[hpv-boats] changing drive direction

[Ian Cassell]

Mark
         Problem I see with using a fan belt is the
slippage. When tensioned enough to stop the
belt from slipping as the prop spins the friction 
losses would be very high. That is most of your
effort goes into turning the cranks and not a lot
of that power turning the prop. Belts such as the
timimg belts used in cars may be a better alternative
as they would give a positive grip without a lot
of friction to overcome.

Ian