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The Boeing X-50A Dragonfly, formerly known as the Canard Rotor/Wing Demonstrator, was a VTOL rotor wing experimental unmanned aerial vehicle that was developed by Boeing and DARPA to demonstrate the principle that a helicopter's rotor could be stopped in flight and act as a fixed wing, enabling it to transition between fixed-wing and rotary-wing flight.
A tiltrotor is an aircraft that generates lift and propulsion by way of one or more powered rotors (sometimes called proprotors) mounted on rotating shafts or nacelles usually at the ends of a fixed wing. Almost all tiltrotors use a transverse rotor design, with a few exceptions that use other multirotor layouts.
The stopped rotor type has a separate system for forward thrust. It takes off like a helicopter but for forward flight the rotor stops and acts as a fixed wing. The gyrocopter is similar except that the rotor continues to spin and to generate a significant amount of lift, and so is classed as a rotorcraft and not a convertiplane.
A rotor wing aircraft has been attempted but is not in wide use. The Boeing X-50 Dragonfly had a two-bladed rotor driven by the engine for takeoff. In horizontal flight the rotor stopped to act like a wing. Fixed canard and tail surfaces provided lift during transition, and also stability and control in forward flight. Both examples of this ...
The tail rotor system rotates airfoils, small wings called blades, that vary in pitch in order to vary the amount of thrust they produce.The blades most often utilize a composite material construction, such as a core made of aluminum honeycomb or plasticized paper honeycomb, covered in a skin made of aluminum or carbon fiber composite.
The XV-3 returned to the Ames wind tunnel in October 1958 to collect more data before it could be flown again. As a result of the wind tunnel testing, the rotor diameter was reduced, wing structure was increased and strengthened, and the rotor controls were stiffened. The XV-3 resumed flight testing at Bell's facility on 12 December 1958.
A fixed-wing aircraft is a heavier-than-air aircraft, such as an airplane, which is capable of flight using aerodynamic lift. Fixed-wing aircraft are distinct from rotary-wing aircraft (in which a rotor mounted on a spinning shaft generates lift), and ornithopters (in which the wings oscillate to generate lift).
This energy transfer from the rotor to the air is the induced power loss of the rotary wing, which is analogous to the lift-induced drag of a fixed-wing aircraft. Conservation of linear momentum relates the induced velocity downstream in the far wake field to the rotor thrust per unit of mass flow .