performance

[jollyricard]

excellent stability of planing hulls? how to achieve it?the best trim angle how to maintain it at different speeds?

[tom28571]

Given a particular planing hull and loading, the boat will assume the equilibrium trim angle necessary to generate the dynamic lift required to support the boat at that speed. Lower the speed and trim angle increases, raise the speed and trim angle decreases. Increase the load, without changing balance, the trim angle will increase and vice-versa.

Sure, its more complicated than that but that is the basic principle at work. If you want some dynamic lift, some trim angle must be taken. Zero trim angle generates zero lift.

Trim angle can be forced, as in step hulls or changed with trim tabs, etc. Most designers say that a trim angle of 4 to 5 degrees in a monohull planing boat gives a minimum sum of wavemaking and frictional drag.