sheograth

This is for a drag boat but I'm asking here since the boat folks have limited DF experience. I'm looking for something to mate to a 100+ CC gas airplane engine.

f16man

You want to use a aircraft ducted fan unit on a boat hull???? how are you going to turn it, maybe like an everglades style boat? A 100 CC engine will not turn the high rpm that a df needs to make thrust , a large prop would be a better choice for that engine.

wind junkie

My Feedback: (1)

yea, I don't quite understand either.

Large gas motors are all about torque and big diameter props. Fans are handicapped by having less diameter and therefore need to spin much faster to move enough air to do the job.

I've never heard of a gearbox for a large gas motor to give you more RPM. A big electric motor would be a better choice I think. Stop over to RC groups and look over what the current crop of electric ducted fan guys are doing. It takes a lot of money to move a lot of air with a ducted fan, but these guys sure seem to be having fun.

Detour747

Check this thing out its electric but can push quit a bit: http://www.ductedfans.com/Turbo_Fan_...edfanscom.html .

sheograth

Ok, that all makes sense then. It's either an electric ducted fan or a gas engine with a prop.

And yeah in terms of turning it would be like a swamp boat.