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Doug Dotson
 
Posts: n/a
Default push vs pull vis a vis rudders

This all fits with my expierence. In reverse, propwalk is dominant
until some way is acheived. Then rudder control is possible.

Doug
s/v Callista

"JAXAshby" wrote in message
...
actually, there is a difference. If you put the tranny in forward and

push the
throttle forward you can turn the boat one way or the other. Because of

this,
some people believe you can do the same in reverse. You can't.

In addition, I have met people who had trouble backing up their boats who

in
some cases were told that if they were to spend $XX,XXX's by moving the

prop
closer to the rudder they would get better turning ability on the boat.

They
would not.

Indeed, in a recent thread "Thrust Vectoring" many people insisted that

pulling
water over a rudder would turn a boat. When I said it would not, several
people wanted to argue about it (including one dumb cluck who claims to

have a
degree in physics, really dumb because this problem in physics is a

classic
taught to early semester students). A couple people asked for an

explanation
as why pulling water over a rudder had no effect and all, and I said I

would
write one up today.

If one wants to steer by rudder backing up, one needs to start the boat

moving
backwards slowly, otherwise prop walk will twist the boat sideways. Start
slowly until the boat is moving and the rudder becomes effective,

depending on
how much the boat is moving through the water.

Net, net, you wanna steer with a rudder backing up, prop forward of the

rudder,
you MUST be moving.


Not sure what the point of steering if you are not moving would be?

Forward
or reverse. If you are not moving, steering has no meaning.

Doug
s/v Callista