Jacklines for power boats
Don White wrote:
"HK" wrote in message
...
Frogwatch wrote:
On Mar 4, 10:13 am, wrote:
On Mar 4, 6:37 am, HK wrote:
Vic Smith wrote:
On Tue, 03 Mar 2009 23:46:42 -0500, Wayne.B
wrote:
On Tue, 3 Mar 2009 20:18:50 -0800 (PST), Frogwatch
wrote:
Any reasonable thoughts on strategies for such conditions to avoid
turning over? Any thoughts on design of a boat to minimize such?
Naval architects have theorized, confirmed by testing, that *any*
boat
can be capsized by a wave of the right size and shape. There are
screening formulas that you can search for, but as an approximation,
a
steep breaking wave with a height of slightly more than half a boat's
maximum width (beam), can cause a capsize. Large Bertram
sportfishing boats have been capsized, 120 ft Alaskan fishing boats
have been capsized, heavily ballasted keel boats have been capsized,
and many, many others. In other words no boat can be considered
totally safe in extreme conditions, and small boats become unsafe
very
quickly. The coast guard has rescue boats that are designed to
survive capsize by virtue of rugged water tight design, heavy
ballasting, and carefully designed mechanical systems. They can
survive capsize but can not totally prevent it.
There was actually the possibility of righting that Everglades if they
had been prepared for that. No reason they should be, but with 4
strong heavy guys and the right technique and gear it was a
possibility.
Then they'd face the issue of bailing without rolling it again in
heavy seas.
I read once of a guy who got pretty good at righting his bigger racing
multi-hull with a little powerboat assistance.
All Monday morning quarterbacking now. What a shame they couldn't
all stay with that boat.
--Vic
I don't see how it would be possible. A 21' boat like that upside
weighs
more than the strength of four guys NOT standing on solid ground to
turn
it over. How could you get leverage?- Hide quoted text -
- Show quoted text -
Wow, for someone who claimed to have a degree in Mechanical
Engineering, you sure don't understand vector mechanics very well.
My 20' Tolman weighs roughly 1200 lbs, righting her might be possible
in calm water. Stand on lines attached from the bow to middle to
stern cleat to sink one side more. Run a line over the hull to the
middle cleat and have somebody hold onto that standing against the
hull leaning backwards and I bet she'd flip over.
However, I agree, righting is a poor survival strategy because of the
poor likelyhood of doing it and keeping her upright until she is
bailed.
So, what we need are better survival strategies assuming she stays
bottom up. I think the jackline idea so they can at least get partly
out of the water along with the trash bag idea would help a lot. What
amazes me is that it seemed that none of the jackets had strobes. A
strobe for a jacket costs maybe $12.00,, cheap compared to anything
else.
I think it would be fun to dump Loogy in the water with a heavy 21' center
console boat and engine and gear, turned turtle, and a rope,
and in deep water with significant waves. It would be a worthy
demonstration of Loogy's boating abilities and his understanding of vector
mechanics.
He'd simply katate chop the boat up into managable bits and then re-assemble
after righting each individually.
You are dumber than ever, lemming.
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