Thrust vectoring
Shen44 wrote in message
...
OK, think I see what you're saying.
First off, I used to run a 65 foot boat with a similar
configuration and
remember a beautiful old 45' ketch with the same thing ... both
had large
degrees of "propwalk".
Interesting. Some of the older boats had engines added later, of
course, and sensibly had prop shafts installed with an offset so
you could remove the shaft without taking the rudder off. That
changed the prop wallk picture a bit!
Secondly, I think we may have different views of what is the
major cause of
prop walk (I attribute it to the pitch of the blades pulling to
a greater
degree on the "down stroke" side of the revolution, than the
"upstroke side").
OK. The only certainty about prop walk is that it must be caused
by the prop in reverse squirting more water to one side of the
boat than the other. We could discuss the mechanism for ages -
but there wouldn't be much practical use to that unless we were
designers!
BG Why would I want to design "propwalk" out? "Propwalk" is
my friend!
Especially pulling the stern in as you come alongside.... bit of
a sod when it's the wrong side though.
JimB
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