On Mon, 8 Jan 2007 08:10:41 -0500, "Roger Long" wrote:

William Longyard wrote:

Geraldo Rivera said the other night that he was unable to furl his
sail(s?)

Even if he was having sail problems, this probably wasn't a wind driven
accident unless the rig had developed some fatigue weak points. Given the
extent of his preparations and expenditure, that doesn't seem likely.

A knockdown, even with too much sail, shouldn't have taken the rig out of a
boat like this; certainly not to the extent shown in the pictures. Being
rolled by large wave action with the full weight of the boat dragging the
rig, with it's enormous hydrodynamic drag, through the water is what
dismasts boats. Where inability to get the sails off factors in is their
drag making them virtually unmovable in the water. Turn the boat upside
down, bury the masts in the ground, and then expect it to withstand an
earthquake. Those are the kinds of forces we are talking about.

Boats occasionally withstand rolling without dismasting but seldom with
sails up. Minimizing drag is important if rolling is a possibility.
Something to thing about with a big sausage of rolled genoa on the headstay.

Size works both ways. The waves are relatively smaller as the boat gets
larger but, when you get into really big seas like the southern ocean, there
isn't much difference. The motion of the larger boat will be less tiring
but it takes a lot more energy to do anything on deck. When energy is
critical, managing the small boat will be much easier. When you are just
steering or hunkered down, the larger is better. If one person is pumping
by hand after flooding due to a roll or being swept, it will be a lot less
work in the small boat. Scale effects make smaller boats inherrently
stronger.

Donna isn't as crazy as it might seem to be down there in her 28 footer but
it's like climbing Mt. Everest, some are going to die. Did anyone see the
"Everest - over the limit" on Discovery Channel? Big strong guys in perfect
physical condition don't make it and old, weak, people with recent
operations do. Sailing is like that.

Speaking of being rolled:

Back when I was researching sailing vessel accidents, I read an account of a
60 foot racing sloop being delivered across the Pacific in the winter by a
professional crew. They were rolled and dismasted and limped in with a jury
rig. The timing and account of the roll didn't make any sense with the
physics until I put it into this possible scenario.

Build a tripod on an inner tube or life ring type float and hang a pendulum
in it. As a wave goes by, the pendulum will always point to the center of
the float, even if the ring goes upside down inside the tube of a breaking
wave. There are videos of this in a wave tank. The pendulum can point
straight up. It's the same kind of motion that lets you sweep a glass of
water upside down without spilling.

The description of the roll over made perfect sense if the boat went up
inside the crest of a large breaking wave. The crew, hunkered down and
focused with tunnel vision on the compass and water's surface ahead were
inside the curl of the wave with mast pointed down and still thinking they
were in a normal attitude. Then, the mast hit the water changing the
physics as it dragged and stopped the wave acceleration that was creating an
artifical sense of "down". Down instantly shifted back towards the center
of the earth and the wave collapsed on top of them. This was a 60 foot
boat. Think of the scale of this event. Waves big enough to do this have
been confirmed on their route and time of year.

A wave of similar size rolled a ketch named Tz Hang (I think) in the same
part of the world as Barnes and Lange are sailing in. These mega breakers
may also be associated with as yet undiscovered sea mounts that are way, way
deeper than would be a concernt to ships as far as hitting them is concerned
but which can break the huge waves that can develop on these large oceans.

If you are thinking about the Smeetons with Tzu Hang, I seem to remember that
they pitch-poled rather than being rolled. Happened twice if I remember
correctly, then they made a third attempt some time later and made it ok.
Perhaps that is what this Barnes chap did, pitch-pole, that would account for
the damage.

Jan
"If you can't take a joke,you shouldn't have joined"

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