Automatic Trim Optimisation System (ATOS) is an embedded functional option to the basic Humphree Interceptor System. This additional function offers automatic and semi-automatic optimisation of vessels’ running trim for faster acceleration, higher speed, increased range and safer and smoother ride. The ATOS is featuring adaptive logic capable of adjusting to changing loads and sea conditions, as well as weighing in the operator’s manual input. In “automatic” mode ATOS automatically controls the interceptors by moving their blades in an incremental manner and simultaneously recording the resulting ship speed registered on a dedicated GPS receiver. When the maximum speed at a given engine output is attained, the most favourable position of the interceptor blades is established and the vessel thereby runs at optimum attitude. In “semi-automatic” mode ATOS controls the interceptor blade by following a programmed optimal relation between ship speed and blade position.