View Full Version : Question for any submariner on the board.

eastern wiseguy
28th May 2014, 22:09
I spent part of today looking around the USS TORSK in Baltimore. One of the instruments which stood out was an altimeter. It didn't have a means of setting a pressure on a subscale .

Can anyone tell me its purpose? Nephew asked ......and I had no idea.

On a totally unrelated note . Kudos to ANYONE brave enough to have served on board a submarine. I felt claustrophobic just moving through it let alone fight on one.

28th May 2014, 22:14
measuring air pressure when the diesels are running (http://www.submarinehunter.com/tag/altimeter-on-submarine/)

28th May 2014, 22:41
How do submariners control the pressure inside the hull when the sub dives to very deep depths?

I assumed that the altimeter would indicate theoretical depth, but an aircraft altimeter is open to the atmosphere and registers outside pressure, whereas it seems that the submarine altimeter measures internal pressure (or is that too simple?).

Does the internal pressure work like an aircraft - but in reverse?
Equalising the internal pressure with the external (water) pressure would cause the occupants to experience the bends, Shirley?

28th May 2014, 23:20
Imagine all hatches closed and diesels running, air being sucked into the diesel

tony draper
29th May 2014, 09:09
I think subs operate with a internal environment of one atmosphere,its the pressure hull that resists them being squished.

29th May 2014, 12:37
....having spent some time in a French navy Daphne class..

When the sub is snorting ALONG the swells, sometimes the air intake valve in the mast is "buried for a fair length of time". The diesels will continue to run on the air in the hull thereby reducing the pressure in that space, and in the process giving ones eardrums a fair exercising. However when the pressure drops by 200mb (old money) the engines will shut down. That equates roughly to about 6000feet altitude.

However (again) when the intake mast emerges into clear air again the pressure in the hull drops to sea level in a millisec. Lots of nose pinching and swallowing going on. Then it gets covered again and the pressure begins drop again.........

When the subs track takes it ACROSS the swells the intervals are much shorter and the pressure changes much more rapid.

It renders life bloody uncomfortable and sleep well nigh impossible

Tell the younguns nowadays and they wunt believe you.

The Ancient Mariner

tony draper
29th May 2014, 12:43
Yer and the Subs all have inside toilets these day as well.:)

29th May 2014, 12:49
I think subs operate with a internal environment of one atmosphere
How is this pressure (and atmosphere) maintained when the sub is submerged - and where does the air come from?
A sealed capsule would suffer from oxygen depletion due to the crew breathing (and, possibly, an increase in water vapour?).

tony draper
29th May 2014, 12:55
They probably have carbon dioxide scrubbers,like the astronauts had in their wee spacehips.
Only ever aboard one submarine and I was only ten at the time so the above is a guess.
Those Nuke Missile boats stay submerged for three months at a time so they must have the means of making their own air,from what I have read it's the grub they run out of first.

Um... lifting...
29th May 2014, 14:03
Mr. D-

You have part of the equation correct. Amine scrubbers for the CO2.

The two advantages a nuclear submarine has over a wee space capsule is that it's got an essentially unlimited supply of energy and is surrounded by an unlimited supply of raw material from which to make oxygen (and hydrogen, which is pumped overboard) through electrolysis.

And so they do.

One is surprised that a man of your considerable electrickeral gifts hadn't sussed that out.

Temp & humidity are managed by more or less conventional means, balancing the chill of the oggin with the heat from the reactor to give one any temperature one might reasonably expect.

tony draper
29th May 2014, 14:11
I was thinking about them cracking water for oxygen but wondering what they did with the hydrogen,that's not summat you want floating about in the confined space of a submarine.:uhoh:
As one has oft said the place for me was on the Ogan not in the ogan.:rolleyes:

29th May 2014, 14:50
Once saw the results of sealing a 500 K.V.A. diesel - generator in a sound-proof room. It sucked the walls in when it first ran under load. The 8 inch thick walls just collapsed in a heap. Seriously impressive. :D

tony draper
29th May 2014, 14:58
It would be the pressure of the air outside yer room and the lack of it inside that squished it, Mr Crippen.:uhoh:

29th May 2014, 15:06
Presumably the exhaust was piped to outside of the room, otherwise where did the air go?

29th May 2014, 20:20
The origins of the altimeter-in-submarines is as follows.

During WW-II the British used aircraft to pour green paint over the surface of the sea where a German U-boat was believed to be. The U-boat would subsequently "up periscope" the lens of which would then be covered in green paint: not being able to see anything except a green haze the commander would order the sub up 10 metres or so. He would repeat this again but only see green paint, hence "up another 10 metres". This would be repeated until the sub was at about 1000' whereupon the British aircraft would easily shoot it down.

Observing the altitude on the altimeter would prevent this.

29th May 2014, 20:23
Tattic still used into the late 60's. Why do you think the Shacking great fukleton had 20 mil cannon in the nose?

29th May 2014, 20:49
Got me there, for a few lines, boys:D

29th May 2014, 20:57
Does anyone know something about the controls in a WW2 German U-Boot? I have a question about a certain control that I've seen in a video.

29th May 2014, 21:29
In the early 80s my boss was a lovely lady married to a senior navy guy who was in Faslane (sp), so I knew he was involved with subs in some way.

He used to call and ask for the latest City gossip and jokes and we would have a good yack. Little did I know he would be calling from under the Arctic icecap or some such. He later told me he would tell someone a joke and wait to see how long it took to get back to him. In a sub, it wasn't long!

Charming bloke. Just Goggled him and he ended up a Commodore. Must touch base with them again. :ok:

tony draper
29th May 2014, 22:00
I have a old pal who served on the Polaris boats,he said when they surfaced after a trip and cracked the hatch some of them used to vomit when they got their first wiff of fresh air, after they had been breathing canned air for three months he reckoned you have no idea how much fresh air honks until you haven't tasted it for a long time.

29th May 2014, 23:37
Hats off to all those who did submarine work.

The close quarters alone would be enough to challenge us mortals.

30th May 2014, 01:40
I rented a house in SF for quite a few years which used to belong to Charles Lockwood USN, who was in charge of the US Pacific Sub. fleet during WWII.
Our neighbour lady (old) had some of his books and gave them to me.
Derring deeds were told in them.