Radio Controlled R/C helicopter flying in the park.
Radio Controlled (RC) helicopters are model aircraft which are distinct from RC airplanes because of the differences in construction, aerodynamics, and flight training. Several basic designs of RC helicopters exist, some more maneuverable than others. The more maneuverable designs are often harder to fly, but benefit from greater aerobatic capabilities. Flight controls allow pilots to control the collective and throttle (usually linked together), the cyclic controls (pitch and roll), and the tail rotor (yaw). Controlling these in unison enables the helicopter to perform most of the maneuvers an aeroplane can do, and many that aeroplanes cannot, such as hovering and backwards flight; in this manner, they are quite similar in operation to full-sized helicopters.. The engines used are typically methanol-powered two-stroke motors, but electric brushless motors combined with a high-performance lithium polymer battery are also used. RC helicopters can range in price from as little as $30 to several thousands of dollars.