Abstract: A fixed-wing or rotary-wing aircraft has a tail boom that contains a fuel tank. The fuel tank is configured to contain pressurized hydrogen. The pressurized hydrogen fuels a fuel cell stack to generate electricity to rotate one or more rotors or propellers. The fuel tank may define the structure of the tail boom and may support the empennage, tail rotor, propeller, convertible thruster, ducted fan or vectored thruster and associated drive systems with respect to the fuselage. The aircraft has adequate control authority for sustained coordinated flight when the fuel tank is filled with pressurized hydrogen and when the fuel tank is drained of pressurized hydrogen. The same aircraft may not have adequate control authority for coordinated flight if fuel tank was filled with a conventional liquid fuel.

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 removable battery to provide motive power for an aircraft includes a battery frame and removable, interchangeable battery modules. Each of the battery modules defines module common space through which liquid heat transfer fluid flows during charging of the battery when the battery is removed from the aircraft and through which air as a heat transfer fluid flows during discharge of the battery, as during flight. The module common space also defines a combustion conduit to convey heated air and products of combustion safely outside the battery in the event of a cell fire during flight. The removable battery frame is a structural component of the aircraft.

Abstract: A foldable aerial vehicle may take the form of a flying wing. The flying wing includes port and starboard wings having port and starboard root and tip portions. The port and starboard root and tip portions are hinged one to another so that the span axes of all of the root and tip portions are parallel in the stowed condition and so that the tip portions are separated by the root portions in the deployed condition to define the flying wing. The wings are not symmetrical about the longitudinal axis of the vehicle, with the span axes of the root and tip portions being stepped from one wing tip to the other. Folding winglets are disposed on opposing wing tips, with the higher winglet extending in an upward direction and the lower winglet extending in the downward direction.

Abstract: A compound aircraft includes a convertible thruster that pivots between an anti-torque position, a forward thrust position, and intermediate positions. A pilot has two inceptors to control thruster rotor pitch in the anti-torque and forward thrust positions. A mixer mechanically blends the signals from the two inceptors during transition between the anti-torque and forward thrust positions. A transfer rod coaxial with the pivot axis of the convertible thruster conveys convertible thruster pitch commands from the pilot to a pitch control actuator. The pitch control actuator may be located partially within the rotor of an electric motor that rotates the convertible thruster rotor. The electric motor and pitch control actuator are unitary. Both the electric motor and pitch control actuator pivot with the convertible thruster. The pitch actuator output shaft is coaxial to and disposed within a hollow electric motor output shaft.

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.

Abstract: The Invention is a self-rescue system for an aircraft. The aircraft may be a flight module, a mission module, or a combined flight module and mission module of a modular and morphable air vehicle, or may be any other aircraft. The self-rescue system is modular and interchangeable and provides selectable capability to protect the flight module, the mission module, and any crew or cargo of the mission module in the event that the flight module or mission module suffers mishap or system failure during flight.

Abstract: A ducted fan for an aircraft or other vehicle includes aerodynamic features to selectably move the thrust vector of the ducted fan from the axis of rotation of the ducted fan, providing additional and redundant control authority to a control system. The control system may apply the aerodynamic features asymmetrically about the circumference of the duct and may apply the aerodynamic features differentially among a plurality of ducted fans. The aerodynamic features may include a morphing leading edge portion, an air dam, vanes and trailing edge control surfaces.

Abstract: A personal air vehicle may feature an air module that may be attached to a ground module. The air module may be equipped with exit vanes or vectored engine exhaust to provide redundant control effectors to the cyclic or collective pitch of at least one rotary wing under the control of a control system.

Abstract: A personal air vehicle may feature an air module that may be attached to a ground module. The air module may be equipped with exit vanes or vectored engine exhaust to provide redundant control effectors to the cyclic or collective pitch of at least one rotary wing under the control of a control system.

Abstract: An air module may be attached to a ground module. The air module may be equipped with a center of gravity effector to change the relative locations and hence the center of gravity of the air and ground modules when the modules are attached. The center of gravity effector may be active or passive or a combination of active and passive. The center of gravity effector may be combined with a center of lift effector to change the relative locations of the center of gravity and center of lift.

Abstract: An air module may be attached to a ground module. The air module may be equipped with a center of gravity effector to change the relative locations and hence the center of gravity of the air and ground modules when the modules are attached. The center of gravity effector may be active or passive or a combination of active and passive. The center of gravity effector may be combined with a center of lift effector to change the relative locations of the center of gravity and center of lift.

Abstract: An unmanned air module includes one or more rotors, engines, a transmission and avionics. Any of several different ground modules may be attached to the air module. The air module may fly with and without the ground module attached. The ground module may be manned. The air module may have two rotors, which may be ducted fans. The air module may include a parachute, an airbag and landing gear.

Abstract: An unmanned air module includes one or more rotors, engines, a transmission and avionics. Any of several different ground modules may be attached to the air module. The air module may fly with and without the ground module attached. The ground module may be manned. The air module may have two rotors, which may be ducted fans. The air module may include a parachute, an airbag and landing gear.

Abstract: An unmanned air module includes one or more rotors, engines, a transmission and avionics. Any of several different ground modules may be attached to the air module. The air module may fly with and without the ground module attached. The ground module may be a vehicle ground module and may be manned. The vehicle ground module may transport the attached air module across the ground. The air module may have two rotors, which may be ducted fans.

Abstract: An unmanned air module includes one or more rotors, engines, a transmission and avionics. Any of several different ground modules may be attached to the air module. The air module may fly with and without the ground module attached. The ground module may be a vehicle ground module and may be manned. The vehicle ground module may transport the attached air module across the ground. The air module may have two rotors, which may be ducted fans.

Abstract: An unmanned air module includes one or more rotors, engines, a transmission and avionics. Any of several different ground modules may be attached to the air module. The air module may fly with and without the ground module attached. The ground module may be a vehicle ground module and may be manned. The vehicle ground module may transport the attached air module across the ground. The air module may have two rotors, which may be ducted fans, and three different configurations: a tandem rotor configuration, a side-by-side configuration, and a tilted-rotor configuration.

Abstract: A wind turbine rotor blade and a wind turbine incorporating the rotor blade include a first and second composite skin. A first and a second spar pultrusion having a base and a plurality of integral ribs generally normal to base are attached to the inside surface of the first and second composite skins and extend the span of the rotor blade. At least one shear web connects a rib of the first spar pultrusion to a corresponding rib of the second spar pultrusion. The width of the spar pultrusions decreases in a step-wise fashion along the span of the rotor blade from the root to the tip. The leading or trailing edge of the rotor blade may be selectably opened for inspection and repair.

Abstract: A compound aircraft features variable incidence wings, a thruster, a rotor and a clutch connecting the engines to the rotor. Upon reaching a suitable forward speed, the control system of the compound aircraft unloads the rotor and disengages the clutch, disconnecting the rotor from the engines. The control system configures the cyclic and collective pitch effectors to cause the rotor to autorotate. The control system selects an autorotation rotational speed that is adequately rapid to prevent excessive deformation of the rotor blades due to aerodynamic forces acting on the blade and that is adequately slow to prevent excessive compressibility effects.