USS Connecticut collision

Subs colliding with the sea floor, i.e. submerged groundings, take place during training and the structural damages are easy to verify. Subs colliding at the surface of the sea with other ships, i.e. not being submerged also takes place. The structural damages of the sub are at the top of the sub. I fear USS Connecticut collided with a steel trawler that is now at the bottom of the sea.

You could make a fortune with that imagination of yours if you did something constructive with it, like writing fiction. Oh, wait….

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I thought you asserted that a US sub “launched a boulder” into the Costa Concordia. Oh. I forgot. that was a pint and a nip ago. Haven’t you got any new material?

It isn’t a grand scheme. Its just mother nature and cavalier seamanship (reinforced by ego and militaristic madness) Maybe pingpong balls and magnets are the cause. Do tell.

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No problem, the navy has a lot of experience using FoC heavy lift ships to haul their broken ships around.

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You mean like in this case?:

COSCO has a few HLV that could do the job on short notice:

Actually the US Navy got a few HLV themselves:

They only need to remove that extra deck they put on them:

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You make the point. You have not been there to make intuitive sense. Further they are not going to tell you what the boat was doing (actual speed, bubble, roll, stations, etc.) when it hit. AND they are not as roomy as the movies or “a week on the USS Never Sail” show.

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OldNuke, in your opinion, could a collision with a 40ft container cause injuries to the crew on watch ?

More to the point, what might be the impact (pun intended) of hitting a 76 ton object at whatever speed the boat was making at the time?

Does a 40ft container have neutral buoyancy at 76 tons ?

I have no idea.

It depends on the nature of the contents and the amount of air trapped inside. From Cargo-Partner newsletter:

Most containers sink quite rapidly to the ocean floor once they hit the water. But depending on their contents, they may stay afloat for days or even weeks before sliding beneath the surface. This process can take even longer for refrigerated containers on account of their buoyant insulation. For example, one container that washed into the Atlantic off the coast of France rode the waves for eleven months before finally being deposited on the southern coast of Great Britain.

Bouyancy has nothing to do with impact. The mass of the water filled container has everything to do with it.

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The neutral buoyancy of a watertight 40ft container is around its weight of 76 tons.

An empty 40ft container weighs 8,000 lbs.

The mass of a water filled 40 footer is 76 tons. A submarine colliding with the container will experience the same impact as a wheeled vehicle running into a 76 ton object at the same speed.

so its needs 8000lbs of positive bouyancy and rest can be water?
3000kg = 3 cubic metres of air?

To float at the water’s surface or just below it needs only enough bouyancy not to sink, a few pounds will do nicely in calm water.

76 tons is the mass of the water an “empty” 40 footer can hold. Its actual mass depends on what is in the container and the weight of the container structure itself. If it’s filled with ping pong balls it will float with some degree of freeboard, if it’s filled with anvils it will sink, worst case for vessels running at or just below the surface a neutral or slightly bouyant box might be at, above, or just below the surface.

Bouyancy only determines where it is relative to the sea surface, mass determines how much damage it might do when hit by a vessel.

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yes I was pointing out only 3cubic to float it and rest can be water so 60ish tonnes of water plus the 3 tonne of corten steel

I’m no expert on submarine stability, but I have researched them for the last couple of years. And what has struck me is how difficult it is for submerged objects to achieve neutral buoyancy and maintain it. A lot of engineering goes into designing subs to do it. The early subs were always pogoing up and down at depth because the slightest force in either direction knocked them out of equilibrium, and that was with active engineering control.

A submerged container achieving neutral buoyancy–just floating at a given depth–seems to me unlikely. To strike one at depth while it is sinking is just as much or more statistically improbable, because sinking is a transitory state. Doesn’t mean it couldn’t happen of course.

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And all but impossible.

Military subs maintain depth by “flying”, dynamic depth control by motion and bow and stern planes. When I was driving deep diving manned submersibles (Pisces, Aquarius) we could achieve very close to neutral but for all practical purposes relied on thrusters to maintain depth. We could “park” on a thermocline in midwater because we were capable of trimming very small amounts of ballast water.

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