RE: 41 Falcon cat build
The Octura 1475 is a 2 blade if there is a good chop or wind I usually trim in a bit. You can also put a strip of balsa that is 1/4" wide 1/8" thick and the lenght is 75% of the distantace between the sponsons up front. Position the wood in the center and 1.5-2" from the front on the bottom of the hull....this will still let the hull pack air and helps prevent blow over. Once you have the lenght soak the balsa in water so it will flex....then tape it to the hul so it will have the curve from left to right....paint it your color so it will be sealed and bond it as described above.