If a submarine suddenly ends upside down at sea, what would happen? Besides the mess, does the sub will right itself like a rubber ducky or do submariners have to maneuver the sub to a straight position? What are the dangers on the engine room on a Diesel or Nuclear sub if that were to happen?
The submarine got upside down almost instantly, I know why, but I am not telling yet, this occurs in a sci-fi tale that I am writing, and I will leave the scene without a resolution because it is not important to the plot (the baddies go to do more serious destruction elsewhere).
However, I am curious to know how a crew would react. Just assume that the hull and mariners are ok after the turn.
I would think that in order for a submarine to capsize, there would have to be a very serious (and probably unrecoverable) problem, such as extensive internal flooding; IANAEngineer, but my understanding is that the distribution of weight/ballast and empty space/flotation tanks is arranged in such a way as to keep the vessel from rolling.
All of the ballast in a submarine can be moved to trimm the boat. A situation similiar to this actually happened where a skipper ordered massive counter ballast measures to be applied to level a sinking submarine. When the skipper finally regained control of his boat, the submarine shot up from the depths of around 1100 feet or so, like a cork, breached the surface of the water, and sank to around 200 feet or so, before a more controlled ascent could be maintained.
course if you are writing a book on this you probably read about this incident already. Here is a link: http://www.lostsubs.com/SS-342.htm
Most of the stuff in subs and ships is secured so it doesn’t tumble around in rough weather. In any case modern subs have an escape trunk the crew can use to get out if the sub can’t surface.
Bouyancy for modern submarines requires that the ballast tanks be trimmed as necessary with air and the tanks have valves at the tops to keep that air in, however the bottoms of the ballast tanks are open to the sea (consider that the water which displaces that air does have to come from somewhere, ya know?)
A submarine which (for whatever bizarre reason) should happen to become fully inverted would have the air in the ballast tanks empty out almost instantly and any attempts to pump more air to replace the lost bouyancy would simply allow that additional air to escape as well. Without the support of this air the submarine would descend to the bottom (or more likely, would sink to crush depth and the hull would collapse under the intense pressure).
And before anyone comes up with any bright ideas about using the engines to bring the sub rightside up i would point out that a nuclear reactor subjected to these sort of gymnastics would have scrammed rather promptly leaving the sub powerless and sinking into the darkness (not that the sub’s control surfaces are made for the challenge of flipping a submarine back over from an inverted position anyways). Regardless, an upside down submarine is effectively a doomed one.
wolf189 (former submariner)
Even though fictional, now I feel guilty I left those background characters in that pickle! Now I feel the need to get back to them and find a way out of that scenario!
I dont know much about submarines, but I have always wondered whether one of the functions of the conning tower is to act as a boyancy tank at the top sub. A sort of inverted keel.
Perhaps someone could shed some light on this.
As a plot device, we might suppose that the submarine will roll over only when the conning tower is flodded. The submarine comes to rest on the sea bed and the crew are bright enough to realise that the conning tower must be sealed and filled with air to right the sub before they waste the precious stuf trying to blow the main ballast tanks. Just an idea.
In short, no. Most of the sail is freeflooding, in a way. As to the OP, wolf189 is quite correct, the sub would be doomed.
BF, (another former bubblehead)
I’m not sure the reactor would scram right away (I mean because of flipping over) unless you lost power to the rod control mechanisms. You would uncover the heat exchanger in the steam generators which would cause a loss of coolant so you would be toast anyway. The steam system wouldn’t contain the coolant so you’d have contamination all over the place and a reactor turning into a puddle of molten metal. Also the battery would probably not stay put so forget about that.
So even if you could right the boat propulsion and power would be gone.
Maybe the outboard would help. Do subs still have the outboard motors. My experience is over 20 years old.
If you mean the EPM (emergency propulsion motor), it runs on the battery, and only generates about 3 knots of thrust, so it couldn’t drive the boat to the surface. As noted previously, the batteries would be toast on an inversion. The diesel is also out of the picture as the snorkel mast needs to be above the surface as it is normally aspirated.
No, BF, the EPM does come off the battery but this motor poked out of the bottom of the boat a little aft of center. At least on 637 class boats.It was used for maneuvering in heavy current. It surely wouldn’t help in this case. I just wondered if they still had them.
I got my pm’s backward. On the 637 and 688 class boats the EPM was a DC motor used to turn the main shaft, and was good for only about 15 minutes on the battery. The Secondary Propulsion Motor (SPM) is deployed from center aft beneath the boat. It is hydraulically actuated to extend down and retract up into the boat. It is mainly used for low speed maneuvering, in port for example, and was only good for about 3 knots max speed.
this occurs in a sci-fi tale that I am writing, and I will leave the scene without a resolution because it is not important to the plot (the baddies go to do more serious destruction elsewhere).