Not a whole lot is required to move that much weight.
However, moving it at the speed you want, or getting it up to that speed as
quickly as you want may be an issue.

Toesup built "Mustang Sally" with a 3:1 drive ratio and runs a 3.75" propeller on
a 10lb boat measuring 18"x8"(a springer) hull. The boat can produce about 4lbs of thrust.

http://www.rcgroups.com/forums/showp...postcount=1980

I run the same size boat, "Ryoko", weighing 8lbs, direct drive running a 1.75" propeller.

Both boats can push 900-1200 lbs of weight.

Some of the heavy cruisers we run weigh up to 100-120 lbs. They are run with two
Pittman 12-24v motors, maybe 2" propellers and they travel a brisk walking pace.

None of these are jet drives, but the thrust and RPM are well below what you seem
to be specifying, and they all move at a reasonable pace.



Mustang Sally and Scoot
[youtube]http://www.youtube.com/watch?v=oO_SYiPUvxo[/youtube]

Ryoko and the SDM tug
[youtube]http://www.youtube.com/watch?v=83z4y9UV4QA[/youtube]


Mustang Sally putting pumpking in motion.
Super Springer "Scoot" with SDM tug in the background
Stock Springer "Ryoko" pushing pumpkins.
Ryoko and the SDM tug wrangling a large gourd.