Abstract: A method and system to control a rotor system includes automatically changing a rotor speed of the rotor system of the tiltrotor aircraft while moving the rotor system from a first position and a first rotor speed to a second position and a second rotor speed over a time period in accordance with an acceleration-rate profile that varies over the time period using a controller communicably coupled to the rotor system of the tiltrotor aircraft.

Abstract: A method and system to control a rotor system includes providing a controller communicably coupled to the rotor system, and automatically changing a rotor speed of the rotor system from a first rotor speed in a first flight mode to a second rotor speed in a second flight mode over a time period using the controller in accordance with an acceleration-rate profile that varies over the time period.

Abstract: A flapping control system for a proprotor assembly of a tiltrotor aircraft includes one or more sensors operable to detect one or more flight parameters of the tiltrotor aircraft to form sensor data. The sensors include a proprotor flapping sensor to detect a proprotor flapping measurement. The flapping control system includes a flapping control module in data communication with the sensors. The flapping control module includes a maneuver detection module to detect whether the tiltrotor aircraft is in a maneuver mode using the sensor data. The flapping control module identifies a maneuver flapping threshold associated with the maneuver mode. The flapping control module generates a swashplate command using the proprotor flapping measurement and the maneuver flapping threshold, and sends the swashplate command to the proprotor assembly to reduce flapping of the proprotor assembly.

Abstract: A roll control system controls roll control surfaces of an aircraft that are capable of causing the aircraft to perform a roll maneuver by respectively deflecting in upward and downward directions. The roll control system includes deflection limiter units for respectively limiting angles of deflection of the roll control surfaces, and further includes deflection rate limiter units for respectively limiting rates of deflection of the roll control surfaces. The deflection limiter unit limits the roll control surfaces to deflection distances and deflection rates based at least in part on the deflection direction of the roll control surfaces. For a given set of flight conditions, such as airspeed, if a roll control surface is deflecting upwardly, it is less limited by the roll control system in terms of deflection distance and deflection rate than if the roll control surface is deflecting downwardly.

Abstract: A method and system to control a rotor system includes providing a controller communicably coupled to the rotor system, and automatically changing a rotor speed of the rotor system from a first rotor speed in a first flight mode to a second rotor speed in a second flight mode over a time period using the controller in accordance with an acceleration-rate profile that varies over the time period.

Abstract: A tiltrotor aircraft is operable in a helicopter flight mode and an airplane flight mode. The tiltrotor aircraft has an airframe including a fuselage and a wing. First and second pylon assemblies are respectively coupled to the airframe proximate outboard ends of the wing. Each pylon assembly includes a mast and a proprotor assembly operable to rotate with the mast to generate thrust. The pylon assemblies are rotatable relative to the wing to selectively operate the tiltrotor aircraft between the helicopter flight mode and the airplane flight mode. The thrust of each proprotor assembly has a thrust vector with an inboard angle between about 5 degrees and about 12 degrees relative to an axis parallel to the yaw axis during hover operations, thereby reducing download on the airframe and improving hover efficiency.

Abstract: A flapping control system for a proprotor assembly of a tiltrotor aircraft includes one or more sensors operable to detect one or more flight parameters of the tiltrotor aircraft to form sensor data. The sensors include a proprotor flapping sensor to detect a proprotor flapping measurement. The flapping control system includes a flapping control module in data communication with the sensors. The flapping control module includes a maneuver detection module to detect whether the tiltrotor aircraft is in a maneuver mode using the sensor data. The flapping control module identifies a maneuver flapping threshold associated with the maneuver mode. The flapping control module generates a swashplate command using the proprotor flapping measurement and the maneuver flapping threshold, and sends the swashplate command to the proprotor assembly to reduce flapping of the proprotor assembly.

Abstract: A roll control system controls roll control surfaces of an aircraft that are capable of causing the aircraft to perform a roll maneuver by respectively deflecting in upward and downward directions. The roll control system includes deflection limiter units for respectively limiting angles of deflection of the roll control surfaces, and further includes deflection rate limiter units for respectively limiting rates of deflection of the roll control surfaces. The deflection limiter unit limits the roll control surfaces to deflection distances and deflection rates based at least in part on the deflection direction of the roll control surfaces. For a given set of flight conditions, such as airspeed, if a roll control surface is deflecting upwardly, it is less limited by the roll control system in terms of deflection distance and deflection rate than if the roll control surface is deflecting downwardly.

Abstract: The present invention includes an adjustable Pitot tube and method for using the same for operating or flight testing an aircraft comprising: a Pitot probe; a streamline tube connected to the Pitot probe; a mount on the aircraft connected to the streamline tube, wherein the streamline tube can at least one of rotate about an axis of the mount, or the streamline tube can move the Pitot probe closer to, or away from, a skin of the aircraft.

Abstract: The present invention includes an adjustable Pitot tube and method for using the same for operating or flight testing an aircraft comprising: a Pitot probe; a streamline tube connected to the Pitot probe; a mount on the aircraft connected to the streamline tube, wherein the streamline tube can at least one of rotate about an axis of the mount, or the streamline tube can move the Pitot probe closer to, or away from, a skin of the aircraft.