That's interesting. I find this somewhat surprising considering that there's the bow planes, torpedo tube doors, hydraulics and such all in the ballast tanks. I would have thought that they would need at least eye-balling quite often just for the sake of "looking under the hood and checking the oil". How easy do you think it would be to have ventral doors on the ballast tanks so that they are water free when the sub is surfaced and docked? Is it possible?

Nah, there are operational checks to be done sure, but most of the testing can be done remotely. Hydraulic? Hydrostatic testing, Limit switches? There are multiple redundancies. There are no real operational issues. The inspections are saved for when you have to drydock. If something SERIOUS happened and BROKE one of these neccessary devices then you go into the dock, and then you take care of as much as you can while you are in there.

MBT on most modern NUKE boats are open to the sea. This allows for faster filling and simplier operation. You go out and open the MBT vents and you sink. You KNOW they are going to flood when you open the vents.

A diesel boat may have MBT bottom seacocks, but this is because the MBT may do double duty as a fuel tank. I'll bet you that any non-fuel capbble MBT is open to sea at the bottom with no seacock to seal the tank at the bottom.

Why no hatches on top you ask? They may be damaged and leak. They could be opened by the shock of a depth charge. They may make flow noise around the hinge or around the peremeter of the hatch. There are all kinds of problems that I see if you put an access panel in the top of the MBT's. I see no positives in it at all. Would YOU want your MBT's to not hold air due to an undersea collision like the San Fransisco? If there are no openings, then there is nothing to leak air in the event of a problem.

Hm... that's interesting as well. Did the San Francisco's tanks still hold air after it's crash? That ballast tank looked like a floating disaster. http://www.maritimequest.com/in_the_...sco_damage.jpg

What intriguing is that all the design reviews and research recommendations are urging to push more and more stuff into the bow and aft. The Defense Science Task Force recommended "bomb-bay" approaches, and the USN Darpa is asking for "shaftless propulsion" and "external weapons", even the Virginia Block III is proposing ditching the 12 verticle tubes for 2 large SSGN type tubes in the bow, so it seems that it will be unavoidable for more bow/ballast tank access as a must, unless all the research will just end up whistling dixie...

I heard Russians use seacocks on MBTs too. With open MTB, the air inside is at pressure of bottom hole depth, which is about 3 atmospheres for nuke.
Russians blow, then close the seacocks, then open vents. That reduces pressure inside MBTs to 1 atmosphere. So actual weight of the air insied is lowered 3 times, which makes flooding faster.

As for the picture of crashed LA .. LA uses sonar dome in front of the pressure hull, which is covered by fiberglass to smooth the shape. Pressure hull starts at the green wall (IMHo). While it's bended, I'd say it holded.
First wents are actually about 2 meters in front of the active sonar warning reciever, which is the small black thingy right next to the first guy above.

I have better pictures, but I am unable to post them.

Anyway, there are 3 forward MBT's on a 688. They are divided into further divided into two tanks. One port, One starboard.

Think of them like this:

<bow>
1a/1b
2a/2b
3a/3b

You have a fibreglass done that covers the sonar sphere. (Quick qual question: How many watertight compartments are there on a 688? Anyone? Anyone? FOUR. They are the sonar sphere, the forward compartment, the reactor compartment, and the aft compartment)

Anway, the 1a was voided to sea and useless. 1b & 2a were leaking badly. You had to keep pumping air into them and it was leaking out about as fast as you could pump it in there.

That left 2b, 3a &b to support the mass of the submarine at the bow. The sonar sphere (that forward most watertight compartment) was flooded due to the damage.

That they survived is a testimate to the training they had and how well we build boats. There was also some luck involved of course

Here is something I think you might like, it is the account from the DOOW on the San Fran:
February 12, 2005 - DOOW Account


To say the world went to shyte in a hand basket would be an understatement. I would put it closer to a nightmare that becomes reality.

The seamount that is a large part of the discussion the last 2 weeks is un-named. The charts we carried onboard were up to date as far as we cantell. No modern geographic data for this area was available to us onboard as it is a remote area not often traveled by the Navy. We have one of the BEST ANav's in the fleet onboard, a true quartergasket that takes pride in his job. We have RLGN's onboard, when they are running, they are accurate as hell for our position, they also drive Tomahawks.

We knew where we were. All of my depth gauges and digital read the same depths as we changed depth to our SOE depth for flank. I can't discuss alot, because I'm still a participent of at least 2 investigations....LOL.

As for the actual grounding, I can tell you that it was fortunate that myself and the Chief of the Watch were blessed by somebody. I was standing up, changing the expected soundings for a new depth on the chart (yes, we had just moved into deeper water) leaning against the ship's control panel with a hand grip, and the COW was leaning down to call the COB on the MJ.

The next thing to cross my mind was why am I pushing myself off of the SCP and where the hell the air rupture in the control room come from? I didn't know it, but I did a greater than 3g spiderman against the panel, punched a palm through the only plexiglass gauge on the SCP and had my leg crushed by the DOOW chair that I had just unbuckled from. The DOOW chair was broken loose by the QMOW flying more than 15 feet into it and smashing my leg against a hydraulic valve and the SCP. I don't remember freeing myself from it. If I had been buckled in, I don't think I would be writing this.






I would say that about 80% of the crew was injured in some way, but do not know the number. We grounded in the middle of a meal hour, just after field day, so most of the crew was up. Once we got the boat on the surface and semi-stable with the blower running the rest of the ship conditions started sinking in to our minds.

:har: :har: You guys said "sea-cocks":har:

Of course, what else would you find in you sea-socks!:yeah:

I meant valves if it's not clear.
If it's just funny, it's ok with me. :arrgh!:

You were clear Sid. Just some American humor where anything sounding remotely naughty makes us laugh.:salute:

You call this 'remotely' ? :rotfl:

Yep! I used to like the Beevis and butthead cartoon where they did this type of humor often.:)

Truely a testimate to the sturdiness of the boats. That's good engineering...:o :cool:

Random question for the RL submariners.

Do submarines have regular washer and dryers on board for clothe washing or are they specially made units for "ultraquiet" operation?

I just wondered since I can hear my own washer across my apartment with all doors closed.:hmmm:

On a 688, there is ONE washer, and ONE dryer. They are stacked one on top of the other near AMR in the lower level. They can handle a LOT of clothes. They are rather efficient little machines.

As for beinh special built? Well, they are small but not overly quiet. They ARE sound isolation mounted BUT, if you need to be quiet you do not use them.

People used to wonder WHY an experinced bubblehead would go to sea with 30 pairs of t-shirts, underwear and socks. You can go for a month without having to do laundry.

Patrol Quiet you have to ask permission from the OOD (or Capt) through the Chief of the Watch.

Ultra Quiet, no wash, no dry. Better have extra's.

Oh, and if the fresh water evaporator breaks down (and it would), no wash. (or shower for that matter).