In a message dated 3/26/2010 6:23:18 P.M. Pacific Daylight Time,
vbra676539@aol.com writes:
Hi Vance. I understand how a big rudder helps with steering, whether the
prop is turning or not, as long as there's some travel. With a big rudder, does
that make the sub turn into the current if there is some cross current ? You
know, like a weather vane.
Dean's sub has a big rudder and I was wondering how it would affect the
sub's travel.
The big "fin" on the back of my sub may act something like a rudder in a
cross current.
I needed to add the fin because early scale model testing in moving
water produced some "wobbling" and by adding the vertical fin it stopped. Now, I
don't have any means to equate scale model speed in the pool to real life speed
for the full size sub, but the water speed in the pool was probably a lot faster
than this little boat will ever go, so maybe the fin wasn't really
necessary for the expected slow speed the sub will actually go. If I had to make
a wild guess, I'd say the pool speed was a scaled down 30 knots or so.
Frank D.
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