An aircraft includes an airframe with an upper portion and an extending tail, a counter-rotating, coaxial main rotor assembly disposed at the upper portion of the airframe, a translational thrust system, including a propeller, disposed at the extending tail of the airframe and a flight control system configured to control at least one of revolutions-per-minute (RPM) and pitch of the propeller of the translational thrust system in response to an input speed or acceleration command.

A method and apparatus for determining a discrete position of a first surface of an aircraft is disclosed. The first surface and a second surface movable relative to the first surface are provided. A sensor is disposed on one of the first surface and a second surface and a magnetic field source disposed on the other of the first surface and the second surface. The sensor detects a local magnetic field related to the magnetic field source and generates a voltage indicative of strength of the local magnetic field. The strength of the local magnetic field and therefore the generated voltage is related to a relative position between the sensor and the magnetic field source. The relative distance between the first surface and the second surface is determined from the generated voltage.

The rotor of a hybrid aerodyne for producing lift by rotating during a stage of vertical flight and then for being held stationary and stored longitudinally during a stage of cruising flight has at least one single-blade with a counterweight. The length of the active blade that generates lift of the rotor while rotating is significantly shorter than the length of the radius of the rotor. The portion that carries the active blade that makes the connection between the active blade and rotor mast is structurally rigid. The rigid portion that carries the active blade presents a cross-section optimized to provide zero or almost zero lift and very little aerodynamic drag while the rotor is rotating. The assembly is hinged about a transverse axis perpendicular to the vertical axis of the rotor and substantially on the vertical axis of the rotor mast.

A flight control system for a rotary-wing aircraft includes a shape sensor and a controller. The shape sensor is configured to measure a shape of a rotor blade during movement of the rotor blade. The controller is communicably coupled to the shape sensor and is configured to (i) receive, from the shape sensor, a first signal indicative of a first blade shape; (ii) receive a blade characteristic regarding the rotor blade; and (iii) determine at least one of a moment or force associated with the rotor blade based on the first signal and the blade characteristic.

A system for reconstructing sensor data in a rotor system that comprises a rotating component of the rotor system, a plurality of sensors in the rotating component to sense at least one of loads and motion characteristics in the rotating component and to generate sensor data, and an analysis unit to generate reconstructed sensor data from the sensor data using numerical analysis for low-rank matrices.

According to one embodiment, a flapping measurement system may include a position sensor and a controller. The position sensor may be disposed on the flapping plane of a rotor blade and operable to provide position measurements identifying locations of the position sensor during operation of the rotor blade. The controller may be operable to identify flapping of the rotor blade based on the position measurements.

The present invention includes an apparatus and method for automatically adjusting the tracking of one or more blades comprising: a blade tracking adjustment mechanism connected to one or more blades of an aircraft; a blade tracking measurement system that measures the tracking of the one or more blades; and a computer that receives an output from the blade tracking measurement system with tracking information for each of the one or more blades; wherein the computer outputs instructions for the blade tracking adjustment mechanism to change a pitch of one or more of the blades to correct blade tracking.

A balancing apparatus for a rotary element is provided and includes a central hub portion and radial elements extending outwardly from the central hub portion. The balancing apparatus includes a conduit extending along the radial elements via the central hub portion, a mass movable within the conduit between the radial elements via the central hub portion and a mass balancing system which directs a movement of the mass within the conduit into and out of the central hub portion and along the radial elements.

A control system is provided and includes a servo control system configured to control aerodynamic element pitching, an optical sensor system disposed along rotor blades to generate an optical response reflective of rotor feedback states of the rotor blades and a processing unit operably coupled between the servo control and optical sensor systems, the processing unit being configured to calculate strain in the rotor blades from the optical response, convert the calculated strain into readings of the rotor feedback states and issue a servo command to the servo control system as an instruction for controlling the aerodynamic element pitching.

A system for manufacturing a particulate-binder composite article including a mold defining a mold cavity, a first opening into the mold cavity, and a second opening into the mold cavity, a mass of a particulate material received in the mold cavity, a binder source in selective fluid communication with the mold cavity by way of the first opening, the binder source including a binder material, a first filter disposed across the first opening, the first filter being permeable to the binder material and substantially impermeable to the particulate material, and a second filter disposed across the second opening, the second filter being permeable to air and substantially impermeable to the particulate material.