When was the autopilot invented?

Elmer Sperry had made his fortune with gyroscopic compasses for ships, and in 1912 his company adapted the idea to aircraft: a set of gyroscopes that detected deviations in pitch and roll and corrected them through servos driven by compressed air, connected to the controls. The device weighed about 18 kg (40 lb). His twenty-one-year-old son Lawrence took charge of testing and perfecting it. On 18 June 1914, at the Concours de la Sécurité en Aéroplane held along the Seine in Bezons, near Paris, Lawrence flew over the jury in a Curtiss C-2 flying boat with his hands raised while his mechanic, Emil Cachin, walked out onto the wing; the aircraft held level flight and corrected the imbalance on its own. He won first prize, worth 50,000 francs, and the "gyroscopic stabilizer" was recorded as the first working autopilot.

World War I and the 1920s expanded the use of gyroscopic instruments —artificial horizon, turn indicator, directional gyro— and on top of them Sperry Gyroscope built complete autopilots. In 1933 Wiley Post flew solo around the world in the Lockheed Vega Winnie Mae with an experimental Sperry unit that let him rest during long legs; in the second half of the 1930s three-axis models entered service on American bombers and transports, and during the war its ability to hold a steady course over the target was combined with the Norden bombsight. The next step was linking the autopilot to radio navigation aids: in September 1947 a US Air Force Douglas C-54 crossed the Atlantic from Newfoundland to England taking off, navigating and landing fully automatically, with the crew only observing.

In commercial aviation the milestone was landing with no visibility. Britain's BLEU (Blind Landing Experimental Unit) developed the autoland system first used with passengers by BEA's Hawker Siddeley Trident in 1965, and it received Category III certification in 1968. Concorde, the 747 and later generations added redundant autopilots capable of guiding the aircraft all the way to the runway. With the Airbus A320's fly-by-wire controls in 1988, the autopilot stopped being a bolt-on device and became just another function of the flight control computers, integrated with the flight management system that today can fly entire routes from shortly after takeoff.