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A Bell 47 helicopter, an early example of a powered rotorcraft. A rotary-wing aircraft, rotorwing aircraft or rotorcraft is a heavier-than-air aircraft with rotary wings that spin around a vertical mast to generate lift. The assembly of several rotor blades mounted on a single mast is referred to as a rotor.
Abrasion strips on helicopter rotor blades are made of metal, often titanium or nickel, which are very hard, but less hard than sand. When a helicopter flies low to the ground in desert environments, sand striking the rotor blade can cause erosion. At night, sand hitting the metal abrasion strip causes a visible corona or halo around the rotor ...
Rotorcraft, or rotary-wing aircraft, use a spinning rotor with aerofoil cross-section blades (a rotary wing) to provide lift. Types include helicopters, autogyros, and various hybrids such as gyrodynes and compound rotorcraft. Helicopters have a rotor turned by an engine-driven shaft. The rotor pushes air downward to create lift.
Like helicopters, these aircraft do not need a long runway to take off and land, but they have a speed and performance similar to standard fixed-wing aircraft in combat or other situations. Some powered-lift aircraft, like the Bell Boeing V-22 Osprey used by the United States Marines, use a tiltrotor or tiltwing. These are called a convertiplane.
The Bell 407 is a four-blade, single-engine, civil utility helicopter. A derivative of the Bell 206L-4 LongRanger, the 407 uses the four-blade, soft-in-plane design rotor with composite hub developed for the United States Army's OH-58D Kiowa Warrior instead of the two-blade, semi-rigid, teetering rotor of the 206L-4.
Any rotor system has a delay between the point in rotation where the controls introduce a change in pitch and the point where the desired change in the rotor blade's flight occurs. This difference is caused by phase lag, often confused with gyroscopic precession. A rotor is an oscillatory system that obeys the laws that govern vibration—which ...
The Bell V-280 Valor is a tiltrotor aircraft being developed by Bell Helicopter for the United States Army's Future Vertical Lift (FVL) program. [2] The aircraft was officially unveiled at the 2013 Army Aviation Association of America's (AAAA) Annual Professional Forum and Exposition in Fort Worth, Texas.
A coaxial-rotor aircraft is an aircraft whose rotors are mounted one above the other on concentric shafts, with the same axis of rotation, but turning in opposite directions (contra-rotating). This rotor configuration is a feature of helicopters produced by the Russian Kamov helicopter design bureau .