Abstract: A parking tail rotor for a rotary wing aircraft stops rotating at a high forward aircraft speed when aircraft control surfaces have adequate control authority to balance main rotor torque without the rotating tail rotor. When stopped, the blades of the parking tail rotor move due to the force of the relative wind to a parked position in which the span of the blades extend in the aft direction, reducing air resistance to the forward motion of the aircraft.

Abstract: A supplemental wing for a rotary wing aircraft rotates about a pitch axis between a forward flight position and a hover position. The supplemental wing generates lift and generates both positive and negative pitching moments that balance and that may passively rotate the supplemental wing to an equilibrium position. The supplemental wing may use power assist to overcome friction to move to the equilibrium position. The lift generated by the supplemental wing reduces at high forward speeds to preserve main rotor control authority. The supplemental wing rotates to avoid aft translation when in the hover position. The supplemental wing may be retrofitted to existing helicopters and flown using existing helicopter controls without pilot re-training.

Abstract: A floating offshore wind turbine includes a rotor and a generator turned by the rotor. An elongated buoyant body supports a tower that supports the generator and rotor. The buoyant body or the tower may support aerodynamic features to counteract heeling forces or to steer the floating wind turbine as it swings on its anchor line. The floating offshore wind turbine may be configured to move the anchor line force vector to counteract heeling forces. A control system may control the aerodynamic features and the movement of the anchor line force vector.