Jon and Blue you should get together and pool your resources as 5hp will lift a small craft and another 5hp would give you some thrust but not a lot it should move on a smooth surface like concrete etc. I think you are both heading down the same bad path and are going to finish up with a lot of wasted time and you will be very dissopointed with the results.There are some very cheap plans on the Universal Hovercraft site for a single seater like 12 or plans for a 10x5 craft also for 12 a small price to pay for something that has been proven to work although I think you may find the speeds a little exaggerated they may mean KMH instead of MPH lol.