Hull speed can be exceeded. The caveat is that to do so the horsepower needs increase at a faster rate per increased speed than when under the hull speed. Hull speed is not a magic number, it is the result of a formula that was derived long time ago when boats were made of wood and most had a similar hull shape. The formula for hull speed in knots = The Square Root of the length of the waterline in feet times a constant of 1.34. This constant of 1.34 is a trash number developed to represent the ratio of speed to the square root of the wetted length. It just so happens that back then most hulls were shaped and constructed similarly and would fit this ratio. This ratio of speed to the square root of the length varies widely in today's boats. I agree with your concept of speed that real speed is the speed over the water and not the speed over the bottom but many boats can go faster than the formula would today indicate and these boats would react differently to the addition of increased horsepower. Many times it is not current but wind that may slow the forward progress and in those cases a stronger engine will do better.
Totally agree. My boat is a motor/sailer with a semi planing hull. It can take up to a 40hp outboard, and pull a skier.
It's pretty funny, the looks we get, when pulling a tube on a masted boat! (I have a 25hp, on mine)
As with any compromise, though, my boat actually sails better, than it motors. There's other hybrids that motor better than sail.
None of the hybrids excel in either mode though.
That being said, I prefer the hybrids. I live in an area with no wind, in the summer, but plenty in the spring and fall. I enjoy sailing more than motoring, but when there's no wind, I can still enjoy the water, and go reasonably fast under power. Sometimes, I'm feeling lazy, and just want to hit the water for a quick bit. So no rigging or mast raising..just power up and go.
