One Torpedo, One Ship?

[Bubblehead1980]

I remember watching a 5 part series via youtube a week or so ago about U boats, very good show.I remember one "Ace" was said to use one torpedo for one ship....were German torpedos the powerful? Would this work in U boat game? Im a fleetboat guy so U boat stuff is still mostly an unknown arena.Not starting the discussion but hoping DRM is dropped so I will buy SH 5

[Deep Dive]

If i remember well this was the moto of "Silent" Otto Kretschmer
Torpedoes were generally powerful enough to bring most ships down in most cases
There were many "duds" of course especially in the first years
Both Americans and Germans experienced various similar problems

[Sailor Steve]

American policy was to fire three torpedoes at most targets. Of course they carried 24 torpedoes, so they were ready for that.

Read Uboat.net's accounts of how many ships were hit by one German torpedoe and sailed away to tell about it. Also there are many accounts of one torpedo stopping the ship, and the u-boat giving it a 'coup-de-gras' several hours later. Or sank it with the deck gun. Or tried that and then delivered a second eel. And sometimes a third.

'One ship, one torpedo' makes a nice saying, but the German torpedoes didn't fare any better than the American ones did.

[Galanti]

It's an ironclad rule on U-56 right now in my Operation Monsun career, but only because she only carries five of them. I go for magnetic keel shots as much as possible.

In my RFB campaign, Christ, I'll empty the whole bow at one little Maru to compensate for deep-runners, duds and my general ineptness.

I think Steve's right, plenty of ships went down to one fish, but it was by no means the majority.

On the other hand, we'll never know how many went down to multiple fish where just one would have sufficed.

[Jimbuna]

http://www.modelshipmaster.com/products/submarines/U-99.htm



In the first four patrols of the U-99, Kretschmer started striking convoys at night on the surface, taking down merchant ships with highly accurate shots, using only one torpedo per target ship in order to save ammunition, and the quote "One torpedo ... one ship" is attributed to Kretschmer from around this time.

[Bubblehead1980]

Thanks for the replies.One thing I hope is possible in SH 5 is to be able to get inside the convoys as real U boats did.I never played SH 3, was this possible?

[ReFaN]

Thanks for the replies.One thing I hope is possible in SH 5 is to be able to get inside the convoys as real U boats did.I never played SH 3, was this possible?

done it once or twice, but after you hit something you would probably die very quick from the Merchants guns :P

[Jimbuna]

Thanks for the replies.One thing I hope is possible in SH 5 is to be able to get inside the convoys as real U boats did.I never played SH 3, was this possible?

Under ideal nightime conditions (certainly in GWX3.0 anyway) it was possible, but because of the close proximity of the merchants and escorts it was best practice to dive deep as soon as you emptied your tubes.

[Méo]

Under ideal nightime conditions (certainly in GWX3.0 anyway) it was possible, but because of the close proximity of the merchants and escorts it was best practice to dive deep as soon as you emptied your tubes.

Maybe, but if we are back to the ''one torpedo, one ship'' seems to me like this motto was almost impossible to achieve in GWX 3.0. :hmmm:

[TarJak]

Maybe, but if we are back to the ''one torpedo, one ship'' seems to me like this motto was almost impossible to achieve in GWX 3.0. :hmmm:
Not impossible, just much harder than stock. A shot to the bow compartment of most targets takes them out after short while or a keel shot under the engine room or fuel bunker usually sinks them in one go.

Personally my motto is "Anything worth shooting is worth shooting twice." the results from this practise I find more than satisfactory.

[Dissaray]

I've droped ships with a single eel a number of times useing GWX3. It isn't a sure thing thoguh, and high seas after the hit certanly help. More often than not I find my slef puting two into targets befor they go down, the larger ones any way.

The trick is to aim low and try to bust the keel or put a hole fully below the waterline. But it is generaly not a good idea to get all stingy with the ammo when things get thick.

[Platapus]

I remember watching a 5 part series via youtube a week or so ago about U boats, very good show.I remember one "Ace" was said to use one torpedo for one ship....were German torpedos the powerful?

1943
Mark 14 torpedo (USN) 643 Pounds/292Kg of Torpex

G7a (German) 661 Pounds/300Kg Hexanite

Torpex consists of 42% RDX, 40% TNT and 18% Aluminum Powder

Hexanite or what the Germans called "SW39a" was 50% TNT, 10% Hexinit, 5% ammonium nitrate, and 35% aluminium powder.

Comparing explosives can be difficult. The term "more powerful" can be misleading. The term "Brisance" is used as a measure of how fast an explosive can reach its maximum pressure.

Explosives with lower Brisance well tend to push an object away (very low Brisance explosives can be used as a propellant). Explosives with a higher Brisance will tend to shatter an object.

Explosives with a lower Brisance will tend to have a longer explosive pulse (the duration of highest pressure). Explosives with a higher Brisance will tend to have a shorter explosive pulse.

So when trying to sink a ship with a torpedo, do you want explosives with a higher or a lower Brisance?

The answer is yes. Because torpedoes have the special advantage of being used underwater, the water can serve as what is called a Tamper. The inertia of water contains the explosive wave therefore increasing the duration (and incidentally focusing) the explosive pulse. What you want is an explosive that has both the effects of a higher Brisance (for the speed to get to maximum pressure) and the effects of a lower Brisance (for the longer duration of that maximum pressure). The trouble is that it is difficult to have both.......unless you are underwater. :up:

The addition of Aluminum Powder to an explosive is an effective way to add the effect of a lower Brisance explosive to the existing higher Brisance.

As we learned in EOD school, a little pinch of powdered Aluminum is always a good thing.

Ok "professor" Platapus, you have used all the big impressive words, what the hell does all this mean?

Simply put, the ability to penetrate the hull of a ship is more affected by the higher Brisance of an explosive. But we don't need to penetrate the hull of a ship to sink it, all we need to do is separate the hull plates (think Titanic). This is more easily accomplished by using an explosive with a longer explosive pulse.

The Germans, in an attempt to economize, developed a combination explosive (Hexanite or SW39a) that while it had a lower total explosive power than Torpex (lower Brisance), the higher proportion of Aluminum powder turned that lower power explosive compound into a more effective explosive compound. Effective for this one purpose, that is.

This is why it is difficult to compare explosives. It depends on the compound and its intended use. This is why we don't just put C-4 in to every piece of ordnance. C-4 is good at what it does, but other explosive compounds are good at what they do. There is no universal "best" explosive.

So to reference back to the original question, yes the German torpedoes using SW39a were more effective at comprimising the integrity of the hull plates of merchant ships, despite being "less powerful" than US torpedoes using Torpex.

If your intended target is an armoured hull of a military ship, the story changes. To penetrate armour (as opposed to spalding the armour) you will need a higher Brisance explosive.

In this case, the US torpedoes with Torpex woudl be more effective at compromising the integrity of the armoured hull of a military ship..... assuming the damned Mark 14/Mark 6 even functioned.. but that is another story.

Probably more than you wanted to know. But when discussing the effectiveness of explosives, some background needs to be understood.

And we did not even touch on the secondary explosive effects or the depth of the explosive pulse. :doh:

[Sailor Steve]

If your intended target is an armoured hull of a military ship, the story changes. To penetrate armour (as opposed to spalding the armour) you will need a higher Brisance explosive.

In this case, the US torpedoes with Torpex woudl be more effective at compromising the integrity of the armoured hull of a military ship..... assuming the damned Mark 14/Mark 6 even functioned.. but that is another story.
This is where I disagree. It's my understanding (I've read some actual sources but don't have them handy right now, so "it's my understanding" is as far as I will commit right now) that tests were done during the First World War that concluded that hardened armor isn't really more resistant to a torpedo hit than mild steel. The armor was designed to resist 'point hit's from a shell coming in at supersonic speeds. What did help a little was the fact that the armor was much thicker than the usual 1/4-to-1/2 inch steel plates found on destroyers up through merchants, but the very weight of the armor meant that it couldn't be very wide, usually ending just a few feet below the waterline. This left the lower hull exposed, and toward the end of World War 1 the British started experimenting with TDS (Torpedo Defense Systems). These usually consisted of a 'bulge' of mild steel which was filled with some liquid, allowing the torpedo to rupture the bulge and not reach the hull. The magnetic detonator was originally created to counter that, since the bulge itself couldn't be made to wrap around the bottom of the ship.
http://www.navweaps.com/index_tech/tech-047.htm
http://en.wikipedia.org/wiki/Anti-torpedo_bulge

[Hartmann]

In shV it´s not a problem, you can always use the increase explossive power hability of the weapons officer.

perhaps firing a modified torpedo with doble amount of explossive or two tied with duct tape...:hmmm:

[longam]

As long as their shields are down, one torpedo should do it...oops wait I just watched star trek new movie.

[ERPP8]

It all depends.
Factors like ship size, depth, place of impact and now torpedoes that use their unspent fuel as extra explosives.

[Frederf]

Absolutely delightful bit of knowledge, Platypus!

It really takes only one look at a YouTube video of a real MK14 hitting home to see how powerful they really were. The graphics in Silent Hunter don't really do justice to the violence of it. An un-compartmentalized merchant ship without some exotic cargo (cork, etc.) hit in a reasonable place... one should do in the majority of cases. Multiple shots have mostly to do with problems in torpedo reliability, errors in aiming, and maneuvers by the enemy.

Every single (merchant) ship I've hit with a single torpedo in GWX has sunk without fail.

[V.C. Sniper]

Yeah, that one merchant that was hit by a torpex equiped MK14/MK18 looked like it literally disintegrated into a cloud of black particles.

[Kaleun_Endrass]

@Frederf, @V.C. Sniper:
Does one of you have a youtube link for the MK14 torpedoe explosion? Can find torpedo tests on decommissioned destroyers only... Thanks.

[Arclight]

Platapus, Steve (Stewie :O:): would it be correct to assume that an explosive with a lower Brisance is more effective when it comes to keel shots, i.e. lifting the ship out of the water in order to "break it's back"? :06:

[Snow White Sorrow]

done it once or twice, but after you hit something you would probably die very quick from the Merchants guns :P

I love to slip in at night, stormy seas, or bad weather and fire torpedoes literally in all directions at once.

In those conditions (<600 yards visibility) the game does not allow auto target tracking so its pure manual TDC work, and draw your own paper plot.

Skulk around, plot convoy formation (hope they don't zigzag or you'll likely get rammed without warning), fire on bearing beyond visual range.

[Frederf]

@Frederf, @V.C. Sniper:
Does one of you have a youtube link for the MK14 torpedoe explosion? Can find torpedo tests on decommissioned destroyers only... Thanks.

If you're watching this video: http://www.youtube.com/watch?v=vYAWrkvyYdc I think that isn't a MK14. I think that's a much more modern (and powerful) torpedo. I could be wrong but that's my impression.

Try this one at 1:39 http://www.youtube.com/watch?v=-6V56xzp5Jw
4:01 and 6:21 http://www.youtube.com/watch?v=V3rhxYq2nNI

[Sailor Steve]

Oh yeah. Saw that one years ago. Not a Mk 14 at all. At the very least a Mk 48 'homer'.

[ryanglavin]

In My GWX 3.0 experience, hitting everything up to The Whale Factory ship will sink with a single hit to the bow, albeit if not after 45minutes-3 hours.
IF you hit tankers in the bow, they disintegrate.

[tater]

I went through that u-boat database when this subject came up before, and found that the number of fish required to sink ships of similar sizes was actually MORE for german torpedoes in most cases compared to the Mark 14. ( I also went through every single US submarine torpedo attack of the war and made a database of them).

It was not at all the answer I expected, but it's what the reports/narratives spit out if you start counting up 1 hit sinkings vs 2 or more.

The guy I was arguing with, BTW, counted ships that made it back to port, but were written off as losses a "sinking" to try and bolster his 1 hit, 1 sinking notions. Not so, writing a hull off is an economic decision, allies were making so many hulls, repair cost more than scrapping (just like remodeling costs are more [per ft^2 than new builds for houses).

Some links:
Below link I compared warship attacks, virtually no difference in numbers of fish to sink between u-boat and fleet boat attacks that matters.
http://www.subsim.com/radioroom/showpost.php?p=994372&postcount=53


Below, I compared Hog Islander sized targets, and the US sinking rate with only 1 hit was 88%.

http://www.subsim.com/radioroom/showpost.php?p=994741&postcount=67

The German rate (from u-boat.net) to ALL attacks on Hog Islanders was 94% successfully attacked were sunk. Since it gives no fish count, that 6% difference accounts for attacks with 2 fish, AND deck guns added in. Even if you assume none were every attacked or hit with more than 1 fish, and none were ever attacked with the DG, that difference is well within chance (or sea state differences between the N Atlantic and PTO).

I later went through all the narratives for the hog islander attacks and figured out the hits per sinking:
http://www.subsim.com/radioroom/showpost.php?p=994866&postcount=74

ONly 50% sank with 1 hit compared to 88% of jap ships of similar tonnage (I actually counted ships larger than the hog islanders, too, since most of the similar jap ships were slightly larger than that).

For late war, I checked Liberty Ship stats, I read every Liberty Ship attack u-boat narrative and:
Liberty (~7k t) vs U-Boats, 18.18% sunk after hitting with 1 torp (1944)
7k t jap vs Fleet Boats, 79.17% sunk after hitting with 1 torp. (entire war)

[java`s revenge]

If you're watching this video: http://www.youtube.com/watch?v=vYAWrkvyYdc I think that isn't a MK14. I think that's a much more modern (and powerful) torpedo. I could be wrong but that's my impression.

Try this one at 1:39 http://www.youtube.com/watch?v=-6V56xzp5Jw
4:01 and 6:21 http://www.youtube.com/watch?v=V3rhxYq2nNI

Many thanks for the second link, very interesting :yeah:

[utops]

Hello.
I just want add some tip for GWX eel settings.
IF ship is in hurry, place eel near bow
- Thats how to turn surface vessel in to submarine,works in most cases...
Warships can resist that trick.... i don`t know for sure,because warships in GWX is real rare thing to encounter.

[Platapus]

Platapus, Steve (Stewie :O:): would it be correct to assume that an explosive with a lower Brisance is more effective when it comes to keel shots, i.e. lifting the ship out of the water in order to "break it's back"? :06:


Yes

What you would want in order to move all that water out of the way is a longer explosive pulse. This is where the Aluminum powder comes in (it "burns" longer). This combined with a lower Brisance explosive would tend to "propel" the water out. The explosive wave of a higher Brisance explosive will tend to be absorbed by the inertia of the water. This one of the reasons why underwater demolitions often involves different explosive compounds than above water demolitions.

[Platapus]

This is where I disagree. It's my understanding (I've read some actual sources but don't have them handy right now, so "it's my understanding" is as far as I will commit right now) that tests were done during the First World War that concluded that hardened armor isn't really more resistant to a torpedo hit than mild steel. The armor was designed to resist 'point hit's from a shell coming in at supersonic speeds. What did help a little was the fact that the armor was much thicker than the usual 1/4-to-1/2 inch steel plates found on destroyers up through merchants, but the very weight of the armor meant that it couldn't be very wide, usually ending just a few feet below the waterline. This left the lower hull exposed, and toward the end of World War 1 the British started experimenting with TDS (Torpedo Defense Systems). These usually consisted of a 'bulge' of mild steel which was filled with some liquid, allowing the torpedo to rupture the bulge and not reach the hull. The magnetic detonator was originally created to counter that, since the bulge itself couldn't be made to wrap around the bottom of the ship.
http://www.navweaps.com/index_tech/tech-047.htm
http://en.wikipedia.org/wiki/Anti-torpedo_bulge

Absolutely! The science of designing armour plating is a most complex topic. Similarly to explosives (in that there is no best for all purposes) there is no "best" armour composition. What pretty much everyone learned during WWI is that it is not simply a matter of finding the "strongest" metal compositions and then increasing the thickness. :nope:

Armour plating needs to be designed to resist a particular type of attack.

Against hardened armour piercing ordnance, thicker more dense armour is good.

Against explosives, less dense armour that can flex is good.

This is actually a criminally oversimplified explanation of an incredibly complex topic of armour design and construction.

Actually armour is made up of layers with different metals as distinct layers with other layers made of different metal compounds. It is an interesting topic.

I am afraid I am more familiar with blowing stuff up than designing stuff to resist being blown up. But excellent points Steve. :salute:

One can't discuss the effectiveness of torpedoes without taking into effect the hull/armour compositions.

[Platapus]

Hello.
I just want add some tip for GWX eel settings.
IF ship is in hurry, place eel near bow
- Thats how to turn surface vessel in to submarine,works in most cases...
Warships can resist that trick.... i don`t know for sure,because warships in GWX is real rare thing to encounter.


Is that because the impetus of the ship's movement will force more water into the ship?

Does GWX model that?

[Frederf]

I've heard that an "under the keel" shot was good for causing many leaks at riveted panel borders all over the ship which were hard to repair before maybe a long duration sinking. Is this true?

[Hartmann]

well, usually the explossion blast broke the keel and the ship splits in two after the up and down movement.:yep:

[Bubblehead1980]

when keel shots were made, they worked well.Problem was with US fish most of the time their magnetic detonators were active they were faulty and detonated prematurely and they also ran 10-12 feet deep on average for a long time.However, they figured out they were running deep and fixed that and some skippers made keel shots with great effect.Magnetic detonators remained terribly unreliable and were finally deactivated, going back to contact only.

The game(SH 4) reflects RL pretty well in sense a large merchant that may take 3 or 4 solid hits with contact detonators to sink can be taken out with 1 or 2 keel shots.As far as German fish go , I know they had problems with their magnetic detonators, not sure if they ran deep.Many times 1 fish blowing up 5 feet below the keel amidships was/is enough to sink it.

[Rockin Robbins]

I remember watching a 5 part series via youtube a week or so ago about U boats, very good show.I remember one "Ace" was said to use one torpedo for one ship....were German torpedos the powerful? Would this work in U boat game? Im a fleetboat guy so U boat stuff is still mostly an unknown arena.Not starting the discussion but hoping DRM is dropped so I will buy SH 5

That's funny, both Eugene Fluckey and Dick O'Kane said the same thing. That didn't mean it really worked that way all the time. American and German torpedoes were comparable in explosive power. They should be since the American torpedo was a copy of the German ones, faults and all.

[frau kaleun]

well, usually the explossion blast broke the keel and the ship splits in two after the up and down movement.:yep:

I'm gonna assume that's a 'yes' on major leakage.

:O:

[Platapus]

Concerning the effectiveness of the under the keel shot:

In a letter from BuShips chief, Vice Admiral E.L. Cochrane to Blandy [BurOrd chief] regarding the most effective depth at which to achieve torpedo hits, Cochrane took the opportunity to comment on the supposed advantage magnetic influence explosions beneath a ship's keel:

"Except for ships fitted with torpedo protections systems, the Bureau [BuShips] is unable to see any great advantage in obtaining non-contact hits under the bottom" *

The Bureau of Ships housed the Navy's foremost ship designers and naval architects. The BuShips' engineers studied torpedo damage on scores of ships, including those of foreign navies. For them to conclude that the MK. 6 magnetic feature offered no advantage over contact exploders (except on large capital ships) was a devastating revelation to BuOrd, who cited the effect of magnetic influence explosions in defense of charges levied against the MK 6 by the operational submariners.

Newpower, A (2006) Iron Men and Tin Fish London: Praeger Security International p. 147

* Citation for Cochrane quote:

Letter from Vice Admiral E. L. Cochrane to Blandy, 26 March 1943, RG 38, Correspondence of the Office of the Chief of Naval Operations, National Archives

[Rockin Robbins]

In shV it´s not a problem, you can always use the increase explossive power hability of the weapons officer.

perhaps firing a modified torpedo with doble amount of explossive or two tied with duct tape...:hmmm:

There you go! Use the arcade game feature! What part of the word "simulation" got lost here?

[Sailor Steve]

I don't know. The duct-tape idea seems like a good one. But only if we can see the torpedo crew actually doing it.
:rotfl2: