Holes in the pressure hull

[Deathblow]

I'm trying to figure out all the holes that a submarine has that have to penetrate the pressure hull. Don't ask me why, I just have to know because I'm an obessive-compulsive type ok? I just need to know! :oops: :lol:

So far I've got (staring from front to back)

1. Torpedo tubes
2. Cable relay from the bow sonar array
3. Forward weapons loading hatch
4. Forward escape hatch
5. Sail access hatch
6. Trim tanks/ballast tank ports
7. XBT launcher
8. Seawater coolant flow hatch? in a SSN that is.
9. Inlet for the seawater to freshwater conversion tanks
10. Aft escape hatch
11. Countermeasure launcher
12 Main drive shaft
13. Maybe a waste disposal hatch? To dump sewage?

Anything I'm missing?

EDIT: Stuff I forgot.

14. Sail penetrating mast like the scope, exhaust, snorkle, hole, etc.
15. Auxillary seawater intake
16. Hydraulics for control surfacts (I didn't realize these were originating inside the pressure hull.
17. Other stuff that I don't even know what they do. :doh:

[TLAM Strike]

The masts and Scope.

[Deathblow]

Oh yeah!! Forgot about those.

Except for the new VA with non-penetrating mast :|\ :)

edited list.

[Bill Nichols]

The masts and Scope.

Not all masts penetrate the pressure hull.

Trash Disposal Unit (TDU).

Seawater cooling for the Emergency Diesel.

Don't forget the diesel exhaust and main air induction (i.e., snorkel).

[Bubblehead Nuke]

Lets see.. on a 688 flight II

Forward:
Torpedo tubes (X4)
Torpedo ejection pump door (x2, one for each bank)
Weapon Shipping hatch
Periscopes (x2)
Bridge Access Hatch
Various VLS hydraulic lines
Sanitation overboard fittings (x2 - one above and one below the waterline)
Floating wire antenna
Forward Escape trunk
Snorkel induction Mast (doubles as ventilation shaft)
Diesel Exhaust
Diesel seawater inlet and outlet
Hydrogen overboard dump
Trash Disposal Unit
3" countermeasure tubes (x2)

Aft:
Steam Generator Blowdown (x2)
Main Seawater Inlet (x2) & Outlet(x2)
Aux seawater inlet and outlet
PCST overboard
Stern planes & rudder hydraulic ram
Shaft
After escape trunk

[Bill Nichols]

Lets see.. on a 688 flight II

Forward:
Torpedo tubes (X4)
Torpedo ejection pump door (x2, one for each bank)
Weapon Shipping hatch
Periscopes (x2)
Bridge Access Hatch
Various VLS hydraulic lines
Sanitation overboard fittings (x2 - one above and one below the waterline)
Floating wire antenna
Forward Escape trunk
Snorkel induction Mast (doubles as ventilation shaft)
Diesel Exhaust
Diesel seawater inlet and outlet
Hydrogen overboard dump
Trash Disposal Unit
3" countermeasure tubes (x2)

Aft:
Steam Generator Blowdown (x2)
Main Seawater Inlet (x2) & Outlet(x2)
Aux seawater inlet and outlet
PCST overboard
Stern planes & rudder hydraulic ram
Shaft
After escape trunk


What he said! :yep:

[Henson]

Lets not forget depth sensors.

The answer to your question is more than you could possibly expect.

All hatches and trunks, hull & backup valve sets, weapon/CM tubes and associated equalizing valves, etc.

Why do you want to know? Is there a project you're working on or are you just interested?

[TLAM Strike]

The masts and Scope.

Not all masts penetrate the pressure hull.That’s why I left it ambiguous. ;) :lol:

At least the cables from each mast penetrate the pressure hull. :D

[Kapitan]

Dont forget the russian version of a quick shower !

[Deathblow]

Lets see.. on a 688 flight II

Forward:
Torpedo tubes (X4)
Torpedo ejection pump door (x2, one for each bank)
Weapon Shipping hatch
Periscopes (x2)
Bridge Access Hatch
Various VLS hydraulic lines
Sanitation overboard fittings (x2 - one above and one below the waterline)
Floating wire antenna
Forward Escape trunk
Snorkel induction Mast (doubles as ventilation shaft)
Diesel Exhaust
Diesel seawater inlet and outlet
Hydrogen overboard dump
Trash Disposal Unit
3" countermeasure tubes (x2)

Aft:
Steam Generator Blowdown (x2)
Main Seawater Inlet (x2) & Outlet(x2)
Aux seawater inlet and outlet
PCST overboard
Stern planes & rudder hydraulic ram
Shaft
After escape trunk

Hey I did pretty good for a civilian. :cool:

*Making some edits*

btw what's the "Steam Generator Blowdown" and the PCST overboard? Oh and a "Hydrogen overboard dump"? Sounds like something outta StarTrek.

[TLAM Strike]

btw what's the "Steam Generator Blowdown" and the PCST overboard? Oh and a "Hydrogen overboard dump"? Sounds like something outta StarTrek.If it was from Star Trek it would be a Deuterium overboard dump. ;) The SGB I think ventilates the turbines and stuff, but I could be wrong.

[TopTorp '92]

I will be surprised if anyone can list all the penetrations. There are over 10,000 valves on a 688. Most submarine qualified persons will know those valves that are central to good damage control and they will know the valves central to their normal duties.

Excellent comments from Bill and Bubblehead Nuke above.

Vertical Launch System (VLS) on those 688s that have them:
*There is a pressure & vent control system that penetrates the hull. Major system components are inside the people tank. The system uses 700lbs air.

*In addtion to the torpedo tubes and other components mentioned by Bubblehead Nuke (a former shipmate of mine) the torpedo system uses equalization valves that must penetrate the hull. (Don't forget that the torpedo ejection system uses 2000 lb air.)

Other ship systems using valves that penetrate the hull:
*The sanitary system can either blow or pump to sea through PL-49 (I think I have the correct valve number.)
*The trim system has a blow and flood system to hover. I only used it for training and I used the flood part of the system for a couple of emergency deep executions. There are 4 Aux tanks on a 688. The blow & flood system uses Aux 1 & 2. The remaining portions of the trim system are excluded because they are not normally pressurized to sea. 700lb air is used to pressurize the tank and blow water to sea.
*The trim & drain systems each have hull valves in order to pump to sea. So, that is an additional two valves. I suppose that back-up valves should count as well. Make that an additional 4 valves. If I recall correctly, the flood & blow system anly ties a portion of the trim system. So, it is possible to uses Aux 1 & 2 for flood and blow operations while using the trim pump to pump water from tank to tank or from tank to sea. The reason I bring this up is because during a flooding casualty or any other casualty requiring rapid dewatering of the ship, the trim system can be used to generate some extra buoyancy. Also, the drain system can be cross-connected to dewater trim tanks and vice-versa.
*Emergency Main Ballast Tank Blow System (EMBT.) This system has hull valves actuated from the BCP. The back-up hull valves are always open. The hull valves are normally shut.
*The ship's whistle uses 150lb air in order to function. These hull & back-up valves are manually operated.
*Ship depth guages use hull & back-up valves actuated from the crews mess. 2 valves: hull & back-up.
*The hydraulics for the ships anchor penetrates the hull.

Do mechanical system penetrations count? There are too many for me to remember.
*MBT vent valve linkages penetrate the hull. These valves are hydraulically operated but the hydraulics remain inboard. However, the linkages penetrate the hull. There is also an indicator for each valve: open or shut.
*Mechanical indicators for a variety of hull penetrations themselves penetrate the hull.
*The TDU ball valve has a mechanical indicator.
*Torpedo muzzle doors each have a mechanical indicator.
*Torpedo ejection pump doors have mechanical indicators.
*The torpedo system has an equalization valve. However, I have no recollection whether it had a mechanical indicator.
*Rudder & stern planes use mechanical linkages for normal operations that penetrate the hull. I have since forgotten whether the bow planes or fair water planes use emergency back-up systems that rely on any form of a mechanical linkage back up. But if they do, then these linkages also penetrate the hull.
*Don't forget each 3'' launcher muzzle door has mechanical indicators.
*Many more . . .

Top Torp

[Deathblow]

Nice that's some good info. Not a description that going to be found in any library book. Thanks. No wonder the the max depth of a sub is so much shallower than the actual projected steel strength, with all those valves the probability of failure is compounded more and more.

[Bubblehead Nuke]

I will be surprised if anyone can list all the penetrations. There are over 10,000 valves on a 688. Most submarine qualified persons will know those valves that are central to good damage control and they will know the valves central to their normal duties.

And just were are most of them?? Yep, aft

Excellent comments from Bill and Bubblehead Nuke above.

Why thank you.

Bubblehead Nuke (a former shipmate of mine)

shhhhh.. thats a secret! Oh well, cats out of the bag now :)

the torpedo system uses equalization valves that must penetrate the hull. (Don't forget that the torpedo ejection system uses 2000 lb air.)

The equalization system, if I remember correctly, was so that you could open the outer doors after flooding the tube. It was only exposed to sea pressure when the ejection pump door was open. There was not a seperate isolation for it.

As for the 2000# air used. Oh yeah, how could ANYONE forget venting the ram inboard after shooting a weapon. A 688 shooting a torp makes a VERY distictive noise transient as you pointed out to me YEARS ago.

*The trim system has a blow and flood system to hover. I only used it for training and I used the flood part of the system for a couple of emergency deep executions. There are 4 Aux tanks on a 688. The blow & flood system uses Aux 1 & 2. The remaining portions of the trim system are excluded because they are not normally pressurized to sea. 700lb air is used to pressurize the tank and blow water to sea.

Crud, I can't BELIEVE I forgot that one.

Add Trim and drain system to the list. One fore and one aft. Additionally to using this system to move ballast around a boat, you could open interior hull suctions and use the system to move water out of the largest tank on the boat, the ones that hold the people!

Also, I do not think our boat HAD a hover system on it. I know that the later 688i's had them because it is used to pop thru the ice.

So, that is an additional two valves. I suppose that back-up valves should count as well.

This is a VERY good point for you non-quals out there. EVERY hull penetration greater than 1" (I think that was the smallest pipe size) has a primary and then a secondary isolation valve.

*Emergency Main Ballast Tank Blow System (EMBT.) This system has hull valves actuated from the BCP. The back-up hull valves are always open. The hull valves are normally shut.

I think I need to requal!

*The ship's whistle uses 150lb air in order to function. These hull & back-up valves are manually operated.

Ok, that is an EASY one to forget.

*Ship depth guages use hull & back-up valves actuated from the crews mess. 2 valves: hull & back-up.
*The hydraulics for the ships anchor penetrates the hull.

Do mechanical system penetrations count? There are too many for me to remember.
*MBT vent valve linkages penetrate the hull. These valves are hydraulically operated but the hydraulics remain inboard. However, the linkages penetrate the hull. There is also an indicator for each valve: open or shut.
*Mechanical indicators for a variety of hull penetrations themselves penetrate the hull.
*The TDU ball valve has a mechanical indicator.
*Torpedo muzzle doors each have a mechanical indicator.
*Torpedo ejection pump doors have mechanical indicators.
*The torpedo system has an equalization valve. However, I have no recollection whether it had a mechanical indicator.
*Rudder & stern planes use mechanical linkages for normal operations that penetrate the hull. I have since forgotten whether the bow planes or fair water planes use emergency back-up systems that rely on any form of a mechanical linkage back up. But if they do, then these linkages also penetrate the hull.
*Don't forget each 3'' launcher muzzle door has mechanical indicators.
*Many more . . .

Top Torp

Ok, the mechanical indicators were easy. They were switches at each end of the bellcrank that operated the valve in question. In the even of electrical failure you can LOOK at the things and see what position they were in, they were not physally ON the valves themselves but on the hydraulic operators. It was presumed that the operating lever would not break. There was not an actually electrical penetration involved.

On the stern planes and the rudder, there are graduated scales that can tell you current rudder/plane position in the hydraulic ram. I don't know HOW many times during a JAM DIVE drill I had to take manual control of the stern planes and return them to neutral. I DO know I could take manual control without looking at the book, in about 15 seconds. It was 4 valves if I remember correcly. Climbing up to the things at a 30 degree down angle.. now that took a bit longer.

[Bubblehead Nuke]

Nice that's some good info. Not a description that going to be found in any library book. Thanks. No wonder the the max depth of a sub is so much shallower than the actual projected steel strength, with all those valves the probability of failure is compounded more and more.

Each system exposed to seapressure is designed to handle it. It is not so much a lack of strength but how fast things can south when things go wrong.

You should see the flood trainer we go in. It starts out small, then they kill propulsion on you. As the ship gets deeper the leak rate increases and you sink faster building seapressure FASTER. Thus MORE water comes in. It does not take to long before the instructor says 'BANG' on the intercom.

[Bubblehead Nuke]

btw what's the "Steam Generator Blowdown" and the PCST overboard? Oh and a "Hydrogen overboard dump"? Sounds like something outta StarTrek.

Steam generator blowdown and PCST are nuc things. TMI for the most part.

Hydrogren overboard dump. Okay, we make our own oxygen underway. You do that by splitting Hydrogen and Oxygen (aka. h20, also known as water, something you have LOTS of access to). When you do that, you let the oxygen inboard and you have to do SOMETHING with all that hydrogen. You let it go right over the side (so to speak).

Gotta beathe, gotta eat, and you gotta poop. Sleep is optional.

[Deathblow]

Sweet five ex-nukes on the forums. Bill, Bubblehead, Henson, and TopTorp, and SubSailor.... hm... who else am I forgetting. Nice know that some opinions are based on RL experience and not internet browsing like my own :lol: :-? :oops: :(...

...though I have read a book or two... http://www.subsim.com/phpBB/viewtopic.php?t=51686

[TLAM Strike]

...who else am I forgetting.

Sonar732 ;)

[sonar732]

Good times, good times...here is the damage control trainer.

https://www.npdc.navy.mil/slc/nss/dct041901.htm

The fire trainer...

https://www.npdc.navy.mil/slc/nss/fft051501.htm

and escape trainer...

https://www.npdc.navy.mil/slc/nss/etf041901.htm

:rock:

Thanks for the heads up TLAM!

By the way, an Ohio class boat has 3 escape trunks...would you count 24 missile tubes?

[SeaQueen]

I like the touch screens in the Virginia class trainer.

[SeaQueen]

Not all masts penetrate the pressure hull.


Wouldn't there still have to be cables connecting non-penetrating masts to whatever gizmo inside the hull that's associated with it?

[TopTorp '92]

Excellent comments from Bill and Bubblehead Nuke above.
Why thank you.
quite welcome :lol:
The equalization system, if I remember correctly, was so that you could open the outer doors after flooding the tube. It was only exposed to sea pressure when the ejection pump door was open. There was not a seperate isolation for it.
As for the 2000# air used. Oh yeah, how could ANYONE forget venting the ram inboard after shooting a weapon. A 688 shooting a torp makes a VERY distictive noise transient as you pointed out to me YEARS ago.
There are tactical issues associated with the torpedo tube selection. You always shoot the target using an opposite tube. Starbard tubes are used to shoot portside targets; likewise, port tubes are used to shoot starbard targets. Studies have shown that the target is likely to fail detecting the transient associated with a tube fired on the opposite side of the ship. This has everything to do with the fact that the ships aspect exposes the operating noises for that aspect. The transient reduction alone will spell the difference between a target that alerts early and one that fails to alert at all.
*Emergency Main Ballast Tank Blow System (EMBT.) This system has hull valves actuated from the BCP. The back-up hull valves are always open. The hull valves are normally shut.

I think I need to requal!
get hot! :know:
*The ship's whistle uses 150lb air in order to function. These hull & back-up valves are manually operated.
Ok, that is an EASY one to forget.
. . . only because it was forward of the watertight door :yep:

[TopTorp '92]

Not all masts penetrate the pressure hull.


Wouldn't there still have to be cables connecting non-penetrating masts to whatever gizmo inside the hull that's associated with it?

In a word: yes. Electrical fittings are so numerous they are not worth mentioning. There is a separate hydraulic system associated with sail components. Hydraulic system components are located inboard (AMR) while the hydraulic lines are fitted to the hull.

[Henson]

Not all masts penetrate the pressure hull.


Wouldn't there still have to be cables connecting non-penetrating masts to whatever gizmo inside the hull that's associated with it?

In a word: yes. Electrical fittings are so numerous they are not worth mentioning. There is a separate hydraulic system associated with sail components. Hydraulic system components are located inboard (AMR) while the hydraulic lines are fitted to the hull.

EHP's (Electrical Hull Penetrations)

They are NUMEROUS, especially when talking about boats with external tubes (VLS, or flight II 688's)

Working on those can be interesting. Nothing like sitting in a ballast tank and looking through the pressure hull into the people-tank while one is being repaired. We really trust those welders, don't we?