RE: Qestions from a Newbie
to help keep it stable, use a prop that is 2-3 inches shorter than the width of the hull.
others that i have seen with a sim sized motor had hulls smaller than your proposed size. i would look on youtube and the RCU members gallery for gasser airboats. check out the over-all size, and ask what the prop size/pitch were. i cant give you numbers, iv only built a electric version.