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Old 01-10-2008, 16:47   #121
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Why? With all that metal in the water providing a good path for the lightning surely you would make a better target?

Dave
You followed the link?

Metal in water = path for lightening (which doesn't include me)
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Old 01-10-2008, 17:17   #122
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Lotta neat sounding science (not) in that ad.

Thanks.
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Old 01-10-2008, 17:27   #123
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Lotta neat sounding science (not) in that ad.

Thanks.
I know. Pretty weak, but we're having fun here, right?

Actually, I couldn't find the site I was looking for. It lists the comparitive dangers of monos and cats in fresh and salt water (conduction greater in salt). The list from safest to most dangerous goes...
1/ mono in salt
2/ cat in salt
3/ mono in fresh
4/ cat in fresh

Lots of cool science there but I'm too lazy. I'm certain someone here has seen it.
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Old 01-10-2008, 17:34   #124
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I know. Pretty weak, but we're having fun here, right?


.
OOPS......I forgot.
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Old 01-10-2008, 17:56   #125
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139 - Everyone knows cats are afraid of water

140 - 3 AM - Full Keel, 5 kts, 30,0000lbs / No keels, 7kts, 16,000 lbs - What would you rather hit a container with?
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Old 01-10-2008, 18:04   #126
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Biggest Rubicks Cube I ever saw...
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Old 01-10-2008, 18:25   #127
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140 - 3 AM - Full Keel, 5 kts, 30,0000lbs / No keels, 7kts, 16,000 lbs - What would you rather hit a container with?
Actually (and it pains me to do this), if you use the old f=ma you'll see that the mono will hit with a force 1.339 times that of the cat. If the cat hits bow-on, double that number to 2.678 because the force will be spread over the two bows. Since the extra weight of the mono is in the keel, the keel will tend to keep moving while the rest of the boat stops which will result in, at best, a squished bow, and at worst, a detached keel with the oh soo exciting immediate sinking. The cat, due to its lighter weight and dispersed impact might be expected to, more or less, bounce off (I know, a severe understatement). I'm no physics prof. but I'll have to give that one to the cat. (Yes, it's killing me)
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Old 01-10-2008, 18:43   #128
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Actually (and it pains me to do this), if you use the old f=ma you'll see that the mono will hit with a force 1.339 times that of the cat. If the cat hits bow-on, double that number to 2.678 because the force will be spread over the two bows. Since the extra weight of the mono is in the keel, the keel will tend to keep moving while the rest of the boat stops which will result in, at best, a squished bow, and at worst, a detached keel with the oh soo exciting immediate sinking. The cat, due to its lighter weight and dispersed impact might be expected to, more or less, bounce off (I know, a severe understatement). I'm no physics prof. but I'll have to give that one to the cat. (Yes, it's killing me)
Interesting reply f=ma, I agree...

What happens next can be debated. he "extra" weight of a mono is in the keel "and" the "single" hull.

The "lighter" weight of the cat is in two hulls and a bridge deck. The only way this is possible, conjencture and not picking a fight mode, is if the average hull thickness is less.

Bowsprits, anchor rollers, yada, yada. I'll vote for the "average" full keel, heavyweight.

Also - There are 360 degrees in a circle. There is only one number on that circle that result in both bows hitting the container simultaneously. OK I'll give you 10 degrees - let's call it chances are 35:1 - Isn't that about the same odds as a roulette wheel -

Also, thinking out loud mode. If the cat hits "angle off" with the starboard hull, would the forces turn the cat into the container?

An off angle hit on a mono is likely a deflection.

There are also the considerations of the container. Rather than blather on consider the SUV vs the Yugo. SUV has crap loads more m*a but that's the vehicle I'd be in.
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Old 01-10-2008, 18:56   #129
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Ex-Calf, I agree. It's mostly academic. The admiral drives a sedan while I drive an SUV. We're both paste if we get t-boned by a transport. It'd surely suck to hit a container ship regardless of conveyance.

Let's just agree that monos rule.
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Old 01-10-2008, 18:58   #130
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Sorry, that's Ex-Calif. No cow jokes intended.
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Old 01-10-2008, 19:17   #131
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So, does a cat flying a hull, or a tri flying 2 hulls count as a mono?
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Old 01-10-2008, 19:24   #132
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So, does a cat flying a hull, or a tri flying 2 hulls count as a mono?
Only in that they're finally actually sailing.
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Old 01-10-2008, 20:21   #133
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You followed the link?

Metal in water = path for lightening (which doesn't include me)
Yep, followed the link, I was always under the impression that lightning takes the easiest path.

So that would mean its attracted to the one with big lumps of metal in the water wouldnt it?

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Old 01-10-2008, 20:45   #134
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Interesting reply f=ma, I agree...


The "lighter" weight of the cat is in two hulls and a bridge deck. The only way this is possible, conjencture and not picking a fight mode, is if the average hull thickness is less.
Well, another way it would be possible is if a large proportion (ie. half) of the boat's weight wasn't lead.

A cat I know ran into what they think was a semi-submerged container. It was something heavy with a sharp corner anyway. The boat mostly rode up over it, but there was a small hole made in the bow, where the airtight bouyancy chamber is. It didn't affect the boat at all, on that trip.

When they were back in a marina, he moved all the stuff out of the stern locker on the opposite hull, plugged the drain and filled it with water. (A couple of tonnes) The damaged bow lifted clear of the water, he drilled a couple of holes and used compressed air to dry out the bouyancy chamber, and then repaired the damage and the holes he had drilled (which were actually bigger than the damage)

Overall I'd say hitting a container didn't turn out to be much of a drama for them.

Back on topic:

141: You don't miss any scenery - even when you've been off watch and asleep for 4 hours, the scenery is just the same when you come back on deck.
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Old 01-10-2008, 21:01   #135
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Dave,

I used to use your "bounce off" logic on my Dad, when I tried to convince him a VW Bug was safe. Now, seriously, how does that logic look?? BTW, I bought a 7 year old Mercedes after he helped me re-visit my high school physics!
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