A method and system for attaching a vertical stabilizer to an aircraft fuselage using a clevis system is disclosed. A composite skin is installed over the aircraft fuselage. The composite skin has apertures for receiving a plurality of clevises in a clevis system. The plurality of clevises is inserted through the apertures in the composite skin. Each of the plurality of clevises is secured to a frame member in the aircraft fuselage. The vertical stabilizer has a multi-spar box connected with a base rib assembly having a plurality of lugs. The base rib assembly of the vertical stabilizer is engaged with the clevis system. The plurality of lugs in the base rib assembly is secured to the plurality of clevises in the clevis system. Attachment of the vertical stabilizer to the aircraft fuselage, as well as subsequent inspection, may be performed from outside the aircraft.

Vertical short takeoff and landing (VSTOL) aircraft include primary airfoils extending outwardly from a forward region of the aircraft fuselage, and secondary empennage airfoils extending outwardly from an aft region of the aircraft fuselage so as to be separated from the forward primary airfoils and thereby define a space therebetween which accommodates non-cyclic controllable propellers operably driven by a respective engine of a propulsion unit. The propulsion units are mounted for pivotal movement within the defined space between the primary airfoil and the secondary empennage airfoils so as to achieve a first operational position wherein the thrust line of the propellers is orientated substantially parallel to the longitudinal axis of the fuselage and a second operational position wherein the thrust line of the propellers is oriented substantially perpendicular to the longitudinal axis of the aircraft. The propulsion units may be mounted aft of the aircraft center of gravity (CG).

Vertical short takeoff and landing (VSTOL) aircraft include primary airfoils extending outwardly from a forward region of the aircraft fuselage, and secondary empennage airfoils extending outwardly from an aft region of the aircraft fuselage so as to be separated from the forward primary airfoils and thereby define a space therebetween which accommodates non-cyclic controllable propellers operably driven by a respective engine of a propulsion unit. The propulsion units are mounted for pivotal movement within the defined space between the primary airfoil and the secondary empennage airfoils so as to achieve a first operational position wherein the thrust line of the propellers is orientated substantially parallel to the longitudinal axis of the fuselage and a second operational position wherein the thrust line of the propellers is oriented substantially perpendicular to the longitudinal axis of the aircraft. The propulsion units may be mounted aft of the aircraft center of gravity (CG).

An aircraft comprising a fixed structure, a fuselage mounted on the fixed structure and a tail unit system comprising a structural element housed inside the fuselage and mounted to be rotationally mobile relative to the fixed structure about a transverse axis of rotation parallel to a transverse axis of the aircraft. A first actuation system displaces the structural element in rotation about the transverse axis of rotation, on either side of the structural element. A horizontal tail unit has one end rotationally mobiley mounted on the structural element about a longitudinal axis of rotation parallel to a longitudinal axis of the aircraft and another end which extends out of the fuselage by passing through a window in the fuselage. For each horizontal tail unit, a second actuation system displaces the horizontal tail unit in rotation about the longitudinal axis of rotation.

An aircraft comprising a fixed structure, a fuselage mounted on the fixed structure and a tail unit system comprising a structural element housed inside the fuselage and mounted to be rotationally mobile relative to the fixed structure about a transverse axis of rotation parallel to a transverse axis of the aircraft. A first actuation system displaces the structural element in rotation about the transverse axis of rotation, on either side of the structural element. A horizontal tail unit has one end rotationally mobiley mounted on the structural element about a longitudinal axis of rotation parallel to a longitudinal axis of the aircraft and another end which extends out of the fuselage by passing through a window in the fuselage. For each horizontal tail unit, a second actuation system displaces the horizontal tail unit in rotation about the longitudinal axis of rotation.

A tiltrotor aircraft is designed to accommodate rotors of different diameters, as well as corresponding wings and fuselages with different span and length, while maintaining very high parts commonality, especially with respect to drive train and power source. This enables design and operation of a fleet of such aircraft with significantly different rotor diameters, which are nevertheless optimized for different missions. In preferred embodiments the rotors are configured to have high stiffness and low weight to reduce aero-structural dynamic issues across the fleet. Also in preferred embodiments drive systems are designed for a full range of speed, torque, and power associated with all intended rotors. Turboshaft engine speeds are restricted to a narrow RPM range, so that a single gearset can be replaced to achieve the desired rotor RPM. Also in preferred embodiments, aircraft in a fleet can differ in folded length, empty weight, payload length by up 50%.

An aeronautical composite structure configured to monitor a physical status of a bonded portion between structural components using a multi-core optical fiber. A method and system for monitoring the physical status of a bonded portion in an aeronautical composite structure also uses a multi-core optical fiber. More particularly, the invention relates to a structure and method for monitoring the physical status of a bonded portion of an aeronautical composite structure from its manufacturing to its use in flight using a multi-core optical fiber.

An aeronautical composite structure configured to monitor a physical status of a bonded portion between structural components using a multi-core optical fiber. A method and system for monitoring the physical status of a bonded portion in an aeronautical composite structure also uses a multi-core optical fiber. More particularly, the invention relates to a structure and method for monitoring the physical status of a bonded portion of an aeronautical composite structure from its manufacturing to its use in flight using a multi-core optical fiber.

A modular VTOL drone aircraft can include a primary processor, a plurality of propellers, one or more line replacement modules (“LRMs”) and one or more line replacement units (“LRUs”). LRMs can include a fuselage, a center wing, two booms, two outer wings, two vertical tails, a horizontal tail, and/or an engine. LRUs can include an avionics module, a radio communications assembly, a sensor package assembly, an ISR assembly, and/or a deployable payload assembly. Each LRM and LRU can be self-contained and removably attached to the remainder of the VTOL drone. Each LRM can be readily interchanged with another similar LRM, which can be of a different size. LRM interfaces can include a blind mate electric connector and/or a floating connector.

A modular VTOL drone aircraft can include a primary processor, a plurality of propellers, one or more line replacement modules (“LRMs”) and one or more line replacement units (“LRUs”). LRMs can include a fuselage, a center wing, two booms, two outer wings, two vertical tails, a horizontal tail, and/or an engine. LRUs can include an avionics module, a radio communications assembly, a sensor package assembly, an ISR assembly, and/or a deployable payload assembly. Each LRM and LRU can be self-contained and removably attached to the remainder of the VTOL drone. Each LRM can be readily interchanged with another similar LRM, which can be of a different size. LRM interfaces can include a blind mate electric connector and/or a floating connector.