Ah, yes, that is worth a try. A four inch PC fan or something a bit larger than that might work as well. right now, I figured I would just see what happens with the stuff Iallready have lying around.

UPDATE: I have finished making the duct for the lift fan. I made it out of a 1/8" plexiglass strip which I heated with a blow torch and formed into a cylinder. This was then cut in some areas so it would fit the front of the hovercraft. While that was being epoxied into place (with a water tight seal just in case the lift fan dies) I decided to work on the motor mount for the forward thrust motor. This was also made of plexiglass, 1/4", and supported by a peice of treated pine to handle the extra thrust generated by the bl motor. It was then painted blue to match the duct. While waiting for the paint to dry, I decided to reinforce the mounting of the duct, using gorilla glue to attach if to a pink unsulation foam base. This was shielded with 1/8" white abs sheet, and formed a sturdy base to mount the motor mount to.

The next steps will be to install the motor mount for the forward thrust motor and test all systems. Afterwards, I will start paying attention to the body of the hovercraft and its water-going characteristics.