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JAXAshby
 
Posts: n/a
Default Thrust vectoring

sorry, Dan. don't try to noodle this one out. It is a fact of physics that
you can NOT control using rudder by *pulling* water over it. you MUST push.

lay people often don't that know, for intuitively it doesn't seem "right". but
jeffies has in the past claimed specifically not to be a layperson regarding
physics.

Sorry Jax, sometimes you get it right, but this time your habit of
stating absolutes where not appropriate is showing again. The
underwater lawn sprinkler is an imperfect model for the mechanics of a
boat's prop and rudder. Now, a prop in reverse creates very little
water movement past the rudder compared to one in forward, but very
little is not the same as none. As long as there is water being moving
past and deflected by the rudder there will be some lateral force
generated. Not much in this case, but some. This can be readily
demonstrated as another poster pointed out.

JAXAshby wrote:
The exercise was
repeated in reverse hanging off a bow line, proving (contrary to jaxie's
claim)
the affect works in reverse,



geezus kriste, jeffies, you claim to have a degree in physics and have

NEVER --
to this moment -- heard of classic "under water lawn sprinkler" paradox

that
ALL physics students learn.

Get your wife to explain it to you. It is impossible to steer by *pulling*
water over a rudder with a prop. Can't be done, except when under the
influence of hard drugs.



--
Dan Best - (707) 431-1662, Healdsburg, CA 95448
B-2/75 1977-1979
Tayana 37 #192, "Tricia Jean"
http://rangerbest.home.comcast.net/TriciaJean.JPG