GB1184349A - Improvements in Automatic Piloting Systems and relating to Transition Flight - Google Patents

Abstract

1,184,349. Automatic control of aircraft. SOC. DE FABRICATION D'INSTRUMENTS DE MESURE. March 9, 1967 [March 9, 1966], No. 11200/67. Heading G3R. R. Transition of an aircraft from normal flight to hovering is effected by switching an automatic pilot so that the aircraft is decelerated by a change of pitch altitude which is maintained constant with altitude until, at predetermined low speed, deceleration and altitude are reduced with speed until the hovering condition is achieved. In the arrangement described, pitch altitude of an aircraft is normally maintained constant by a pitch altitude detector associated with a servosystem automatically controlling pitch altitude. When switches are operated to initiate transition, a signal from a Doppler speed detector is progressively applied to the pitch servosystem through a limiter so that deceleration results and is maintained constant with the aid of an accelerometer. When the signal from the speed detector falls below a value determined by the limiter, pitch altitude, and hence deceleration, decreases with speed until a hovering condition is achieved. When transition is initiated, a signal from a radio altimeter is also applied without shock to a servosystem controlling altitude so that the latter is maintained constant when speed is above the limiting value, but is progressively reduced, when speed is below the limiting value, until the hovering condition is achieved.