Gyroscope, JY ruh skohp, also called a gyro, is a device that uses rotation to produce a stable direction in space. A mechanical gyroscope, the oldest type of gyroscope, consists of a spinning wheel or ball, called the rotor, and a support system. Once the rotor is set in motion, the gyroscope resists any attempt to change its direction of rotation. Because of this property, gyroscopes are widely used in flight and navigation instruments. Several modern types of gyroscopes provide directional information without using a spinning rotor.
A gyroscopic instrument called the turn and slip indicator or turn-and-bank indicator helps pilots maintain the desired course of their aircraft in flight. Automatic flight control systems, also called automatic pilots, use gyros to steer a ship or plane closer to a course than a human pilot could. Gyroscopic devices also guide torpedoes, missiles, satellites, and space vehicles.
