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In article ,
says...
On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said:
A freewheeling propeller creates more drag than a locked on.. Just
consider a helicopter. Engine out and rotors freewheeling, the aircraft
will go down safely. Rotors locked and it drops like a stone.
Bad analogy. In a helicopter when the rotors are freewheeling after the
engine dies they're still rotating in a direction that generates lift.
I just have to ask. In what way is it a bad analogy?
Possibly you are thinking the freewheeling prop would somehow generate
some forward motion. Not likely or you would have a perpetual motion
machine. Stop the external power, in the case of a sail boat, the wind,
to a freewheeling prop and, as with the auto rotating helicopter having
it's fall slowed, the prop just slows you down faster. Neither generates
more energy, they consume it and thus slow the downward/forward motion
of what ever they are attached to. Every action has..........etc.
Personally I figure, locked or freewheeling, the difference in the
amount of drag caused by a kicker's prop is going to be so small as to
be a total non issue unless you are into times in parts of a second in
which case you pull the damn thing out of the water anyway.
--
Mike G.
Heirloom Woods
www.heirloom-woods.net
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