An active flow control system for generating yaw control moments for an aircraft during hover flight. The system includes right and left yaw effectors disposed proximate the right and left wingtips of the wing. A pressurized air system includes a pressurized air source and a plurality of injectors operably associated with the right and left yaw effectors. Based upon which of the injectors is injecting pressurized air, the right and left yaw effectors generate no yaw control moment, generate a yaw right control moment or generate a yaw left control moment.

An aircraft can include a stacked propeller to generate lift during assent and descent. The stacked propeller includes a first propeller and a second propeller that co-rotate about an axis of rotation. In one embodiment, the blades are coupled to a rotor mast that contains an internal cavity. In one mode of operation, the first propeller and/or the second propeller can be stored in the internal cavity in order to reduce drag during flight. The aircraft can include one or more stacked propellers, such as a port propeller and a starboard propeller, which rotate in opposite directions during one or more modes of flight.

An aircraft can include a stacked propeller to generate lift during assent and descent. The stacked propeller includes a first propeller and a second propeller that co-rotate about an axis of rotation. In one embodiment, the blades are coupled to a rotor mast that contains an internal cavity. In one mode of operation, the first propeller and/or the second propeller can be stored in the internal cavity in order to reduce drag during flight. The aircraft can include one or more stacked propellers, such as a port propeller and a starboard propeller, which rotate in opposite directions during one or more modes of flight.

Methods and apparatus for mechanically driving components in a desired direction, such as in a moving craft. In one embodiment, the craft comprises a vertical or short takeoff and landing (VSTOL) aircraft comprising one or more rotating rings having airfoils disposed around a periphery thereof. In one variant, the one or more rings are driven by a multi-level drive apparatus having a plurality of angularly offset roller-based drive levels and a plurality of corresponding angularly offset driven members (e.g., rings), the plurality of driven members coupled to e.g., the at least one rotating ring. Advantageously, use of this arrangement provides enhanced reliability as well as opportunities for selective load balancing, and obviates comparatively heavy lubrication components such as seals and liquid lubricants, thereby also saving weight when applied to the host craft.

A propulsion system for an aircraft having a two stage contra-rotating fan system to generate thrust. The contra-rotating fan system is surrounded by an aerodynamic duct, having the power train within the duct.

A propulsion system for an aircraft having a two stage contra-rotating fan system to generate thrust. The contra-rotating fan system is surrounded by an aerodynamic duct, having the power train within the duct.

An aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a forward flight orientation. The aircraft has a blended wing body and includes an engine, a trinary lift fan system, a forced air bypass system and an exhaust system. The engine has a turboshaft mode and a turbofan mode. The lift fan system includes a plurality of ducted fans in a tandem lateral and forward orientation. In the VTOL orientation of the aircraft, the engine is in the turboshaft mode coupled to the lift fan system such that the engine provides rotational energy to the ducted fans generating the thrust-borne lift. In the forward flight orientation of the aircraft, the engine is in the turbofan mode coupled to the forced air bypass system such that bypass air combines with engine exhaust in the exhaust system to provide forward thrust generating the wing-borne lift.

An active flow control system for generating yaw control moments for an aircraft during forward flight. The system includes right and left yaw effectors disposed proximate the right and left wingtips of the wing. A pressurized air system includes a pressurized air source and a plurality of injectors operably associated with the right and left yaw effectors that influence the path of airflow above and below the yaw effectors. Based upon which of the injectors is injecting pressurized air, the right and left yaw effectors generate no yaw control moment, generate a yaw right control moment or generate a yaw left control moment.

A powertrain including an engine; a main drive shaft assembly; a primary clutch mechanism coupled to the engine and the a main drive shaft assembly, the primary clutch mechanism being operable to connect or disconnect the main drive shaft assembly and the engine; an axle shaft coupled transversely to the main drive shaft assembly; a secondary clutch mechanism having a driving member coupled to an end of the axle shaft; a drive wheel coupled to a first driven member of the secondary clutch mechanism; and an air propulsion unit coupled to a second driven member of the secondary clutch mechanism. The secondary clutch mechanism being operable to engage or disengage the first driven member and/or the second driven member to the driving member so as to connect or disconnect the drive wheel and/or the air propulsion unit to the axle shaft. A vehicle including the powertrain.

A powertrain including an engine; a main drive shaft assembly; a primary clutch mechanism coupled to the engine and the a main drive shaft assembly, the primary clutch mechanism being operable to connect or disconnect the main drive shaft assembly and the engine; an axle shaft coupled transversely to the main drive shaft assembly; a secondary clutch mechanism having a driving member coupled to an end of the axle shaft; a drive wheel coupled to a first driven member of the secondary clutch mechanism; and an air propulsion unit coupled to a second driven member of the secondary clutch mechanism. The secondary clutch mechanism being operable to engage or disengage the first driven member and/or the second driven member to the driving member so as to connect or disconnect the drive wheel and/or the air propulsion unit to the axle shaft. A vehicle including the powertrain.