Throttle control system having real time computed thrust vs. throttle position function

摘要

A throttle controller includes a manual mode where engine output is a function of throttle lever angle, and an alternatively selectable Speed Hold/Thrust Hold mode which is initiated when the throttle is placed in a center Hold position. Throttle operation during the Speed Hold mode is governed by (i) a selected speed entered at a mode control panel, or (ii) a speed existing when the lever was placed in the Hold detent, given that no speed is entered and selected at that mode control panel or (iii) a selected speed/thrust designated in a flight plan entered into the aircraft's flight management computer. During the Thrust Hold mode, the throttle controller maintains the level of thrust which existed when the throttle lever was placed in the Hold detent. When out of the Hold detent, the controller operates to control output thrust as a function of Throttle Lever Angle (TLA). Failure of the Speed Hold mode or Flight Plan mode, causes autothrottle operation to default through a priority scheme, which generally results in a mode where the airspeed existing at the time of failure is maintained. In order to allow the pilot to make very small changes in engine thrust without increasing the total range of throttle movement, every time the throttle is placed in the center Hold position a new thrust versus throttle lever angle function is calculated to afford increased throttle movement sensitivity. IMAGE