Planning a Hover Craft

I'm planning to make a remote controlled hover craft, one thats big enough someone can still sit inside.. aprox. 4'X3'.

I know the baisic idea and everything but i still have a couple questions i cant find any answers to.

1) I cant find a site that has detailed instructions for stitching a air skirt. nothing fancy like fingers just a bell skirt.

2) Does the hull need to come over the top lip of the skirt or rest within it?

3)Where can i find a fan that can withstand the forces of a lawnmower engine ( i dont want anyone dead)

4) a cheap way to secure the skirt? ( ive read velcro works well? )

5) what can i use to house the fan blades incase of a failure and one blade comes loose? (it needs to be lightweight)

thanks alot guys, if you have any questions or comments please let me know!