Abstract: The present invention relates to a hydrofoil system for a waterborne vessel, the hydrofoil system comprising a controller, a foil for engagement with the waterborne vessel, the foil comprising a plurality of adjustment members operable to vary the lift characteristics of the waterborne vessel, a propeller, an engine and gearbox located adjacent the foil and operable/in mechanical communication with the propeller, a plurality of sensors in electrical communication with the controller, each sensor configured to monitor flight parameters of the waterborne vessel and generate measured flight parameter data, wherein the controller is in communication with the adjustment members, the engine and the sensors and wherein the controller is configured to receive measured flight parameter data from the sensors and to control the operation of the engine and the position of the adjustment members in dependence upon the received measured flight parameter data.