first things first
bow thrusters will do no effect if your boat has speed. thay'r used to turn on spot and/ or pull. bow thrusters can be connected with automated system that is used instead of anchor. the system will hold position with the help of GPS, bow thrusters and main engine.
your boat isn't a pilot, it won't pull, so you don't need a lot of HP. cca 10, 15hp max. it depends on your boat length of course.
thrusters can be propelled by hydraulics or electricity.
probably the best is to mount on your bow an external bow thruster. it is electric and comes out the water when it is not used. i saw also a homemade option -> an outboard electric motor mounted on the side. electric because of light weight.
Last edited by Karletto; 09-14-2008 at 02:23 PM.