On Sat, 29 Jan 2011 19:50:52 +0700, Bruce
wrote:

Sorry, but I didn't understand even 1/2 of this. Maybe one should not
go sailing if you can't deal with the issues that come up, short of
being run over by a tanker or something?

Sounds pretty simple. Can you deal with a tsunami arrives with no
warning and kills some 5,000 people in your immediate area? A 60 MPH
squall that hits you at night?

Of course not. A couple of things occur to me. First, I thought a
tsunami was only dangerous near land. If that's the case, then how
could it do damage to a boat that's sailing offshore? Second, it seems
like you should be able to handle high winds. Wouldn't you be prepared
for that? Why are you sleeping when there's a storm going on?

snipped.

A tsunami, or any other wave is simply water in motion. Depending on
the length and speed of the wave, the amount of vertical movement is
generally dependant on the depth of the water it is moving in. So you
are correct to say that in deep water they don't have much height, but
simply saying "off shore" isn't a sufficient description as you can be
quite a distance "off shore" and still have relatively shallow water.
in among the S.W. Thai waters, where the Tsunami did the most damage,
waters are generally less then 100 ft.

A "Sumatra", which might be called a line squall in other parts of the
world, is a rather brisk wind that travels fairly rapidly and if at
night generally is bit of a shock.

In the case I mentioned I was sailing north along the E. Coast of
Malaysia on a fine moonlit night with about 5 K. wind. Then, within
only a few minutes it was blowing 60 miles an hour for about an hour.

As in the case of the Tsunami, it has been stated that it is the worst
natural disaster in Thai history. A bit hard to plan for. Squalls
occur, frequently with no warning, certainly not something you can
specifically prepare for other then in a general way that you know it
might blow a bit.

And I don't remember saying I was asleep when the squall hit.

Not saying you were asleep. Sorry if I implied that.

As to water depth, in the middle of the ocean there's no dispute
right? No damage. So, you're claim is that in 100 ft of water, the
violence would be great?

Actually in my case it was the trough that was the most noticeable. I
was sitting on the cockpit combing and watching a catamaran and a mono
hull, both headed toward Phi Phi and discussing, with my wife, which
one would get there first when suddenly the horizon was only a very
short distance away, perhaps 50 - 100 meters. By the time I could say,
"What the...." the horizon was back to normal and we saw the wave hit
an island some 3 miles east of us.

So, nothing much happened on your boat. You noticed it, but that was
about it.

I recall hearing? reading? about people in
their sailboat in the harbor who rode it out by getting going, then
rescued a bunch of people. Seems to me you're safer moving and away
from the marina, which was my point.

Yes, we had some friends anchored in a bay on the S.W. side of Phuket
and when the water suddenly went away, as they described it, they, a
bloke and his wife, started the engine and knocked the lock off the
anchor winch and ran the chain overboard and headed for the ocean.
They said that they got far enough off shore by the time the crest got
there that they just bounced up and down a bit.

Sounds like they were prepared and did the right thing...?

You're saying you can't see a squall coming? You can't be prepared to
deal with it? It just happens and there's nothing that can be done?
Seems wrong to me....

I didn't say that you can't see a squall coming, in daylight but after
dark they are not easy to see. After all the squall may be advancing
at 60 MPH.

Now if you are sailing along with, say one reef pulled in, with the
wind blowing from the side of the boat - what is called a reach - then
from the time you see the squall is approaching until it gets to you
can be a very short time, and if it is after dark with only a light
wind blowing it may hit before you even know it is coming.

In the situation I described it will knock your boat down - lay it
over on its side - which by itself is not particularly hazardous in a
well found sloop (single masted boat), but will certainly make you sit
up and take notice.

Well, hang on a sec... I don't know what reef pulled in means, but
when the wind blows against the sail, the boat leans over... knocks
down? Ok. Then what? It comes back up or does it keep going? What
happens if you release all the sails? If it happens at night, then ok,
you got hit the first time, but then.... ?

We released all the ropes when we brought them down at the end of the
day... the sails and ropes just flapped around a lot and the boat
stopped moving.

In the book the Perfect Storm, the sailboat seems to take it long
enough for the people to be rescued, and it seems like the winds in
that storm are much higher than in a squall.