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In a message dated 9/13/2009 2:57:55 P.M. Pacific Daylight Time,
glenbrown@vodamail.co.za writes:
.Without proper research any wing design could make the boat uncontrollable at slow speeds.This Is only my opinion I could be wrong. That's why I chose the combination of control surface ( dive plane and
rudder) with the motors.
At the slow speeds our subs have we need to "push" the water in the
direction we want rather than relying on prop wash over a control surface. It's
very difficult to get vectored thrust if your main motor is inside the sub with
a shaft and all, but using just the Minnkotas is easy. Basically the rudder
linkage pivots the motor too so no extra stuff.
The down side to this is the relative low power available. With an inboard
motor it can be as large as you have room and/or power for. Dean's sub has 10
horse or so doesn't it ?
With the 4 motors I'm using it adds up to 10 horse at full power but my
guess is that I'd probably "smoke" something if I ran all 4 wide open.
Fortunately these little subs don't need to go very fast. If we're looking at
stuff or near any rocks it's not safe to go fast anyway.
I'm gonna try it wide open sooner or later just to see how fast it
could go but that can't be good for the batteries or electrical system in
general. Those motors pull 46 amps at full speed. If I multiply that by
4.......something's gonna blow!
Frank D.
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