Aircraft pitch control systems and methods are disclosed. An aircraft pitch control system (28) comprises a movable horizontal stabilizer (24) and an elevator (26) movably coupled to the horizontal stabilizer. The elevator is electronically geared to the horizontal stabilizer.

A screw (20) assembly for an actuator (10) is described comprising: a screw (20); a nut (22) threaded on said screw (20), such that rotation of said screw (20) causes axial movement of said nut (22); a stop located at an end of said screw (20) and defining an axial limit of said nut (22); a first feature located on said nut (22); and a second feature located on said stop; wherein said first and second features are configured to cooperate with one another substantially upon contact of said nut (22) with said stop so as to indicate an amount of free movement between said nut (22) and said screw (20).

A screw (20) assembly for an actuator (10) is described comprising: a screw (20); a nut (22) threaded on said screw (20), such that rotation of said screw (20) causes axial movement of said nut (22); a stop located at an end of said screw (20) and defining an axial limit of said nut (22); a first feature located on said nut (22); and a second feature located on said stop; wherein said first and second features are configured to cooperate with one another substantially upon contact of said nut (22) with said stop so as to indicate an amount of free movement between said nut (22) and said screw (20).

An aircraft empennage includes a lower vertical member attached to a rear portion of a fuselage, and an upper stabilizer assembly connected to the lower vertical member by an articulating mount configured to allow movement of the upper stabilizer assembly relative to the lower vertical member to adjust pitch trim of the fuselage. The upper stabilizer assembly includes a V-shaped tail member having a pair of angled stabilizer portions, and each angled stabilizer portion has a trailing-edge ruddervator control surface. A rudder may be attached to a trailing edge of the lower vertical member.

An aircraft empennage includes a lower vertical member attached to a rear portion of a fuselage, and an upper stabilizer assembly connected to the lower vertical member by an articulating mount configured to allow movement of the upper stabilizer assembly relative to the lower vertical member to adjust pitch trim of the fuselage. The upper stabilizer assembly includes a V-shaped tail member having a pair of angled stabilizer portions, and each angled stabilizer portion has a trailing-edge ruddervator control surface. A rudder may be attached to a trailing edge of the lower vertical member.

An aircraft with rear mounted engines, comprising a vertical tail plane and a horizontal tail plane, in which the engines are mounted on top of the horizontal tail plane, such that the horizontal tail plane comprises an inner fixed part attached to the fuselage of the aircraft, the inner fixed part comprising an elevator, and two outer movable parts, each one of the outer movable parts being located at each side end of the horizontal tail plane which is furthest away from the fuselage of the aircraft, such that both the inner fixed part and the outer movable parts are at least partially subjected to a flow coming from the engines when the engines are in use.

An aircraft with rear mounted engines, comprising a vertical tail plane and a horizontal tail plane, in which the engines are mounted on top of the horizontal tail plane, such that the horizontal tail plane comprises an inner fixed part attached to the fuselage of the aircraft, the inner fixed part comprising an elevator, and two outer movable parts, each one of the outer movable parts being located at each side end of the horizontal tail plane which is furthest away from the fuselage of the aircraft, such that both the inner fixed part and the outer movable parts are at least partially subjected to a flow coming from the engines when the engines are in use.

A rotorcraft has a horizontal stabilizer movable about an axis of rotation and a horizontal stabilizer control system configured to control the horizontal stabilizer to at least one of move the rotorcraft into a minimum drag position, maintain the aircraft in a minimum drag position, efficiently achieve a maneuver, enter efficient autorotation, and maintain efficient autorotation.

A hybrid propulsion aircraft is described having a distributed electric propulsion system. The distributed electric propulsion system includes a turbo shaft engine that drives one or more generators through a gearbox. The generator provides AC power to a plurality of ducted fans (each being driven by an electric motor). The ducted fans may be integrated with the hybrid propulsion aircraft's wings. The wings can be pivotally attached to the fuselage, thereby allowing for vertical take-off and landing. The design of the hybrid propulsion aircraft mitigates undesirable transient behavior traditionally encountered during a transition from vertical flight to horizontal flight. Moreover, the hybrid propulsion aircraft offers a fast, constant-altitude transition, without requiring a climb or dive to transition. It also offers increased efficiency in both hover and forward flight versus other VTOL aircraft and a higher forward max speed than traditional rotorcraft.

A hybrid propulsion aircraft is described having a distributed electric propulsion system. The distributed electric propulsion system includes a turbo shaft engine that drives one or more generators through a gearbox. The generator provides AC power to a plurality of ducted fans (each being driven by an electric motor). The ducted fans may be integrated with the hybrid propulsion aircraft's wings. The wings can be pivotally attached to the fuselage, thereby allowing for vertical take-off and landing. The design of the hybrid propulsion aircraft mitigates undesirable transient behavior traditionally encountered during a transition from vertical flight to horizontal flight. Moreover, the hybrid propulsion aircraft offers a fast, constant-altitude transition, without requiring a climb or dive to transition. It also offers increased efficiency in both hover and forward flight versus other VTOL aircraft and a higher forward max speed than traditional rotorcraft.