine (sometimes called the "dinky"). The dinky doesnt produce a lot of power, but it is sufficient for a slow speed transit or a slow charge.

See what I am getting at? There were many different combinations of propulsion vs. charging and how you did it would be entirely dependent on the circumstances at the time.

[sergei]

Just want to say this is my favorite thread on subsim.
Always something interesting to read here. Very informative and interesting.
Thanks for taking the time to do this DaveyJ576 :up:

[lynx]

It would want to make the following question: If as a result of the combat some battery were broken and the electrolytes would be mixed with salt water and would take place feared; gas of cloro; , that system of gas extraction used? or if so how they avoided the gas?
Thanks

[LukeFF]

See what I am getting at? There were many different combinations of propulsion vs. charging and how you did it would be entirely dependent on the circumstances at the time.

Absolutely. It's one of those things I wish we had more control over in the game.

[LukeFF]

Dave,

How did the promotion system work for USN enlisted men during the war? In the U-boat force, if a junior enlisted sailor was selected for NCO school, he was required to leave his current boat and attend NCO training. Upon the completion of this he would be assigned to a new boat. Was a similar system in effect with the USN? In addition, what was the procedure for 1st Class petty officers promoting to CPO?

[Deamon]

I would have a question about electric engines. Right now i try to implement the electric plant in my sim but i have a hard time to figure out how i have to used the e-engines to charge the batteries. How do i turn the e-engine from a current consumer to a current producer ?

Is there any special wiring required to turn the e-engine into a generator or something ?

[DaveyJ576]

It would want to make the following question: If as a result of the combat some battery were broken and the electrolytes would be mixed with salt water and would take place feared; gas of cloro; , that system of gas extraction used? or if so how they avoided the gas?
Thanks

Chlorine gas is extremely toxic and deadly. Only a small amount is necessary to kill. If you are submerged and this happens, you have no way of getting rid of the gas. You would have to evacuate the battery compartment and seal it off. If you had to be exposed you could use a gas mask. The normal procedure would be to surface as soon as possible and ventilate the boat in the normal fashion. Obviously if the enemy is lurking about, this would have to wait.

In the USN fleet boats, the individual battery cell "jars" were made out of two layers of hard rubber, with a very thin impermeable rubber membrane between the layers. This design allowed the jar to flex during depth charge attack without cracking. If it did, the membrane would contain the acid inside. This was a key technological advance and was an important factor in the high survival rate of the USN boats.

[DaveyJ576]

I would have a question about electric engines. Right now i try to implement the electric plant in my sim but i have a hard time to figure out how i have to used the e-engines to charge the batteries. How do i turn the e-engine from a current consumer to a current producer ?

Is there any special wiring required to turn the e-engine into a generator or something ?

I know that there are differences in languages, but in the USN "electric engines" are usually refered to as "motors", with the term "engines" being used to refer to the diesels.

Anyway, first I have to state that I am not an electrician so please forgive if I goof on electrical theory. As I understand it, any motor can also be a generator. In direct drive submarines (like most of the U-boats) if the diesel was clutched into the motor and turning, it would produce electricity acting as a generator. If the diesel was de-clutched and current from the battery was being applied to the motor, it acted as a motor and turned the shaft. No changes in wiring were needed. All it took was the proper alignment of the clutches and the battery breakers. It is actually simpler than what you might think!

[RodBorza]

I know that there are differences in languages, but in the USN "electric engines" are usually refered to as "motors", with the term "engines" being used to refer to the diesels.


Davey is right. It is a confusion outside the English language.
For instance, in Portuguse the word "motor" can designate both type of engines (mechanical) and electrical (motors). In German, I think, the same applies.


Anyway, first I have to state that I am not an electrician so please forgive if I goof on electrical theory. As I understand it, any motor can also be a generator. In direct drive submarines (like most of the U-boats) if the diesel was clutched into the motor and turning, it would produce electricity acting as a generator. If the diesel was de-clutched and current from the battery was being applied to the motor, it acted as a motor and turned the shaft. No changes in wiring were needed. All it took was the proper alignment of the clutches and the battery breakers. It is actually simpler than what you might think!


Davey,
USS Plunger skipper and resident electrical engineer here:salute:. I believe I can lend you a hand.

Not all electrical motors can be generators. Only DC motors can do that. (some AC can, but with modern technology). I believe that at that time there were only the brushed DC electrical motor type available. The beauty here is that if you turn them, you get electricty out of it. If you apply electricity, they turn. As simple as that.

So, Deamon, take a look at Post # 371. There Davey gives a very nice explanation how it worked on the German and US subs.

Regarding the German type, as the engine was turning and the gen/motor was connected to it, they could recharge the batteries while propelling the boat. There would be no need to disconnect the motor from the propeller to do a recharge as modeled in the game. They could do that at any speed. Well, in theory.

I believe that in the game it is disconnected because when they do it the engine is accelerated to flank speed while recharging the batteries. I don't know if in SH4 you can see it, but in SHIII you can see this difference very clearly in the command room on the engines telegraph above your Diving Officer. While the port engine is at the speed you set, the starboard is set at Flank, recharging.
I think the fact why they do that is because DC generators work better at a determined speed (they generate more electricity with less mechanical force).

And to answer your question, no, you don't need any special rewiring of the circuits. As said above, if you turn the gen/motors they will give you electricity. If you apply electricty, they will turn. All that you would need (without all the protections and alternative schemes) was an On-Off switch.

P.S.: Oh yeah...There's a very important feature that I forgot to talk about. In DC gen/motors you need to have at least a residual battery power left to energize the field coils. Field coils work as permanent magnets around the main or rotor coil. You take electricity out of rotor coils, but NEED to have the field coils energized otherwise the gen won't work.
If the event that you got 0% of battery power, you would be unable to recharge, because there would not be electricity to power the field coils, thus not enough power to excite the rotor coils, thus no generating, thus no recharging... In other words: you would be dead in the water.

[Deamon]

As I understand it, any motor can also be a generator. In direct drive submarines (like most of the U-boats) if the diesel was clutched into the motor and turning, it would produce electricity acting as a generator. If the diesel was de-clutched and current from the battery was being applied to the motor, it acted as a motor and turned the shaft. No changes in wiring were needed. All it took was the proper alignment of the clutches and the battery breakers. It is actually simpler than what you might think!
Dave thanks, however i know that laready but i ren into some problems during implementation and i need to know more.

[Deamon]

Not all electrical motors can be generators. Only DC motors can do that. (some AC can, but with modern technology). I believe that at that time there were only the brushed DC electrical motor type available. The beauty here is that if you turn them, you get electricty out of it. If you apply electricity, they turn. As simple as that.
Yes it were shunt wound motors. I am new to electrical engineering so i have a bit of a hard time to figure out how exactly that works.

So, Deamon, take a look at Post # 371. There Davey give a very nice explanation how it worked on the german and US subs.I know that already but i still have some open questions.

Regarding the German type, as the engine was turning and the gen/motor was connected to it, they could recharge the batteries while propelling the boat. There would be no need to disconnect the motor from the propeller to do a recharge as modeled in the game. They could do that at any speed. Well, in theory.But i presume that during charging the e-motors would produce resistence equivalent to the same current during discharge ?

I believe that in the game it is disconnected because when they do it the engine is accelerated to flank speed while recharging the batteries. I don't know if in SH4 you can see it, but in SHIII you can see this difference very clearly in the command room on the engines telegraph above your Diving Officer. While the port engine is at the speed you set, the starboard is set at Flank, recharging.
I don't play this games anymore :)

I think the fact why they do that is because DC generators work better at a determined speed (they generate more electricity with less mechanical force). And to answer your question, no, you don't need any special rewiring of the circuits. As said above, if you turn the gen/motors they will give you electricity. If you apply electricty, they will turn. All that you would need (without all the protections and alternative schemes) was an On-Off switch.On-Off switch, what exactly does this switch turns on/off ? You mean the conncetion of the motor to the battery ?

Correct me if i am wrong but in my understanding the e-motor generates electricity already when it is driven by the batteries, is that correct ? This way it also acts as a natural governor.

So if you want to charge the batteries you need to run the e-motor with the diesel faster than the e-motors top rpm during discharge, otherwise you cannot overpower the battery and reverse the current flow(hense the diesel has to run flank). Is that correct ?

[RodBorza]

On-Off switch, what exactly does this switch turns on/off ? You mean the conncetion of the motor to the battery ?

Yes, just that. All you need is a switch between the e-motors and the batteries. When you want to recharge, close the switch. Electricity flows from the generators to the batteries.
Open it after recharge.
When submerged, you need to close that switch again to allow power from the batteries to flow to the e-motors.


Correct me if i am wrong but in my understanding the e-motor generates electricity already when it is driven by the batteries, is that correct ? This way it also acts as a natural governor.

Yes, you are right, but you are getting into a detail that is intrinsic to the DC generator.
For practical reasons, when driven by the batteries, it only consumes battery power and don't send any energy back to the batteries. The energy "generated" inside the rotor is very small and only causes the effect of governing the speed.


So if you want to charge the batteries you need to run the e-motor with the diesel faster than the e-motors top rpm during discharge, otherwise you cannot overpower the battery and reverse the current flow(hense the diesel has to run flank). Is that correct ?
No, I don't think so.

In the U-Boats the motor top speed is the same of the diesel engine. So RPM in diesel and in electrical should be the same. So, you can run the e-motors at Flank speed no problem (with, of course, the batteries getting depleted at a very fast rate). The fact that you recharge at flank speed is because at that speed you can have the highest power output (best V, best A) from the generator and will be able to recharge the batteries faster.

If I understood this right, you want to now if overcharging the batteries and then feeding the e-motors with the overload can cause a higher rpm, thus a higher speed. Well, yes it will. Can be used for emergency situations, but the life of the motors will be reduced somehow. Not to mention the danger of doing it, since switching DC is far moe dangerous than switching AC.

[Deamon]

The energy "generated" inside the rotor is very small and only causes the effect of governing the speed.
Are you sure it is only small ? in my understanding it should actually become even higher than what is drawn from the batteries cause this is the only way how you can send current from the motor to the batteries. You have to reverse the potential, means produce a higher voltage with the motor than what the battery currently have.

If I understood this right, you want to now if overcharging the batteries and then feeding the e-motors with the overload can cause a higher rpm, thus a higher speed. Well, yes it will. Can be used for emergency situations, but the life of the motors will be reduced somehow. Not to mention the danger of doing it, since switching DC is far moe dangerous than switching AC.No that is not what i wanted to know. I am talking about how does the current batteries voltage gets topped by the motor, i mean how does the current gets reversed and flow from the motor to the batteries ?

Again, in my current understanding to achieve this you need to generate more voltage with the motor than what is in the batteries(overpowering). But you said the motors generate only little voltage so how do you top the battery voltage ?

[RodBorza]

Are you sure it is only small ? in my understanding it should actually become even higher than what is drawn from the batteries cause this is the only way how you can send current from the motor to the batteries. You have to reverse the potential, means produce a higher voltage with the motor than what the battery currently have.

No that is not what i wanted to know. I am talking about how does the current batteries voltage gets topped by the motor, i mean how does the current gets reversed and flow from the motor to the batteries ?

Again, in my current understanding to achieve this you need to generate more voltage with the motor than what is in the batteries(overpowering). But you said the motors generate only little voltage so how do you top the battery voltage ?

Ok, there's a miscommunication here. So, what you want to know is even simpler: the current flow occurs naturally from the point with the higher voltage (source) to the point with the lower voltage (load).

Now I understand what you meant.

Let's say you have 90% battery charge and put the generator to recharge. So, in this case you need to put the gen at flank speed because it will generate more voltage (100% V) than what the batteries have, so current will flow from the gen to the batteries. It goes until the batteries are at 100% V, then the current flow would get to zero and there's nothing else you should do.

In other scenario, if you have the batteries at 10% V and the generator set at ahead standard (let's say 50% V power being generated) you would recharge the batteries up to 50% V. In order to recharge the other 50%, you would need to set the generator at a higher speed (more V).

That's is the reason why they put the generator at Flank speed. It will generate at the highest voltage available and send it to the batteries. Depending on the state of the batteries, if the charge is very low, more current will flow from the generator to the batteries and it will get lower as the battery voltage increases.

Then it is a matter of opening a switch, enganging the clutch again and that's it. Batteries charged, propulsion normal.


When feeding the motors with the batteries, things are even simpler.
Once you submerge, the engine is disengaged from the motor by the clutch, then you close the switch and the current will naturally flow from the batteries to the motor, since the batteries will be at higher voltage than the motors. In this case, for the source (batteries) the load (motor) will always be at a lower voltage. No need for a special operation of any kind, since it occurs naturally.

[Deamon]

Ok, there's a miscommunication here. So, what you want to know is even simpler: the current flow occurs naturally from the point with the higher voltage (source) to the point with the lower voltage (load).

Now I understand what you meant.

Let's say you have 90% battery charge and put the generator to recharge. So, in this case you need to put the gen at flank speed because it will generate more voltage (100% V) than what the batteries have, so current will flow from the gen to the batteries. It goes until the batteries are at 100% V, then the current flow would get to zero and there's nothing else you should do.

In other scenario, if you have the batteries at 10% V and the generator set at ahead standard (let's say 50% V power being generated) you would recharge the batteries up to 50% V. In order to recharge the other 50%, you would need to set the generator at a higher speed (more V).

That's is the reason why they put the generator at Flank speed. It will generate at the highest voltage available and send it to the batteries. Depending on the state of the batteries, if the charge is very low, more current will flow from the generator to the batteries and it will get lower as the battery voltage increases.

Then it is a matter of opening a switch, enganging the clutch again and that's it. Batteries charged, propulsion normal.


When feeding the motors with the batteries, things are even simpler.
Once you submerge, the engine is disengaged from the motor by the clutch, then you close the switch and the current will naturally flow from the batteries to the motor, since the batteries will be at higher voltage than the motors. In this case, for the source (batteries) the load (motor) will always be at a lower voltage. No need for a special operation of any kind, since it occurs naturally.
RodBorza, thanks. However this much i already figured out. What i wasn't sure about though was how much voltage does a particular motor generates at a given RPM ?

I wasn't sure what a realistic approximation would be, cause it seems to me that the motor, even at top speed, would run on a fairly low voltage, compared to what the battery provides. Would you agree on this ?

Another thing i need to figure out is what is the maxim current that we can take out of a battery ? Or in other terms what is the internal resistance of a typical u-boat battery cell ? and what can the typical resistance of the power lines from the batteries to the motors be ? Lets say we have a battery of a nominal voltage of 130.

What i also need to know how much amps do we loose through the resistance ? Particularly when we run the current through serie resistors for regulation purposes.

Also can i load the batteries with any power level or is there a limit how much the batteries can take ?

[RodBorza]

Daemon,

Try these links:

http://www.uboat.net/articles/id/54 (http://www.uboat.net/articles/id/54)

http://www.uboat.net/technical/batteries.htm (http://www.uboat.net/technical/batteries.htm)

http://sourceforge.net/apps/trac/derleitendeing/wiki/VIIbatteries (http://sourceforge.net/apps/trac/derleitendeing/wiki/VIIbatteries)

http://sourceforge.net/apps/trac/derleitendeing/wiki/MainPropulsionEngines (http://sourceforge.net/apps/trac/derleitendeing/wiki/MainPropulsionEngines)

These gives you a very good information source to start. But I believe that for the kind of info that you are looking for, the best course of action is to try to contact the original manufacturers. They are still around (although with different names). Since you are in Germany, I believe it would be easier for you to ask them what you need.

[kraznyi_oktjabr]

Hello gentlemen!

I just started playing in Balao boat in 1944 and I got question about radar use.

How US boats used their radar? Did they keep it on all times or did they do just occasional sweeps?


At my understanding todays radars' problem is that they often tell more about yourself (radar type, bearing etc.) to enemy than you find out yourself. Is that correct and if so what was situation during WWII? Did fleet boats have any radar warning equipment? Capability to identify radar types?

Thanks!

Tim

[DaveyJ576]

How US boats used their radar? Did they keep it on all times or did they do just occasional sweeps?

At my understanding todays radars' problem is that they often tell more about yourself (radar type, bearing etc.) to enemy than you find out yourself. Is that correct and if so what was situation during WWII? Did fleet boats have any radar warning equipment? Capability to identify radar types?

Despite the fact that the USN only employed it's first primitive radar set in 1939, American scientists (using in part technology borrowed from the British) made rapid advances in radar development during the war. By the end of the war, radar technology had advanced to the point that nearly every USN platform, including some aircraft and even PT boats carried relatively powerful and capable radar sets. When combined with the Plan Position Indicator (PPI) scope, which gave an overhead "birdseye" view of the battlespace, radar proved to be an absolutely key factor in the defeat of the Japanese. The importance of this technology to the U.S. war effort can not be overstated.

Japanese developments in this regard were far behind the U.S. Japanese warships did not begin to see radar sets until almost halfway through the war. Even then they were primitive when compared to the USN sets, were unreliable, and were very scarce. It was very hit or miss when it came to which ships received the few sets available.

Accordingly, radar detection and classification technology was non-existent on the IJN side and only in it's most primitive state in the USN. There was no ability classify and/or jam radars as there is today. Therefore, USN submarines could use their radars with virtual impunity. It would be a stretch to say that they left it on all the time, but nearly so.

However, as the USN operators got more and more experience with their new gear they found that it had an unintended capability. In February, 1945 the USS Batfish (SS-310) detected strange intermittent interference patterns on their SJ radar set. When an IJN submarine showed up a short time later, the crew of the Batfish concluded that it was radar sweeps from the submarine. They promptly dispatched the RO boat, and two others that were detected in the same fashion over the next three days.

[DaveyJ576]

As some of you have already noticed, the awesome website Navsource Naval History (www.navsource.org (http://www.navsource.org)) has published a series of articles called "A Visual Guide to U.S. Submarines". The index page with the articles can be accessed through this link:

http://www.navsource.org/archives/08/10idx.htm

(Insert shameless self-promotional plug here! :DL)

I have been busy over the last several weeks. I have been working on the articles for the last several years, with early versions of the S-boat articles originally published on the site that my website partner and I founded a few years ago: www.pigboats.com (http://www.pigboats.com). I have spent the last several weeks reformatting the articles and converting them to .pdf format. Deciding to try to expand the exposure of the articles, Michael Mohl, the webmaster of the Navsource submarine pages, graciously agreed to post them on his pages. I have also been working with Neal Stevens and eventually they may be posted here as well.

The intent of the articles was to provide the casual reader a better understanding of how to visually identify the various classes of USN submarines of the WWII era. You would really be amazed at how many photos I have found over the years, some in respected publications, that are misidentified. The fleet boats are all similar enough in appearance that it is easy to make a mistake. But when the photos are carefully studied, definite patterns emerge. The articles were a result of what I found from looking at literally hundreds and hundreds of photographs.

The photographic record is maddingly incomplete and as I come across new ones I try to refine the articles. If new info turns up I will update the articles accordingly. I am working on follow on articles for the Salmon/Sargo class and eventually the Porpoise/Shark/Permit, Balao, and Tench classes.

This is a rather arcane subject so if after reading the articles any questions come up, post them here and I will do my best to explain. Enjoy!

Dave

[virtualpender]

Dave - I never made the connection that you were the author of the Visual Reference Guides. Thank you so much for publishing these! The Gato guide in particular is exceptionally useful. You work is very much appreciated!

[Ducimus]

As some of you have already noticed, the awesome website Navsource Naval History (www.navsource.org (http://www.navsource.org)) has published a series of articles called "A Visual Guide to U.S. Submarines". The index page with the articles can be accessed through this link:

http://www.navsource.org/archives/08/10idx.htm

(Insert shameless self-promotional plug here! :DL)


That is VERY interesting. I had no idea that Tambor/Gars orginally had a control room mounted periscope, nor that they sported 5/51 deck guns at one point in time.

[LukeFF]

Accordingly, radar detection and classification technology was non-existent on the IJN side and only in it's most primitive state in the USN. There was no ability classify and/or jam radars as there is today. Therefore, USN submarines could use their radars with virtual impunity. It would be a stretch to say that they left it on all the time, but nearly so.

The one exception to this was SD radar. Commanders started noticing a disturbing tendency for Japanese planes to start showing up when the SD radar set was turned on, so it became standard procedure to use it only intermittently:

In operating radars due consideration must be given to the possibilities of the SD radar signal being picked up by the enemy. Intermittent use of the SD for 5 seconds at irregular intervals of not more than one minute is considered to be fairly safe procedure.

When using the SD radar in enemy waters, turn on and off at irregular intervals, leaving it on 5 seconds and off 40 to 70 seconds.

http://ibiblio.org/hyperwar/USN/ref/SS-Doct/SS-Doct-2.html#section4

http://ibiblio.org/hyperwar/USN/ref/SS-Doct/SS-Doct-2.html#section5

[LukeFF]

And yes, let me add that those Visual Reference Guide articles are a great resource. I look forward to seeing your articles on the other classes.

[LukeFF]

Dave, with regards to the Gato, Balao, and Tambor/Gar classes, when was the transition made to the late war haze gray paint scheme?

[Sailor Steve]

Those are outstanding!:rock:

[virtualpender]

Luke, not to answer for Dave but Alden's "Fleet Submarines In The U.S. Navy" states that Measure 32 was required to be applied to all subs that did not already have it during their next refit beginning April 1944 (pg. 88).

Hope that helps.

[Jan Kyster]

Found this source collection yesterday: http://www.researcheratlarge.com/Ships/S19-7/index.html

Very interesting compilation of instructions, memos, counter-instructions, lost instructions :rotfl2:

[DaveyJ576]

Dave, with regards to the Gato, Balao, and Tambor/Gar classes, when was the transition made to the late war haze gray paint scheme?

I actually did not write the section on camoflage. The webmaster, Michael Mohl, inserted that part in there as it fit well with the theme of the other articles. I actually have not done a lot of research on the various camoflage schemes, but from what I have read the info contained in that section is quite good. For further info, refer to the references that I listed in the article.

[DaveyJ576]

The photo in Jan Kyster's post above is interesting. It shows a Gato class boat with a Mod 4 fairwater (low bridge, covered wagon ribs exposed, SJ radar mast forward of the shears). I can't see the limber hole pattern in the superstructure, but based on the angle of the trailing edge of the fairwater, this boat looks like a Government built version (Portsmouth or Mare Island.) This picture was probably taken in early to mid 1944. She has a 4"/50 cal deck gun in the forward position, a 20 mm mount on the forward fairwater gun deck, and a 40 mm on the cigarette deck. The interesting thing here is that on the aft deck gun position she has an additional 20 mm mount. This was sometimes done to gain additional firepower. Note that on both 20 mm mounts, the gun itself is missing. The Mk 10 Oerlikon 20 mm automatic cannon did not hold up well with repeated dunkings in saltwater, so the guns were removed from their mounts and taken below when not in use.

Jan, which boat is this?

[Jan Kyster]

Not even close, man! Photo was taken 21 August 1944! :smug:

It is USS Silversides (SS-236) outside Mare Island after an upgrade... sweet, isn't she? Buildt there too, btw.

[DaveyJ576]

Not even close, man! Photo was taken 21 August 1944! :smug:

It is USS Silversides (SS-236) outside Mare Island after an upgrade... sweet, isn't she? Buildt there too, btw.

Well I guess that depends on how you define "mid 1944"! I got really close! :D Much later than this date and most boats received a 5"/25 gun, although it appears Silversides finished the war with a 4"/50. That is unusual.

I did nail that it was a Government built boat, though! :smug:

[kraznyi_oktjabr]

Thanks for answer Dave! I got continuation question about radar. In SH4 vanilla version all fleet boats have rotating (radar?) antenna in port side of their fore deck. What this is?

[Sailor Steve]

Well I guess that depends on how you define "mid 1944"! I got really close! :D
I looked at the picture and said "Yep, that's a submarine all right!"
:rotfl2:

[LukeFF]

I got continuation question about radar. In SH4 vanilla version all fleet boats have rotating (radar?) antenna in port side of their fore deck. What this is?

That's the JP-1 sonar head.

[Ducimus]

That's the JP-1 sonar head.
Yup, on that note, Ptiy we can't make the FM sonar head work like its supposed to. :cry:

[Nisgeis]

However, as the USN operators got more and more experience with their new gear they found that it had an unintended capability. In February, 1945 the USS Batfish (SS-310) detected strange intermittent interference patterns on their SJ radar set. When an IJN submarine showed up a short time later, the crew of the Batfish concluded that it was radar sweeps from the submarine. They promptly dispatched the RO boat, and two others that were detected in the same fashion over the next three days.

Late war Japanese radar operated on the same frequency that US radar did, so radar equipped Japanese escorts were able to detect what bearing US submarines were on and were able to alter course away from them as a result (they would both receive interference on their scopes from the other's radar). The whole thing became a game of cat and mouse, with each side using their radar sparingly and the US radar operators 'keying' their radar sparingly. Each time the US sub used their radar, the Japanese convoy would alter course accordingly. Each time the Japanese used their radar, the US sub would get a bearing on their new position. When a correctly defended convoy operated like this, the convoy turned away and an escort came down the bearing of the radar. This coupled with the late war coast crawlers caused significant problems for US submarines.

[LukeFF]

Dave,

I don't know how familiar you are with Bauer and Roberts's Register of Ships of the U.S. Navy (very good book, BTW), but some info in there on the fleet subs has me curious. Namely, he lists the later fleet sub types (Gato, Balao, and Tench) as having a top submerged speed of 10 knots. Every other source I've ever seen lists a top speed of 9 knots. Do you know where that 10-knot speed possibly comes from?

http://btobsearch.barnesandnoble.com/Register-of-Ships-of-the-US-Navy-1775-1990/K-Jack-Bauer/e/9780313262029/?itm=1&USRI=register+of+ships+of+the+us+navy

[Diopos]

Rounding up????


:hmmm:

[LukeFF]

Rounding up????

Possibly.

Dave, while we're at it, I've come across a pic of an S-18 class submarine I've never seen before. I found it at the U.S. Navy and Marine Corps Museum Photo Archive (http://collections.naval.aviation.museum/emuwebdoncoms/pages/doncoms/Query.php), and it depicts an S-18 class sub at Dutch Harbor:

http://img.photobucket.com/albums/v258/LukeFF/SBoatAlaska.jpg

Any guess as to which boat it might be? The only 3 S-18s I know of that got a AA gun platform are S-28, S-31, and S-35. Also note the spray shield mounted on the bridge. Not something I've seen on any other S Class pics!

That site is really fascinating, showing some pics of American subs I've never seen before. Really worth checking out!

[DaveyJ576]

Late war Japanese radar operated on the same frequency that US radar did, so radar equipped Japanese escorts were able to detect what bearing US submarines were on and were able to alter course away from them as a result (they would both receive interference on their scopes from the other's radar). The whole thing became a game of cat and mouse, with each side using their radar sparingly and the US radar operators 'keying' their radar sparingly. Each time the US sub used their radar, the Japanese convoy would alter course accordingly. Each time the Japanese used their radar, the US sub would get a bearing on their new position. When a correctly defended convoy operated like this, the convoy turned away and an escort came down the bearing of the radar. This coupled with the late war coast crawlers caused significant problems for US submarines.

In this post Nisgeis is referencing a very interesting entry in the 4th war patrol report of the USS Baya (SS-318). See this link:

http://www.ussbaya.com/patrol4.html

The convoy commander in this incident was a very skilled operator and was able to take advantage of every tool at his disposal. Probably based on past experience, he was using interference on his radar screens to detect the prowling Baya and reroute his charges away. Most importantly, he took his job of Anti-Submarine Warfare (ASW) seriously. Unfortunately for the Japanese (and fortunately for the USN!) naval officers of his skill and temperament were few and far between. While it is documented that incidents like this did happen, they were fairly rare and for the most part, USN submarines could use their surface search radar with near impunity.

It is sometimes quoted that almost half of the late war IJN escorts had radar. While this somewhat murky statistic has some truth to it, one thing that must be considered is what type of radar they carried. There were three major types of radar at this point: surface search, air search, and gun fire control. Air search and gun fire control made up the majority of the radars installed on IJN ships and they operated on frequencies and possesed mechanical and operational limitations that made them very ill-suited (at best) or useless for detecting other ships. See this link and take a close look at the purpose and the installed platforms listed for each type:

http://www.combinedfleet.com/radar.htm

As you can see, very few of the dedicated surface search radars made it onto ASW ships. When they did, few officers and enlisted men had any knowledge or patience with the newfangled gadget and therefore the successful employment of this incredibly useful tool was limited at best.

I should have been clearer in my original post. There was indeed a strong suspicion that Japanese aircraft were detecting (probably through interference on their radios and own radars) the emissions of the SD air search radar used by our subs. Towards the end of the war, USN sub skippers began to use the SD on a limited basis for this reason. The surface search SJ, operating on different frequncies, seems to not have had the same issues.

[LukeFF]

Good writeup there on Japanese radar, Dave. The other thing to keep in mind was that, in general, Japanese radar was far less reliable than American types. The postwar technical research conducted by the Americans shows that, for instance, the Type 22 surface search radar was reliable only 80% of the time.

[DaveyJ576]

Dave,

I don't know how familiar you are with Bauer and Roberts's Register of Ships of the U.S. Navy (very good book, BTW), but some info in there on the fleet subs has me curious. Namely, he lists the later fleet sub types (Gato, Balao, and Tench) as having a top submerged speed of 10 knots. Every other source I've ever seen lists a top speed of 9 knots. Do you know where that 10-knot speed possibly comes from?

http://btobsearch.barnesandnoble.com/Register-of-Ships-of-the-US-Navy-1775-1990/K-Jack-Bauer/e/9780313262029/?itm=1&USRI=register+of+ships+of+the+us+navy

Actually, Diopos' answer to this question is probably correct. The authors of this book rounded up.

The two most authoritative authors, John D. Alden and Norman Friedman, list the max speed of these boats as 8.75 knots. Remember, this is the designed speed. Under real world combat situations, this speed was probably less. Most boats probably topped out at 8 knots. I have seen a few sources list the speed as high as 9.5 knots. The authors of the book in question probably saw this listed somewhere and for simplicity sake rounded up.

If you guys come across something on the technical side that sounds goofy, always refer to Alden and Friedman (with emphasis on Alden) for a quick fact double check.

[LukeFF]

The two most authoritative authors, John D. Alden and Norman Friedman, list the max speed of these boats as 8.75 knots. Remember, this is the designed speed. Under real world combat situations, this speed was probably less. Most boats probably topped out at 8 knots. I have seen a few sources list the speed as high as 9.5 knots. The authors of the book in question probably saw this listed somewhere and for simplicity sake rounded up.

If you guys come across something on the technical side that sounds goofy, always refer to Alden and Friedman (with emphasis on Alden) for a quick fact double check.

Thanks, Dave. I've been meaning to pick up Alden's book, so I just placed an order for a copy on Amazon.

[DaveyJ576]

Possibly.

Dave, while we're at it, I've come across a pic of an S-18 class submarine I've never seen before. I found it at the U.S. Navy and Marine Corps Museum Photo Archive (http://collections.naval.aviation.museum/emuwebdoncoms/pages/doncoms/Query.php), and it depicts an S-18 class sub at Dutch Harbor:

http://img.photobucket.com/albums/v258/LukeFF/SBoatAlaska.jpg

Any guess as to which boat it might be? The only 3 S-18s I know of that got a AA gun platform are S-28, S-31, and S-35. Also note the spray shield mounted on the bridge. Not something I've seen on any other S Class pics!

That site is really fascinating, showing some pics of American subs I've never seen before. Really worth checking out!

The following Electric Boat design S-boats (S-18 type) can be confirmed to have carried a raised AA gun deck aft of the conning tower fairwater as part of their wartime upgrades, as shown in Luke's photo above: 23, 28, 30, 31, 32, and 35. Insufficient photographic evidence exists to verify the configuration of the following: 34, 36, 37, 39, and 40. Based on the trends in what I have seen, it is unlikely that the boats higher than S-35 had this mod. The rest of the boats had completely different mods and did not have this AA gun platform, were leased to the RN and did not get these mods, or were lost or decommissioned prior to these mods being installed.

The structure on top of the bridge in the photo in question is actually a wind venturi. It was designed to deflect wind up and over the bridge watchstanders. It is an unusual configuration and can be used to narrow down the suspects. I found a photo of S-23 that nearly matches the one in the photo. Therefore, I will say, with a reasonably high degree of certainty, that the boat in the photo is S-23, with S-28 being a close 2nd.

How's that for a little detective work? :D

[LukeFF]

How's that for a little detective work? :D

Sounds good to me! Thanks!

[DaveyJ576]

Hey there!

I am currently working on "A Visual Guide to the U.S. Fleet Submarines Part 2: Salmon & Sargo Classes 1936-1945". Should be done and uploaded to Navsource in a week or so. This one took longer than I thought. Discovered some very interesting stuff!

I will let you know when it is done!

Dave

[LukeFF]

Hey there!

I am currently working on "A Visual Guide to the U.S. Fleet Submarines Part 2: Salmon & Sargo Classes 1936-1945". Should be done and uploaded to Navsource in a week or so. This one took longer than I thought. Discovered some very interesting stuff!

I will let you know when it is done!

Cool!

[Nuc]

Hey there!

I am currently working on "A Visual Guide to the U.S. Fleet Submarines Part 2: Salmon & Sargo Classes 1936-1945". Should be done and uploaded to Navsource in a week or so. This one took longer than I thought. Discovered some very interesting stuff!

I will let you know when it is done!

Dave


Great! I just read part 1 on the Gato. I'm sure there was a link in an earlier post but those who missed it (like me) here it is:

http://navsource.org/archives/08/pdf/0829294.pdf

[virtualpender]

Dave, can you explain the significance of the red arrow markings on the shallow depth gauge seen here? And why do these arrows vary from boat to boat, even in the same class?

http://i205.photobucket.com/albums/bb93/kikn79/USS_Cobia/Control%20Room/tn_DSCF5640.jpg

[DaveyJ576]

Dave, can you explain the significance of the red arrow markings on the shallow depth gauge seen here? And why do these arrows vary from boat to boat, even in the same class?

In this particular case, were the arrows moveable or were they permanently fixed in place?

[virtualpender]

The arrows are painted on the face of the gauge. That particular photo is from the COBIA but I saw similar markings on the shallow depth gauges of PAMPANITO a couple weeks back. I also dug up some photos online from COD and it also has the markings although they are at very different depths.

http://www.fleetsubmarine.com/graphics/224-cr-006.jpg


I'm very stumped. Your expert opinion is very welcome.

Also, I can't wait for your SARGO guide!

Thanks, Dave!

[Nuc]

Dave, can you explain the significance of the red arrow markings on the shallow depth gauge seen here? And why do these arrows vary from boat to boat, even in the same class?



Probably related to the operational depth for specific operations on that boat (e.g. certain radars, ECM masts, Snorkeling for Guppy conversions etc.)

[DaveyJ576]

To tell you the truth, this one kinda has me stumped. We didn't use any such markings during the Cold War on the Darter. The fact that they vary greatly from boat to boat belies one all encompasing explanation.

So my answer is this: they probably denote a variety of things, which would be determined by the specific boat's crew depending on what visual reference reminder they wanted for the planesmen. I agree with Nuc in that they may mean operational depths for specific operations. For instance, 48 feet would be about the depth that the bridge went under, leaving just the shears visible above the surface. 67 feet would be about the depth that the head of the periscope would dip under. These markings may also have a relationship to calculated buoyancy, i.e. the depth that you would flood or blow the negative or auxiliary tanks to achieve positive or negative buoyancy

[DaveyJ576]

Michael Mohl over at Navsource has posted Part 2 of the fleet boats article. here is the link: http://www.navsource.org/archives/08/10idx.htm

This part covers the Salmon and Sargo classes. Even though it only covers 16 boats, it ended up being just as long as Part 1. The modifications to these boats were more singular in nature and I found it necessary at some points to go boat by boat.

Next up will be the Porpoise/Shark/Perch class. Due to an upcoming move to New York, that one will not hit the streets until late summer.

Enjoy! :)

[Diopos]

---
And a question regarding The Plotting Party... if you please? :D

...

Maybe this (http://www.subsim.com/radioroom/showthread.php?t=161283) is of some help...:hmmm:




.

[LukeFF]

Michael Mohl over at Navsource has posted Part 2 of the fleet boats article. here is the link: http://www.navsource.org/archives/08/10idx.htm

This part covers the Salmon and Sargo classes. Even though it only covers 16 boats, it ended up being just as long as Part 1. The modifications to these boats were more singular in nature and I found it necessary at some points to go boat by boat.

Next up will be the Porpoise/Shark/Perch class. Due to an upcoming move to New York, that one will not hit the streets until late summer.

Enjoy! :)

Great job, as always! :) As for the lack of info about Mod2/2A for these boats, I've read through the patrol reports for the Salmon and Sargo class boats and found very little evidence of this mod being applied to these classes. It may be that the majority of these boats simply "jumped' over these early mods and were modified from their original form into Mod 3.

I've not read entirely through the PDF file yet, but did you cover the deck-mounted torpedo containers at all?

[DaveyJ576]

Great job, as always! :) As for the lack of info about Mod2/2A for these boats, I've read through the patrol reports for the Salmon and Sargo class boats and found very little evidence of this mod being applied to these classes. It may be that the majority of these boats simply "jumped' over these early mods and were modified from their original form into Mod 3.

I've not read entirely through the PDF file yet, but did you cover the deck-mounted torpedo containers at all?

Your conclusion concerning these boats jumping over the Mod 2 and 2A's is entirely plausible. By the time that most of the Salmon/Sargos returned for their first overhauls the Mod 3's were already in vogue and they may have gone from a Mod 1 directly to the Mod 3. As I gather new info like this, I will incorporate it into the articles via revisions.

I puzzled for a bit over why the SJ radar was consistantly mounted on the starboard side of the shears as opposed to forward as in the Gatos. Then it suddenly hit me. In order to get a useful range, the dish had to be mounted fairly high above the water. This height also dictated how high the support bracket for the SJ mast had to be mounted. On the Gatos this was not a problem. The support shear for #1 scope provided the perfect height to mount this bracket. However, on the Salmon/Sargos with their 34 foot #1 scope, this shear was not high enough so the bracket was attached to the #2 scope shear. If they had placed the radar mast in the traditional location forward of the scopes, this support bracket would have been in the way of the #1 scope and would have prevented raising or lowering it. The solution was elegantly simple, attach the SJ bracket to #2 scope shear, just move it out of the way to starboard. This seemed to work quite well, as only 6 of the 16 boats had the radar moved to a "normal" location, even after receiving a 40 foot #1 scope. Interesting

Only one Salmon/Sargo boat had deck mounted, external launching tubes, the Stingray (SS-186) and I documented that in the article. As for the stowage tubes that were mounted inside the superstructure forward of the conning tower I have yet to turn up good information on their configuration. The thrust of the article was on visually identifying the boats and since these stowage tubes can not be seen from the outside I did not cover them. However, I have not given up. I am working on obtaining a set of plans for these boats that may show how these tubes were configured. Got to find the dough, though and that is in short supply right now. :x Soon I hope!

[LukeFF]

Dave,

On the fleet submarines, how much of an effect did the trim and drain pumps have on a boat's ability to maintain a given depth? Could a boat maintain a certain depth at All Stop, given that the pumps were in operation?

[DaveyJ576]

Dave,

On the fleet submarines, how much of an effect did the trim and drain pumps have on a boat's ability to maintain a given depth? Could a boat maintain a certain depth at All Stop, given that the pumps were in operation?

The technology of the 1940's was not capable of creating a ballast control system precise enough to enable a fleet boat to hover. Achieving perfect neutral buoyancy is very difficult even with today's computerized systems. There are dozens of factors that have to be constantly monitored and adjusted for in order to maintain the desired level of buoyancy. As an example, one crewman that moves from the crew's mess to the forward torpedo room will make the boat heavy forward. Water will have to be pumped from the forward trim tank to the after trim tank to compensate. Other factors that effect buoyancy are temperature and salinity of the water, currents, surface wave action, fresh water production, fuel useage, loading torpedoes, leaking shaft seals, battle damage, etc. The diving officer and the trim & drain manifold operator have to constantly monitor all these factors and compensate for them.

Everything on these boats was done by hand. To pump water from forward trim to after trim for example, the manifold operator opened the valve for the fwd trim tank using a large T-shaped wrench. He then pushed a button to start the trim pump. Once a suction on the tank was achieved, he would transfer the wrench to the valve for the after trim tank and open it. His eyes would then be glued to a flow gauge that was calibrated in pounds of sea water and would call out to the diving officer as each 100 pounds was transferred. Once the diving officer was satisfied with the amount transferred he would have the manifold operator secure the system. Neither the flow gauge nor the trim pump was sensitive enough to move amounts less than about 100 pounds.

Even if you were able to achieve perfect neutral buoyancy you would not be able to maintain it for very long due to the factors that I mentioned above. Strange as it may sound, these boats were not 100% watertight 100% of the time and that effected your ability to maintain neutral buoyancy. For safety purposes most diving officers trimmed their boats slightly light and used plane action to maintain depth.

Also, since the trim and drain pumps made noise, they were used only when absolutely necessary during battle. Most diving officers waited until the planesmen had trouble maintaining depth before they used them.

So, to sum up, the trim and drain pumps were not constantly in use and perfect neutral buoyancy was very difficult to achieve and maintain. If a boat came to all stop while submerged, it would usually either rise or sink depending on its' state of buoyancy at that time.

[LukeFF]

Excellent reply as always, thanks!

Strange as it may sound, these boats were not 100% watertight 100% of the time and that effected your ability to maintain neutral buoyancy. For safety purposes most diving officers trimmed their boats slightly light and used plane action to maintain depth.

Yep, the Fleet Sub manual makes mention of the fact (in the trim and drain pump section) of all the different areas where water could and did leak into the boat.

[DaveyJ576]

A revised version of "A Visual Guide to the U.S. Fleet Submarines Part One: Gato Class" has been posted on Navsource.

http://www.navsource.org/archives/08/10idx.htm

I reformatted the article for better readability and added some new information. Based on the inputs from readers, I added a new mod, the Mod 1A. I also updated the Mod 2 and Mod 3 sections, and added information that I found concerning a one off variation to the Gato herself. This is probably the final version for this particular article, but if previously unknown info turns up, who knows?

[Sailor Steve]

Awesome stuff! I've looked at those from time to time, and never realized that was you. Thanks for that great site! :salute::rock:

[virtualpender]

Thanks for the update. This is tremendously interesting and helpful information you have published for all of us. Thank you.

[Subnuts]

Not really sure if this has been posted yet, but this site includes PDF versions of 16 sets of general plans for American submarines ranging from the USS Holland (SS-1) to USS Growler (SSG-557). The Tang contract plans are worth checking out if you're seriously interested in submarine design and construction.

[/URL][URL="http://www.hnsa.org/doc/plans/index.htm"]HNSA - Booklet of General Plans (http://www.hnsa.org/doc/plans/index.htm)

[DaveyJ576]

I looked over with a great deal of interest the webpage that Subnuts referenced above. In particular the plans for the Guppy boats Catfish & Dogfish (Guppy II), and Razorback (Guppy IIA) caught my eye. The plans for the Guppy II boats had a discrepancy that I initially could not explain.

The Guppy II boats were basically a Guppy I with a snorkel. To get the extra power needed for the greatly desired higher submerged speeds, both batteries were expanded to four sets of 126 cells each. The existing forward and after battery wells were too small to accomodate this new arrangement so a new smaller battery cell was developed. Even this measure was not enough so the after battery was extended into the now superfluous ammo magazines under the crew's mess and the forward battery was expanded into the pump room under the control room. This presented a problem as the drain pump, air conditioner plants, and air compressors located there were still vitally needed machinery. The solution was to remove the unneeded auxiliary diesel from its' location below the deck plates in the after engine room and relocate this gear there. This proved to be a very cramped arrangement and proper maintenance of this gear was very difficult. The Guppy II boats retained all four of their main propulsion diesels.

The greatly expanded and modernized sonar gear for these boats simply would not fit in the already crowded conning tower or control room. The solution was to build a new sonar room in the aft port corner of the forward torpedo room. Unfortunately, this arrangement meant that only shorter ASW torpedoes like the Mk-37 could be carried in the port stowage racks, effectively reducing the amount of the big torpedoes (Mk-14 and Mk-16) that could be carried. The Guppy II conversion was also quite expensive and the Navy wanted to find a way to cut costs so that more of the fleet boats could be converted.

One of the solutions was the Guppy IIA. The major difference was in the battery. In a timely development a much more powerful (and cheaper) battery cell design using the same size of the original came into service and this allowed a power output similar to the Guppy II battery without having to expand the size of the battery wells. This development, along with the desire to regain the lost space in the forward torpedo room led the designers to move the sonar room to the forward half of the pump room. Once again, the A/C, air compressors, and drain pump had to be moved. The cramped arrangement of the Guppy II's in this regard led to the radical solution of removing #2 main propulsion diesel from the forward engine room and placing the machinery from the pump room in its' place. This obviously had the effect of lowering the surface speed, but since these boats were going to be spending a lot more time submerged than in the past, the loss of approximately 4-5 knots in surface speed was not considered critical.

As I was looking over the plans shown for the two Guppy II boats, I noticed that both showed that #2 main engine had been removed with the displaced pump room gear relocated in its' place. This ran contrary to all the listed specs for these boats in my reference materials. I scratched my head on this one for a while until I came across a paragraph in Norman Friedman's book U.S. Submarines since 1945.

By the mid 1960's, the need to increase the effectiveness of the sonar systems on the Guppies to counter the rising Soviet threats led to some measures to silence these fairly noisy boats. Own ship generated noise made it hard for the sonar operators to hear anything, especially when snorkeling. The solution was the Masker system. It bled air from small ports in the hull forward of the engine rooms and along the bilge keel. These small bubbles mostly masked the noise from the engine rooms from the sonar gear located forward. The propellers also generated noise and another system called Prairie forced air through tiny holes in the propeller blades and this greatly reduced their noise output. The large compressors needed for these systems had to go somewhere and in a manner similar to the Guppy IIA's, #2 main engine was removed from the Guppy II's and the compressors placed there. This also led to the happy move of the gear previously displaced from the pump room to this location as well, greatly easing the maintenance problems encountered in the after engine room.

John Alden's book The Fleet Submarine in the U.S. Navy made no reference to this and Friedman's book only had one small obscure paragraph that I had previously missed. None of my other references mentioned this 1960's modification to the Guppy II's either. But if you look at the plans closely, you can see the Prairie/Masker compressors labled in the forward engine room. I didn't realize that this was a later addition to the Guppy II's

The history of the development of the Guppy modifications is quite interesting and well worth a read. I would recommend either of the two books I listed above.

[EFileTahi-A]

Hello I'm in designing phase for a WWII sub game I wish to do. At the momment I'm taking care of the game's UI (using windows controls only). I am in great need of understanding some aspects of WWII u-boats related to torpedoes.

1 - The torpedo loading sequence.
How long to load a torpedo? How many crew members were involved in such task?

2- The torpedo's setting for bearing, speed and depth.
Does this requires the torpedo to be out of the tube?

3 - The torpedo firing sequence.
What happens once the inner door is closed? Is the torpedo flooded when opening the outer door? How long does it take to flood the tube?

4 - Unloading a torpedo which was already flooded.
How long to empty a flooded tube?

Thank you.

PS: if someone is interested in the project, please do let me know. I will gladly describe what I intend to do.

[DaveyJ576]

I am in great need of understanding some aspects of WWII u-boats related to torpedoes.

Keep in mind that all answers that I give will be related to operations aboard the USN fleet submarines. Specific procedures will vary somewhat in other navies, although in principal it will be very similar.

1 - The torpedo loading sequence. How long to load a torpedo? How many crew members were involved in such task?

This is a factor that will vary greatly depending on the level of proficiency of the torpedo room crew. Using a system of ropes and pulleys (block and tackle) a well trained crew of about 4-6 Torpedomen will be able to load a tube in approximately 5-8 minutes. A USN Mk-14 torpedo weighs a little over 3,000 lbs! Whenever possible, the Diving Officer will order the planesmen to hold a slight down angle (or up angle if it is the stern tubes) to assist the Torpedomen in their efforts.

2- The torpedo's setting for bearing, speed and depth. Does this requires the torpedo to be out of the tube?

Once the torpedo was loaded in the tube, setting spindles were engaged to ports on the weapon. The Torpedo Data Computer, which constantly tracked the target's course, speed, range, and angle on the bow set the gyro angle on the weapon and automatically updated it right up to the moment of firing. Other spindles set the running depth and speed of the weapon, although the low speed feature of the Mk-14 was rarely used. These spindles are disengaged as part of the firing sequence. This ability to automatically and remotely set these parameters was a tremendous advance in capability for the USN.

3 - The torpedo firing sequence.
What happens once the inner door is closed? Is the torpedo flooded when opening the outer door? How long does it take to flood the tube?

Once the weapon is in the tube and the spindles engaged, the inner (breech) door is shut and locked. Water is flooded into the tube from the Water 'Round Torpedo (WRT) tank with the remaining air in the tube vented into the room. An equalizing valve is then opened to ensure the interior of the tube is at the same water pressure as the outside of the boat. The outer (muzzle) door of the tube can then be opened. A good Torpedoman takes pride in how fast he can make the tube ready to fire, the process to this point will take approximately 30-45 seconds.

To fire the tube, a shot of high pressure air is fired into the aft part of the tube behind the weapon, pushing it out of the tube. Before the air bubble can escape the tube and give away the boats' position, a poppet valve opens which vents the air back into the room, this process is assisted by the water which floods back into the tube from outside. The muzzle door is then shut. The water in the tube is then drained back into the WRT tank with the excess volume going into the forward trim tank. This compensates for the loss of the weight of the torpedo. Once drained, air pressure in the tube is equalized with that of the torpedo room and the breech door is opened. An interlock system prevents the breech door and the muzzle door from being opened at the same time.

4 - Unloading a torpedo which was already flooded. How long to empty a flooded tube?

Draining the tube after firing takes a little longer than flooding it, approximately 45 seconds to one minute. If you didn't fire the weapon and had to unload it from the tube, just reverse the procedure that I described above. It will take a similar amount of time.

Did I answer all of your questions? I will defer to someone else on the specific procedures for U-boats. They did differ somewhat from the USN.

[GerritJ9]

Great topic, with lots of useful info indeed!:up:
Regarding the transfer of torpedoes from aft to forward as discussed on page 11, it is perhaps interesting to note how HMS "E-11" recovered torpedoes that had missed their target during her first patrol in the Dardanelles/Sea of Marmora in 1915. Torpedoes were set to float when their fuel was expended if they missed; when the coast was clear, the sub would surface and search for the torpedo. When found, a brave chap would dive overboard, swim to the torpedo and unscrew the firing pistol. On the first occasion the torpedo was hoisted on deck, the warhead removed and warhead and torpedo body then lowered into the boat separately through the fore hatch in the usual manner. On the next occasion, however, the boat was trimmed until the aft tube was awash; the outer door was opened and the torpedo guided warhead first into the tube, the outer door closed; then the inner door was opened, revealing the warhead. After that it was "simply" a matter of transporting the torpedo to the bow torpedo space- presumably, the internal arrangement of "E-11" did not make this too difficult. See "Dardanelles Patrol" by Peter Shankland and Anthony Hunter.
Of course, Turkish anti-submarine capabilities were nowhere near even those of the Japanese- one can hardly imagine any Allied sub being able to do this off the coast of Honshu or in Malacca Strait and get away with it...........

[EFileTahi-A]

Keep in mind that all answers that I give will be related to operations aboard the USN fleet submarines. Specific procedures will vary somewhat in other navies, although in principal it will be very similar.



This is a factor that will vary greatly depending on the level of proficiency of the torpedo room crew. Using a system of ropes and pulleys (block and tackle) a well trained crew of about 4-6 Torpedomen will be able to load a tube in approximately 5-8 minutes. A USN Mk-14 torpedo weighs a little over 3,000 lbs! Whenever possible, the Diving Officer will order the planesmen to hold a slight down angle (or up angle if it is the stern tubes) to assist the Torpedomen in their efforts.



Once the torpedo was loaded in the tube, setting spindles were engaged to ports on the weapon. The Torpedo Data Computer, which constantly tracked the target's course, speed, range, and angle on the bow set the gyro angle on the weapon and automatically updated it right up to the moment of firing. Other spindles set the running depth and speed of the weapon, although the low speed feature of the Mk-14 was rarely used. These spindles are disengaged as part of the firing sequence. This ability to automatically and remotely set these parameters was a tremendous advance in capability for the USN.



Once the weapon is in the tube and the spindles engaged, the inner (breech) door is shut and locked. Water is flooded into the tube from the Water 'Round Torpedo (WRT) tank with the remaining air in the tube vented into the room. An equalizing valve is then opened to ensure the interior of the tube is at the same water pressure as the outside of the boat. The outer (muzzle) door of the tube can then be opened. A good Torpedoman takes pride in how fast he can make the tube ready to fire, the process to this point will take approximately 30-45 seconds.

To fire the tube, a shot of high pressure air is fired into the aft part of the tube behind the weapon, pushing it out of the tube. Before the air bubble can escape the tube and give away the boats' position, a poppet valve opens which vents the air back into the room, this process is assisted by the water which floods back into the tube from outside. The muzzle door is then shut. The water in the tube is then drained back into the WRT tank with the excess volume going into the forward trim tank. This compensates for the loss of the weight of the torpedo. Once drained, air pressure in the tube is equalized with that of the torpedo room and the breech door is opened. An interlock system prevents the breech door and the muzzle door from being opened at the same time.



Draining the tube after firing takes a little longer than flooding it, approximately 45 seconds to one minute. If you didn't fire the weapon and had to unload it from the tube, just reverse the procedure that I described above. It will take a similar amount of time.

Did I answer all of your questions? I will defer to someone else on the specific procedures for U-boats. They did differ somewhat from the USN.

Man.. thank you so very much! Though I understand that this info is USN related, I does let me get the general picture of such aspects. Having also in count that the player will be able to play to the USN side, the information you shared with me is indeed double perfect!

Can I ask you about the math formula used to compute the path of a torpedo torwards a target? I know I need speed, distance and angle of the target relative to the player's sub position and bearing. It is too complicated?

Thanks again!

[DaveyJ576]

Can I ask you about the math formula used to compute the path of a torpedo torwards a target? I know I need speed, distance and angle of the target relative to the player's sub position and bearing. It is too complicated?

Thanks again!

There are several excellent threads on this forum concerning game related torpedo fire control. Rockin Robbins in particular has a very good handle on this issue. Take a look at those threads and you will find all that you need.

[EFileTahi-A]

There are several excellent threads on this forum concerning game related torpedo fire control. Rockin Robbins in particular has a very good handle on this issue. Take a look at those threads and you will find all that you need.

Well didn't managed to find anything. Anyway this will be addressed later on. It is not important at the moment.

Thanks anyway.

[DaveyJ576]

Well didn't managed to find anything. Anyway this will be addressed later on. It is not important at the moment.

Thanks anyway.

Try this: http://www.subsim.com/radioroom/showthread.php?t=146795

It should have just about everything you want to know.

[Admiral8Q]

Davey, I have a mechanical question. Did the WW2 fleet boats use gears, a transmission system like in cars? Or was it just more fuel means more speed. Submerged I'd guess that it was just more electricity means a faster screw speed.

[magic452]

The screws were turned by electric motors on the surface and submerged.
The diesels just powered generators that ran the motors and/or charged batteries. The diesels were governed at the most fuel efficient RPM and speed control was done with the electric motors. The number of diesels run was dependent on the speed selected. 1/3 ran one diesel, 2/3 two diesels, standard was three and ahead full used all four. Ahead flank added battery power to the generators. At lease that is how I understand it.

Magic

[Admiral8Q]

Yes, come to think of it, I remember something already explained about that earlier in this thread. So the diesels were just generators basically I guess, not providing thrust to the screws, but indirectly pumping electricity into the electric batteries and motors.

Interesting.:hmmm:

[Shado]

Hello all,

I was wondering, if anyone knows about what speed did the subs use to trasit to their patrol areas? Would they use standard or something faster. I have read some of the actual patrol logs, but don't remember seeing a speed they use to transit. I remember some depths they used when submerged during the day.

Thanks

[Diopos]

Hello all,

I was wondering, if anyone knows about what speed did the subs use to trasit to their patrol areas? Would they use standard or something faster. I have read some of the actueal patrol logs, but don't remember seeing a speed they use to transit. I remember some depths they used when submerged during the day.

Thanks

Submarine specifications usually include a parameter such as:
Cruising range: 11,000 miles @ 10 knots (surfaced)

Keep your "cruising" speed at 9-10 knots to preserve fuel/maximize range.


.

[Shado]

Thanks for the info.
It did not click in my head that that speed and range was the cruise range. Makes sense though.
Again thanks for the reply

Dive dive dive

see ya in port

[aergistal]

Looking at the patrol report of USS Wahoo I noticed they attacked a ship identified as Tottori Maru. Weren't those hell ships carrying allied POWs? I thought many of those were sunk because they didn't know they were hell ships in the first place. But why fire on an identified POW ship?

[Nisgeis]

How would they know what the cargo was? The Japanese didn't identify their POW ships with the correct markings or lights. The same ships that transported POWs were also used to transport horses, sugar, munitions... anything that was needed.

[Arclight]

Weren't most of the ships identified after the attacks, by investigating intercepted radio-traffic or even documents captured atfter the war?

Identify the class/type of ship sure, but seems difficult to pick out individual ships.

[aergistal]

Double checked that and altough it's identified as Tottori Maru in the attack table in the description of the attack is reported "similar to the Tottori Maru".

[John Channing]

One thing I have alway wondered was if US boats had a way of measuring doppler effect during WWII?

JCC

[Platapus]

One thing I have alway wondered was if US boats had a way of measuring doppler effect during WWII?

JCC


The technology and knowledge was there during WWII to use and measure the doppler effect of radar. Whether this was ever implemented on a ship or submarine, I have not been able to find out.

My guess would be no, but I will continue to dig

[John Channing]

I was thinking of the doppler shift effect as it pertains to sound. In post-war boats and destroyers it is one of the most important methods of dealing with an unknown contact, but it has never been implemented in any sim. I was just wondering if they could measure it as far back as WWII, or is it a more recent innovation.

JCC

[Nuc]

As I recall there were some limitations on speed that are ignored in SH4. Wasn't there a limit on the maximum speed at which:

a. periscope could be raised?
b. outer doors could be opened?

[Ducimus]

I don't know if this has been asked before, but how long would it take a fleet submarine (such as a Gato) to do a full battery charge if:

a.) It had 1 engine one the charge?

b.) If it had 2 engines on the charge?

Thanks in advance.

[Aviv]

Hello all, interesting thread ;)

I'm not sure if it was already asked, but I wanted to know:
How much food did a submarine take? How long could it last on the food it brought? Also, what kinds of food did they eat on board?

All these food questions, I guess I must be hungry..
Thanks and answers appreciated!

[sergei]

Quick question.
Late in the war RWR gear was made available to fleetboats.
Was it directional?
ie. did it give a bearing to the enemy radar, or just let you know there was an enemy radar out there somewhere?

[Stealhead]

I am no expert but I recall reading in I think it was "Thunder Below" in there somewhere Fluckey mentions the RWR only letting you know that radar was present but nothing beyond that.

Of course I have read tons of other books on fleet boats so it might have been in another book.

Edit: after looking in "U.S. Submarines Through 1945" I found a section on some units,DBV and DBU that could tell the operator if a detected radar signal was coming from port or starboard.It seems that these RWR units where not around until late 1945 though so it seems the RWR available during the war lacked directional ability as the DBV and DBU added the directional ability and where improvements for earlier units that lacked this ability it seems that the DBV and DBU units where too late for WWII to see much/any use in WWII.

[sergei]

Roger that.
Thanks Stealhead.

[DaveyJ576]

To all:

I apologize for the long time away. The Navy has kept me busy.

I loathe conspiracy theories. While interesting and sometimes thrilling, they invariably are based on half-truths, innuendo, poorly understood technical issues, or plain out-and-out falsehoods. There is also frequently a hidden agenda by the person putting forth the theory. I rarely weigh in on them because it is like arguing with a brick wall.

There has been discussion in the past here in these forums concerning the loss of the USS Scorpion (SSN-589). Conspiracy theorists have tried to explain her loss by blaming the Soviets. It is said that the Soviets deliberately sank her because she either spied on some "nearby" naval maneuvers, or in retaliation for the perceived deliberate sinking of a Golf class missile boat in the Pacific. These theories are complete nonsense and have no real basis in facts or truth.

Due to the nature of her sinking, no one will ever be able to definitively say what sank her. However, several theories have been put forth that are based on known facts, thorough research, and informed technical speculation by experts. I will quote below a letter that I received from a contact of mine. While still admittedly a theory, it is well founded and based on observed evidence and fact. Addresses in the to and from lines have been redacted by me for privacy purposes, other wise the body of the letter is intact.


6 August 2010

From: B. Rule
To: VADM David J. Dorsett, Director of Naval Intelligence, Office of Naval Intelligence,

Subj: Why the USS SCORPION (SSN-589) Was Lost on 22 May 1968

Ref: (a) Originator’s ltr of 14 Mar 2009
(b) SCORPION SAG Report: "EVALUATION OF DATA AND ARTIFACTS
RELATED TO THE USS SCORPION (SSN-589) (U)" of 29 June 1970,
prepared for presentation to the CNO SCORPION Technical Advisory Group by
the Structural Analysis Group: Peter Palermo, CAPT Harry Jackson, Robert
Price, et al.
(c) Originator’s ltr of 28 Oct 2009

Encl: (1) Enclosure (1) to Originator’s ltr of 14 March 2009

ASSESSMENT

The USS SCORPION was lost because hydrogen produced by the 65-ton, 126-cell TLX-53-A main storage battery exploded in two-stages one-half second apart at 18:20:44Z on 22 May 1968. These events, which did not breach the pressure-hull, prevented the crew from maintaining depth-control. As discussed by reference (a), the SCORPION pressure-hull collapsed at 18:42:34Z at a depth of 1530-feet. Noted times are actual event times on board SCORPION.

This assessment is NOT the generic attribution of the loss of a submarine to a battery-explosion advanced as a default explanation in the absence of any more likely construct. This assessment is based on (1), the results of examination and microscopic, spectrographic and X-ray diffraction analyses of recovered SCORPION battery material that confirm an explosion occurred, and (2), the July 2008 reanalysis of the SCORPION “precursor” acoustic signals that identified these signals as explosions contained within the SCORPION pressure-hull. Collectively, these findings indicate battery explosions were the initiating events responsible for the loss of SCORPION on 22 May 1968.

DISCUSSIONS: EXAMINATION AND METALLURGICAL ANALYSIS OF A RECOVERED SCORPION BATTERY COMPONENT

Section 7.1.3, page 7.2 of reference (b) states: (quote) ....the general battery damage is violent. The high velocity intrusion of pieces of the flash arrestor into both inside and outside surfaces of the retrieved plastisol cover attest to violence in the battery well. The damage to the terminal battery post coupled with the violent tearing of the plastisol covers indicates the possibility of a battery explosion. While it is possible that this damage could have been an after-effect of hull implosion, the SAG (Structural Analysis Group) feels that the intrusion of particles into the plastisol cover would have been much less severe had water been in the battery well at the time. (end quote)

Section 5.3.6, page 5.17 of reference (b) states: (quote) The battery installed in SCORPION was a TLX-53-A, manufactured by Gould-National Battery, Inc. Battery cell debris is in evidence over the entire debris field. Table 5-2, page 5.38 provides a list of the battery debris identified by the Portsmouth Naval Shipyard analysis team. (end quote) Comment: Table 5-2 notes damage from heat and melting. The presence of melting eliminates the possibility that such damage occurred as a result of pressure-hull collapse (implosion) because analysis of acoustic data discussed by Section IV of reference (c), confirms SCORPION was fully-flooded within 0.112-seconds of pressure-hull and bulkhead collapse; hence, the melting damage (and the battery explosion) had to have occurred within the still-intact SCORPION pressure-hull.

In consonance with this conclusion, Section 5.3.6, page 5.17 of reference (b) also states: (quote) the Portsmouth Naval Shipyard Analysis Group reports that the available evidence indicates the battery probably exploded at some time before flooding of the battery well occurred. Review of Figure 5-13 indicates that the threads on the terminal posts were sheared off and there are no cover seal nuts remaining. This indicates that an explosion took place on the inside of the cells. The covers were completely blown off. Had the pressure been applied on the outside of the covers, the cover support flange on the terminal posts would have held pieces of the covers and it is expected that the cover seal nuts would have remained in place in at least some instances. ( end quote)

Further, Section 5.3.6c, page 5.18 of reference (b) states: (quote) The (battery cover) sample from SCORPION had been violently, but locally, torn, particularly at the location of the bus connection bolts and nuts. The deformation in this region appears to have started on the inside, or battery side of the cover. (end quote)

And finally, Section 5.3.6e, page 5.18 of reference (b) states: (quote) Some 20 equally small (nearly sub-visible) fragments of material were imbedded at high velocity in both the inside and outside of the sample. The trajectories of the fragments were essentially random, ranging from grazing to vertical incidence. Microscopic, spectrographic and X-ray diffraction analyses reveal that these fragments are identical in composition and structure to the alumina flash arrestors used on the batteries in SCORPION. (end quote)

DISCUSSIONS: SCORPION ACOUSTIC DATA

Enclosure (1) to reference (a), forwarded as enclosure (1) to this letter, provides detailed discussions of four independent lines of evidence that, collectively, established, for the first time, that the two “precursor” acoustic events that occurred at 18:20:44Z, 21-minutes and 50-seconds before hull-collapse, were explosions from then unidentified sources that were contained within the SCORPION pressure-hull. The energy yield of these explosive events, now assessed to have been battery-associated, is estimated to have been no more than about 20-lbs of TNT each.

The July 2008 identification of the precursor acoustic events as explosions contained within the SCORPION pressure-hull strongly supports the battery explosion conclusion advanced by reference (b), i.e., the acoustic data identifies the actual explosive events previously assumed by the authors of reference (b), the SAG Report, to have occurred based on the observed damage to a recovered battery component discussed above.

CONCLUSION

Collectively, the above information indicates the two acoustic events that occurred 0.5-seconds apart at 18:20:44Z were produced by explosions associated with the SCORPION TLX-53-A battery, and were the initiating events responsible for the loss of SCORPION on 22 May 1968. Additional information will be provided as developed.

B. Rule
Copy to (w/ encl):
COMSUBFOR


What does all this mean? Nuclear submarines have batteries that act as a back up source of power in case of a reactor shutdown. The battery on the Scorpion was similar to, but smaller than the battery on a fleet boat. Charging the battery, or a short circuit, will produce extremely explosive hydrogen gas. If not properly vented, this gas will accumulate and eventually explode, violently. This type of explosion could have easily killed crewmen and disrupted control of the boat long enough to send her crashing through crush depth.

The other leading theory explaining her loss is also battery related. The Scorpion carried Mk-37 torpedoes on her last voyage. These are 19 inch swim out weapons powered by electric batteries. Early versions of this weapon (like the ones carried by Scorpion) had a defect in the battery design that could lead to overheating of the battery (even while the weapon sat inert on the skid inside the torpedo room). If the battery got hot enough, tests showed that it could trigger a low-order (partial) detonation of the warhead, powerful enough to cause havoc inside the boat but not powerful enough to breach the hull.

Seeking the truth is an admirable endeavor and I encourage it. But rampant, ill-informed, or agenda based speculation does nothing but obscure the truth.

The loss of the Scorpion was nothing more than a tragic accident. There is nothing sinister about it and there is no conspiracy. Let these shipmates rest in the peace that they have earned.

[Sailor Steve]

Welcome back!

I loathe conspiracy theories. While interesting and sometimes thrilling, they invariably are based on half-truths, innuendo, poorly understood technical issues, or plain out-and-out falsehoods. There is also frequently a hidden agenda by the person putting forth the theory. I rarely weigh in on them because it is like arguing with a brick wall.
Interesting story. As a friend of mine once pointed out, it takes an untold number of people to keep a conspiracy secret, and only one to blow the lid off it. As long as people are still speculating, speculation is all it is.

[Barkhorn1x]

Interesting story. As a friend of mine once pointed out, it takes an untold number of people to keep a conspiracy secret, and only one to blow the lid off it. As long as people are still speculating, speculation is all it is.

Excellent observation - and a corollary is; “The length of time a secret is kept is in inverse proportion to the magnitude of the secret.” It’s human nature to blab – and this fact renders ALL the major PCTs (Paranoid Conspiracy Theories) false - as no one spills the beans - Occam’s Razor aside.

[Stealhead]

There is a book out there that I have seen that is at least partly to blame for the Soviets having attacked the Scorpion conspiracy I dont recall the name right now but I have seen it in book stores before.I thumbed through it and was not impressed at all.But I am sure others believe what the book claims to be true unfortunately.

My Grandmother used to say dont believe anything you read and only half of what you see.Good advice.

[sergei]

The Scorpion carried Mk-37 torpedoes on her last voyage . . . Early versions of this weapon (like the ones carried by Scorpion) had a defect in the battery design that could lead to overheating of the battery . . . If the battery got hot enough, tests showed that it could trigger a low-order (partial) detonation of the warhead

I've read a few books where this was posited as the most likely explanation for the loss of the Scorpion.

[Rip]

I have listened to the "precursor" events myself. I would agree it was nothing but an accident. But like all of our tragic submarine accidents they have saved countless others in their death. James Calvert pointed out in his book "Silent Running" that he thought the loss of the Squalus saved his life by demonstrating the need for a back up flapper valves for the diesel intakes.


Rest in peace shipmates, we are eternally grateful for your sacrifice!

Rip

[Sensekhmet]

Not to come off as a jerkass and go too far off topic but how is dying in an accident a sacrifice? I agree that if things are learnt from it it's 'not dying in vain' but when saying 'sacrifice' I think 'dying knowingly and willingly for a reason or cause'.
I apologize if I offended anyone but that's just me thinking aloud: I'm Polish so these questions are rather close to me lately after Smolensk.

[Sailor Steve]

Not to come off as a jerkass and go too far off topic but how is dying in an accident a sacrifice? I agree that if things are learnt from it it's 'not dying in vain' but when saying 'sacrifice' I think 'dying knowingly and willingly for a reason or cause'.
I apologize if I offended anyone but that's just me thinking aloud: I'm Polish so these questions are rather close to me lately after Smolensk.
Not offended nor trying to offend in return. I think the idea is that if the business you are in is risky then you live with the knowledge that you could die in the line of duty, so the living is itself inviting the potential for an unusual death.

Secondly, if someone can learn from the accident and can prevent it from happening again, then your death helped save others' lives and that can be considered a sacrifice, whether you willingly invited it or not.

I'm not saying that's the correct answer; just speculating.

[Diopos]

...

I'm not saying that's the correct answer; just speculating.

It's the correct answer.

[Stealhead]

Yes I agree as well very good answer.

[Rip]

Not offended nor trying to offend in return. I think the idea is that if the business you are in is risky then you live with the knowledge that you could die in the line of duty, so the living is itself inviting the potential for an unusual death.

Secondly, if someone can learn from the accident and can prevent it from happening again, then your death helped save others' lives and that can be considered a sacrifice, whether you willingly invited it or not.

I'm not saying that's the correct answer; just speculating.

There is the jist of it and to elaborate. Often in such a business you are going out there knowing there are all sorts of design issues that in a perfect world would be worked out absolutely safe environments. But in the war business you go into harms way with the knowledge that your equipment has defects that will possibly kill you. But you go forward knowing/hoping that if it does your comrades will use that to prevent recurrence. Thus you can be eager to face great risk in performing your duties even when not in the face of the enemy.

[Nuc]

To all:


There has been discussion in the past here in these forums concerning the loss of the USS Scorpion (SSN-589).

Thanks for providing this information. I saw Mr. Rule's conclusions in a letter to Proceedings a while back. He seems to be working hard to get out the information.

http://www.subsim.com/radioroom/showpost.php?p=1136478&postcount=24

[RadioStriker]

I'm a navy vet--kiddy cruised from 1965 to '68. Black Shoe, but not a pig boater. I am interested in the bad new event called a hot run.

I worked--post Nav--with a guy who was in the diesel boats about the time I was in. He told a scary story about a hot run in the forward room.

The torpedo lit off and filled the room with nasty exhaust. Per sched they dogged the door and left the guys there to deal with there maker. Sad story about somebody banging to get out and then dropping quiet. Eternal Father Strong to Save...

Skipper surfaced mo skosh and the opened the torpedo room deck hatch and the dogged door mentioned above. My pal said the gasses blew aft and knocked him out. I think all the squids survived. He thought he was effected much later by CO. I mean carbon monoxide instead the captain. This was told to me in the 1980s? He was kind of ditsy.

Now the question. I read of hot run in the wwii stories, and no mention is made of a gas problem. Who is ****ting us, my old pal, or the people who write the stuff?

[rein1705]

My grandpa says that the torpedoes let out a terrible steam or gas when that happened. He served aboard a Balao near the end of WWII and on into the 50's.

[Rip]

Not sure about the WW2 ones but modern torpedoes use a fuel called Otto Fuel (http://en.wikipedia.org/wiki/Otto_fuel_II) that when the torpedo runs emits Hydrogen cyanide (http://en.wikipedia.org/wiki/Hydrogen_cyanide) very nasty stuff indeed.

Rip

[Rockin Robbins]

Not to come off as a jerkass and go too far off topic but how is dying in an accident a sacrifice? I agree that if things are learnt from it it's 'not dying in vain' but when saying 'sacrifice' I think 'dying knowingly and willingly for a reason or cause'.
I apologize if I offended anyone but that's just me thinking aloud: I'm Polish so these questions are rather close to me lately after Smolensk.

I think as soon as you join the military you are sacrificing your right to live, if your superiors deem it necessary, in favor of obeying orders that can result in your death. Whether you live or die, you have made that sacrifice.

[DaveyJ576]

Gotta love the Navy. I have been busy as hell lately at work. Reserve drill weekend, command inspection, renovation conference, etc.

Anyway, the mystery concerning the placement of the Salmon/Sargo class deck torpedo stowage tubes has finally been solved! I picked the brain of the eminent author and historian Jim Christley and sent him digging into his files. He found that the stowage tubes were stacked vertically, two each on either side of the conning tower and the deck gun mount inside the superstructure. They were sited just aft of the large deck hatches that covered the liberty boats. Check out this graphic:


http://i857.photobucket.com/albums/ab132/DaveyJ576/OutboardandDeck.jpg?t=1285361884

To unload the tubes, both boats were removed and placed temporarily in the water alongside. The torpedoes were then extracted from the tubes and into the space left by the boats. They were then hauled up to the deck by the same davit used to move the boats and placed onto the raised torpedo loading skid just forward of the boat hatches. They were then lowered into the torpedo room one by one in the normal fashion.

I had suspected that this was the case. It was the only arrangement that made sense and that would enable the tubes to fit into the superstructure.

This is a perfect example of pre-war submarine design philosophy. A lot of novel features were incorporated into the boats during the 30's that were great for peacetime cruising, but turned out to be near useless liabilities when the shooting started. The boat CO's discovered pretty quickly that these tubes were not going to provide the benefit they were intended for and they were one of the first things to go as the boats were overhauled.

[LukeFF]

Nice find there!

I do recall reading about the liberty boat launches being done away with fairly quickly once the war began.

[DaveyJ576]

I have spent the last week and a half revising the Wikipedia page on the Gato class submarines. The original was incomplete, misleading, and in some cases completely wrong. I think it will stand the test now. Take a look when you have the chance:

http://en.wikipedia.org/wiki/Gato_class_submarine

Enjoy!

[Ducimus]

I have spent the last week and a half revising the Wikipedia page on the Gato class submarines. The original was incomplete, misleading, and in some cases completely wrong. I think it will stand the test now. Take a look when you have the chance:

http://en.wikipedia.org/wiki/Gato_class_submarine

Enjoy!

Great write up!

[NorthBeach]

I have spent the last week and a half revising the Wikipedia page on the Gato class submarines. The original was incomplete, misleading, and in some cases completely wrong. I think it will stand the test now. Take a look when you have the chance:

http://en.wikipedia.org/wiki/Gato_class_submarine

Enjoy!


Well done! :salute:

[rokket]

Davey, brilliant stuff...taxing and stretching here maybe: What about Mk 6 exploders and their impellers? Yes, I saw some stuff waaay back in the thread, but I'm interested in the recent "hot run" post...if a fish were sticking out the tube, stuck, and the impeller was spinning, it seems these revolutions would start to arm it...unless there was a governor that only counted revolutions at a torp's normal speed...??? Thanks

[DaveyJ576]

Davey, brilliant stuff...taxing and stretching here maybe: What about Mk 6 exploders and their impellers? Yes, I saw some stuff waaay back in the thread, but I'm interested in the recent "hot run" post...if a fish were sticking out the tube, stuck, and the impeller was spinning, it seems these revolutions would start to arm it...unless there was a governor that only counted revolutions at a torp's normal speed...??? Thanks

The Mk 6 exploder is actually electrically powered. On the bottom of the exploder mechanism (which actually forms the bottom of the warhead itself) a channel is cut into the body which directs a flow of water over an impeller. The spinning of this impeller drives a small generator and this is what provides the power. Two different safety mechanisms prevent the exploder from firing the warhead until a certain point of travel (I believe it is 400 yards, but don't quote me on that right now)

So in your scenario (which has happened by the way) the fish is stuck part way out of the tube, which means it has only traveled about 10 feet. The exploder isn't yet armed. The impeller and the associated gear train is set up in such a way that only the force of water moving at the weapon's design speed (31-46 knots) would be sufficient to rotate the impeller and arm the torpedo. The speed of the submarine through the water (< 8 knots) would not be enough to rotate the impeller gear train.

Don't get me wrong though. This is a very dangerous situation. The only real solution is to refire the tube and hope the weapon is ejected. If it is in an aft tube, the boat would probably be running at a full bell to accelerate the separation of the boat and the weapon. If in a forward tube, it would be backing down for the same effect.

The following link has a lot of good info on the exploder operation:

http://www.hnsa.org/doc/torpedo/index.htm

[kraznyi_oktjabr]

I have question on following text from U.S.S. BAYA (SS-318) FOURTH WAR PATROL REPORT27 April 1945 at 0235:
"APR contact on 305 mcs., 200 TRF, strength 5. This contact was followed by jamming which effectively blacked both united of APR and completely blacked SD."

Could someone explain what are APR, mcs, TRF and this "strength 5"? Also what kind of jamming gear Japanese would be using?

EDIT: Okay I missed section where APR was mentioned to be somekind of radio, my bad. Would still like to hear more about it.

Thanks!
Tim

[Platapus]

I have a question that has been buggin me for a while.

When watching some of my WWII sub movies, there was a command given that I would like someone to explain to me

"Put a bubble in Safety"

Now the Safety tank was a tank with the same displacement as the conning tower. Its primary use was to compensate for a flooded conning tower in case of an emergency.

As such the Safety Tank was normally kept full of water as it would be common practice to keep the conning tower empty of water. :know:

The Safety Tank could be blown in case emergency buoyancy was needed.

"Put a bubble in Safety"

Is this strictly Hollywood BS?

If not, why would you put a bubble in safety and when would you normally do it?

To this landlubber's tiny mind, putting a bubble in safety means blowing the safety just a tiny bit so that there is mostly water with a small amount of air on the top.... a... well... bubble as it were. Since bubbles can compress is this bubble necessary for safety reasons??

Inquiring minds want to know. :88)

[Platapus]

Could someone explain what are APR, mcs, TRF and this "strength 5"? Also what kind of jamming gear Japanese would be using?



TRF Tuned Radio Frequency http://en.wikipedia.org/wiki/Tuned_radio_frequency_receiver A type of multi frequency radio receiver. I am not sure what the "200" signifies. I can guess that it is referring to Ohms. But I am just guessing.

MCS - Since MC stands for megacycle, I can guess that MCS means megacycles http://www.acronymfinder.com/Megacycle-%28now-megahertz%29-%28MC%29.html These days we use Megaherz (MHZ)

Strength 5 comes from a code used to evaluate the signal strength of voice communication. It is different from the RST code used for Morse Code signals.

When evaluating a voice signal one may use the term "five by five" meaning 5 strength (highest) and 5 clarity (highest). In this case only the strength of the signal was given (5) meaning a very strong signal.

[DaveyJ576]

I have question on following text from U.S.S. BAYA (SS-318) FOURTH WAR PATROL REPORT27 April 1945 at 0235:
"APR contact on 305 mcs., 200 TRF, strength 5. This contact was followed by jamming which effectively blacked both united of APR and completely blacked SD."

Could someone explain what are APR, mcs, TRF and this "strength 5"? Also what kind of jamming gear Japanese would be using?

EDIT: Okay I missed section where APR was mentioned to be somekind of radio, my bad. Would still like to hear more about it.

Thanks!
Tim


Platapus beat me to a reply with some good info. To add to that, starting in late 1944, some submarines were equipped with the APR series radar detection equipment. It consisted of both a receiver and a pulse analyzer. It served mostly as an early warning set, basically to let the crew know that there was an enemy radar set out there working. Due to the limitations of the gear, getting a bearing was problematic. Later refinements in antenna placement allowed a rough bearing to be obtained, but this often required turning the entire boat.

I would be very surprised to learn that the IJN was using any sort of active jamming gear. This technology was in its infancy and even the USN did not possess it at this point. Probably what the Baya was seeing was unintentional. A Japanese radar operating on a frequency that was close to that of the SD (especially if it was more powerful) would cause interference on the screen and muck up the reception, essentially "jamming" it.

[DaveyJ576]

Now the Safety tank was a tank with the same displacement as the conning tower. Its primary use was to compensate for a flooded conning tower in case of an emergency.

As such the Safety Tank was normally kept full of water as it would be common practice to keep the conning tower empty of water. :know:

The Safety Tank could be blown in case emergency buoyancy was needed.

"Put a bubble in Safety"

Is this strictly Hollywood BS?


Actually, no it is not BS. I think you are getting tripped up on jargon. "Put a bubble in Safety" actually means partially blowing the tank, emptying part of the tank in an effort to restore positive buoyancy, possibly as a result of battle damage related flooding in another part of the boat. As you noted, the safety tank is normally kept flooded at all times, and would only be emptied to compensate for flooding, usually of the conning tower, but it could be used in any flooding casualty. In this function, it has almost the exact opposite use as the negative tank, which is meant to provided negative buoyancy during the first part of the dive, to get the boat down faster. Once the boat is under, the negative tank is "blown to the mark". This is a predetermined point at which, when emptied to this mark, neutral or a slightly positive buoyancy will be reestablished. The "mark" changes constantly as fuel is used, garbage is thrown overboard, ammo is used up, etc.

Putting a "bubble" in safety would only be done if the boat was having difficulty maintaining neutral or positive buoyancy due to leaks or flooding.

[Platapus]

Ah, so putting a bubble in safety is, in fact, adding a little bit more positive buoyancy to the boat?

Would a bubble in safety be put in times where there is no damage?

If the trim analysis for a specific dive were to be "Heavy overall and all right fore and aft", would a remedy be putting a bubble in safety to establish the trim?

(I love this thread, so much to learn, so many willing to teach)

[Nuc]

If the trim analysis for a specific dive were to be "Heavy overall and all right fore and aft", would a remedy be putting a bubble in safety to establish the trim?

No. Safety, as the name implies, was use only in emergency. Here you would probably pump from the trim tanks to sea.

[kraznyi_oktjabr]

Platabus and Dave, thank you very much for your answers!

[LukeFF]

I have spent the last week and a half revising the Wikipedia page on the Gato class submarines. The original was incomplete, misleading, and in some cases completely wrong. I think it will stand the test now. Take a look when you have the chance:

http://en.wikipedia.org/wiki/Gato_class_submarine

Enjoy!

Well done!