during take-off and landing. Autopilots are complex on-board mechanisms that detect deviations from an aircraft route and make appropriate adjustments to the flight controls.Flight decks are also equipped with radar that warn pilots of approaching hazards, such as mountain ranges, bad weather, and other aircraft. Supersonic jetliners fly faster than the speed of sound. There are many supersonic military aircraft, but only two supersonic passenger-carrying aircraft(also called SSTs,or supersonic transports)