Rope/Chain Rode calculations
"Jeff" wrote in message
...
Actually, I think you overstate the amount of "spring" a chain
rode provides. When there is still chain on the bottom, there
is spring in the system from lifting that chain, but when fully
lifted into the classic "catenary" shape, there is very little
left.
I completely agree, Jeff.
The model I offered was, as you probably realised, the 'lift off
the ground' model. I presented the best possible case for the
catenary, to show that, even then, nylon still wins as a shock
absorber.
The catenary myth is an article of faith among many charter
sailors (and those who brief them) in the Mediterranean. The
common mooring there is bows or stern to, when the rode is usually
stretched off the ground already. I've had many a quayside
discussion (complete with bits of string and jugs of beer)
explaining why the surge from a ferry caused an anchor to snatch
out. Logic doesn't always win when you challenge an article of
faith though, even after the bribe of a beer or two, unless it is
a blindingly clear demonstration!
JimB
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