Come on.

To be effective, a tunnel thruster needs to be 2 - 4 diameters below
the surface. A lot of boats are less but their thrusters are usually
toys that don't have enough thrust when you really need the help.
There's only so much thrust you can generate with a certain diameter.

Put these factors together with a boat shallow enough that it's going
to be able to go fast enough to lift its bow very much and lifting the
thruster clear of the water to reduce drag becomes petty improbable.

How do you like these thrusters?

http://home.maine.rr.com/rlma/D124-7.PDF

--

Roger Long



"Capt John" wrote in message
oups.com...

Tamaroak wrote:
I'm thinking of putting a bow thruster in a 36" trawler. Has anyone
read
any studies or done any research on what this hole and the
subsequent
tunnel might do to its fuel economy?

Capt. Jeff

Jeff

Bow thrusters are supposed to be mounted such that, at crusing
speed,
the unit is out of the water. This may not be practical on some very
slow moving boats that do not sit bow high at cruse.

John