High-speed craft have been known to lose stability while underway even though they possess adequate static stability. Dynamic instabilities have been reported in roll, pitch , and yaw, and include porpoising, chine walking, loss in running trim (diving), bow steering, progressive heeling to port or starboard, or a combination of motions.

Ride Control Systems (RCS) are routinely fitted to high-speed vessels. RCS offer improvements in performance and ride quality for such vessels.

Progress in the performance of advanced craft and the merits of various limit forms differ with respect to the technological maturity of each concept. Full-scale, calm water trial data of speed and power for known displacement transport efficiency is used to compare the optimum performance of several hull forms such as planning, round bilge, stepped, catamaran and SES.

Whether steering a straight course or maneuvering, a boat operator must be in control of the boat’s direction. Outboards, outdrives, and some waterjets and surface drives generate steering forces by turning the propulsion unit.