Hi folks.
Check out this video of a planing production catamaran from 1980. It performs well here in 15 knots of wind despite a poorly cut sail. www.mckeewildthings.com/video/itzacatbig.mov
you will need the latest version of quicktime.It's 40mb
There is a smaller 15mb version at www.mckeewildthings.com/video/itzacatsml.mov
The hull widths and planforms were chosen based on calculations of planing efficiency, not because they resemble a sailboard. Note than the hulls are canted at an angle to each other so that the leeward hull is at an effective planing angle when the windward hull is slightly lifted from the water. A later version was scaled up to 17 feet long and had two steps to reduce wetted surface, so that it's wetted surface when planing was much less than the craft in the video, but with a tornado sized rig.