I made an account just to ask this question. It’s been bugging me that much.
Is there a term for when a boat is sinking and it releases a last breath? All the air is trapped in the bow and its like a sudden decompression. I have asked everyone I know and have come up short. Please help!!!
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Colibri
General Questions Moderator
Well are you talking about a BOAT or a boat? 
A BOAT being a 1000+ foot on the Great lakes or are you referring to a 16 Ft. runabout on the lake?
A pleasure craft will have floatation and will stay at the surface for the most part, but I am envisioning the sinking of the Titanic in your question.
Air stays trapped in a boat only as long as the boat stays air tight in places. The bow is generally a strong part of the structure and you don’t put doors or portholes there, so you can see why it might often stay air tight. If enough air is trapped there, the buoyancy could prevent the rest of the ship from sinking. In that case, nothing sinks until the air in the bow finally escapes.
But I’m not sure that the phenomenon you’re describing is a universal method of boat-sinking - there are lots of ways to sink. I’d be tempted to blame Hollywood on this one, since it gives you a nice dramatic ending.
I assume you mean when it’s nearly completely below the water, the sound of any trapped air finally escaping and making a, well, rushing air sound (like a hole in a balloon)? As far as I know there’ no olde timey seadog word for that.
I recently read that there was still a lot of air trapped in the stern section of the Titanic when it sank, and supposedly when it got a couple hundred feet down there was an implosion that was heard on the surface. Is that correct? That would seem to be a pretty dramatic example of the kind of thing the OP is talking about.
I would wager that what you’re mostly used to seeing is when (in the making of a TV show or movie) the special effects guy hits the release switch and a valve opens to let the last of the air out so the boat sinks on cue. Unless you’ve been in a situation to see lots of boats sink for real, which would be an interesting story.
TV, movies and cartoonists also use this imagery for a drowning person as well. It’s a nifty metaphorical exclaimation point for a person’s or ship’s confirmed demise.
Just to confirm, OP is asking about, say, a death- glorious ship, with its three unsurrendered spires; uncracked keel; and only god-bullied hull; firm deck, and haughty helm, and pole-pointed prow.
Specifically he asks, Must it then perish?
And in what manner? OP has in mind, I believe something like this:
Small fowls flew screaming over the yet yawning gulf; a sullen white surf beat against its steep sides; then all collapsed, and the great shroud of the sea rolled on as it rolled five thousand years ago.
I’m just trying to clarify matters. I don’t know a word for the sound it makes. Narrating such an event as I create it in my bathtub, I would say “gurgle, gurgle.”
I’m picturing and hearing the effect you get from a water cooler.
Well, I was just giving an excerpt.
A usual bathing experience would include thunderous claps on the water, accompanied by a combination of “heeelllp were sinking”, “blast ye, the lifeboats!”, “women children and duckies first!”, “the loofah, the loofah, what about the loofah!”, “shpshsh, shpshsh”, “Oh the humanity”, loudly bellowed snippets of Nearer My God to Thee, and cries of “we’re going down!” and “is there nobody to come to our aid?” to my unheeding and unabashedly uncaring wife trying to read in the bedroom.
Let’s make some up!
**Burping Neptune.
**Titanic fart.
The term I have heard used to describe what the OP is asking is “death throes”. As in the “death throes of a sinking ship”.
You could read this chapter: Shackleton’s South Chapter 4. Lots of descriptions of the sound of a sinking ship. Of course this one was crushed by ice over a period of weeks, but there is in the book a description of its final demise.
I believe in the Navy, officers refer to it as “noise”.
Enlistred personnel call it “fuckin’ noise”. (The adjective --or adverb-- applied to everything wehen you’ve been out tos sea for a while.)
Regarding a drowning person, this actually (usually) does happen: when the instinct to breathe caused by the buildup of CO2 exceeds the instinct not to inhale underwater, we expel our last breath and suck in the water. After this point is when the “nice” part of drowning begins: we no longer feel the urgent need to breathe, and can “enjoy” observing our faculties shutting down as our brains are deprived of oxygen.
Some people have stronger instincts not to breathe underwater and never reach this point, even when unconscious. These people are much more likely to survive if rescued.
But I’m sure you’re right that the reason they do it in the movies has nothing to do with reality.
I’ve observed a couple of ships deliberately scuttled, to become artificial reefs. Depending upon the rate at which they are going down, and the number and size of holes through which trapped (and thus compressed) air can escape, there may be some moments when significant amounts of air emerge from a submerged hole or holes, pushing water upward and causing something like a geyser at the surface. These can occur throughout the process, not just at the very end.
I think that the formal, professional word of art for this is “sinking”. 
At least that’s all I’ve ever heard it called.
There seems to be a persistent belief that a sinking ship will somehow drag down lifeboats (nearby) with it. In the movie “Titanic”, a seaman commanding a lifeboat tells the people to row away from the ship, because he fears that the lifeboat will be pulled down.
Is this true? Are seamen told to move away from a sinking ship?
It is true that they’re told to move away from a sinking ship. (I don’t know if it’s still true, but it was certainly the conventional wisdom at points in history.)
Whether the being sucked down part is true… that’s a little questionable. There’s certainly a chance of being caught in the rigging and dragged down, so that’s one real risk that would look similar to being sucked down even though it’s a different event. There is evidence that bubbles in water reduce buoyancy, so enough bubbles would make you sink… but I doubt that most sinking ships produce enough bubbles to have a significant effect.
In the US Marine water safety manual I saw from a cite in GQ (actually my own cite, come to think of it :)), you are advised to get as far away as possible to avoid burning fuel, or noxious chemicals of any kind.