I would go for a big, honkin', fixed, six-bladed prop in a tunnel,
designed as a system and driven by hydraulics. A streamlined
door on each end of the drive could be closed when under sail
to minimize drag.

For maximum thrust in reverse without a tendency to side slip
one needs tunnel drive. It works for most of the big tugs on
the Western Rivers it should do the job on a relatively lightweight
yacht.

CN


"Bart Senior" wrote in message ...
2 points

After hitting the lottery for big bucks, you have nearly completed
your 150' new sailing mega yacht. Included on your new toy are both a
bow and stern thrusters--for side-to-side control..

What sort of prop would you want if you were concerned about precise
speed control, and being able to back down nearly instantaneously?

Money is, of course not a concern.

Capt. Neal® wrote:
I would go for a big, honkin', fixed, six-bladed prop in a tunnel,
designed as a system and driven by hydraulics. A streamlined
door on each end of the drive could be closed when under sail
to minimize drag.

For maximum thrust in reverse without a tendency to side slip
one needs tunnel drive. It works for most of the big tugs on
the Western Rivers it should do the job on a relatively lightweight
yacht.

CN

I think you'll find that what most tugs use are Kort Nozzles, rather
than tunnel drive. The idea being to improve bollard pull, rather than
reduce prop walk (prop walk is your friend if you know how to use it).

otn