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Old 08-09-2010, 02:16   #16
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Originally Posted by mintyspilot View Post
OK - here's a thought. A big wave hitting a big ship is a bit like the old conundrum of the irresistible force meeting the immovable object. A big ships' inertia stops it moving with the wave and this translates the wave force into tipping the ship.

Would you actually be better off in a small boat (assuming it is properly watertight). At least a yacht with its smaller inertia would be able to ride up and down the wave more than a cruise liner.

I'm not saying you won't spill your coffee in a yacht.....
A friend of mine, a retired Pilot, swears by this. He would prefer being in the bunk of his 28-footer, well battened down, than banging into the waves (hurricane off Hawaii)on the bridge of a big tanker...

gives me som level of comfort, keep wondering what it would be like, but not quite wanting to 'try it at home'.
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Old 08-09-2010, 02:36   #17
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In my former life, I was on an USN aircraft carrier off Puerto Rico for two days in an unforecast 50-55 knot blow, we suffered lots of damage, but mostly the aircraft stayed tie down albeit broken tie down chains were plentiful. One death when a hanger bay door came loose! I have also been in 45 knots, two day storm off New Caledonia on my current boat, a 12 meter sloop. I must say I was much more comfortable being heaved to on the smaller boat, not nearly so much bashing or rolling!
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Old 08-09-2010, 06:45   #18
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Would you actually be better off in a small boat
The force of gravity is constant for all things. The force of a wave is equal on both the ships because the mass of the water is almost infinite compared to either vessel. The velocity you reach flying into the immovable object is measured as 1/2 * Acceleration * Time squared.

Basically the longer you are in a free fall, the faster you smack into an immovable object. Jumping off a high building vs. falling down the companionway. Same gravity acceleration but longer time yields faster terminal velocity.

In one case where your ship falls off a wave, you hit bottom it really won't matter if you are secured. The sudden deceleration can cause bodily internal organs to have a different velocity inside you when your body stops. Being secured has limits probably equal in both boats.

When the boat pitches you travel faster than the boat if not secured and smack into something sooner on the small boat than across the large open saloon on a big ship. It's the relative velocity difference between the boat and your body that gives the little boat the advantage but only for that situation.

It's the relative difference in velocity that kills you in a plane crash unless parts of the plane break off and have a relative difference in velocity. Thus being struck by a slow moving fork lift has serious effects but a grapefruit just hurts when you are stationary.

Being strapped in saves you a lot of potential trouble but it is only effective if everything else is strapped down too.
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Old 08-09-2010, 07:54   #19
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Another issue is that a ship doesn't stop all at once, causing twisting and flexing along it's length. Doing that in really big seas soon exceeds it's design limits...
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Old 08-09-2010, 08:31   #20
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Well, of course there are various propagators of the "cork" theory of smaller boats including examples of steel hulls on tankers caving in resisting to the waves. However, you also should consider rolling issues which I think might be an offset - a breaking wave 50-60% of LOA taking you 360 might have issues on it's own.

I had idiotic fantasies of taking an old ship life boat and sticking a telescopic mast on it, or maybe one of those english power lifeboats that can do 360's all day long in the surf.
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Old 08-09-2010, 08:41   #21
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Quote:
Originally Posted by SaltyMonkey View Post
Well, of course there are various propagators of the "cork" theory of smaller boats including examples of steel hulls on tankers caving in resisting to the waves. However, you also should consider rolling issues which I think might be an offset - a breaking wave 50-60% of LOA taking you 360 might have issues on it's own.

I had idiotic fantasies of taking an old ship life boat and sticking a telescopic mast on it, or maybe one of those english power lifeboats that can do 360's all day long in the surf.

Why not? question being how long YOU can take 360's in the surf?

doesn't seem like an interesting pastime, but lifeboat-shaped boats has a LOT speaking for them IMHO.
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Old 08-09-2010, 10:41   #22
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Would you actually be better off in a small boat (assuming it is properly watertight). At least a yacht with its smaller inertia would be able to ride up and down the wave more than a cruise liner.

..
Tell that to George Clooney in The Perfect Storm.
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Old 08-09-2010, 12:06   #23
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Tell that to George Clooney in The Perfect Storm.
Of course, in the Satori incident, the crew abandoned the boat on the order of the USCG during the perfect storm that the Andrea Gail foundered in and the boat was just fine and was found a few days later...

Westsail 32 - Wikipedia, the free encyclopedia
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Old 08-09-2010, 13:08   #24
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That must have been a BIG Bayliner wake...
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