Abstract: A throttle controller for a vehicle, such as an aircraft, having a plurality of engines (36-42). Each engine is regulated by a throttle. The controller includes a thrust sensor (44), a speed sensor (IAS), and an actuator (10). The thrust sensor (44) responds to the engines (36-42) to produce a plurality of thrust signals (22). These thrust signals correspond to the thrust produced by a different corresponding one of the engines. The speed sensor (IAS) can produce a speed signal corresponding to aircraft speed. The actuator (10) can adjust the throttle of each engine. The actuator is connected to the speed (IAS) and thrust sensors (44) and can respond to their signals to adjust each throttle and balance the thrust of the engines.

Abstract: A controller (FIGS. 1, 2) is provided in a dual servo system that drives a controlled element (22) with mechanically coupled first and second servos (24 and 44). This controller has a first (10, 110, 112) and second (14, 108, 114) digital process subsystem. The first digital processing subsystem can simultaneously drive the first and second servos. This first processing subsystem is operable to measure the responsiveness of the servos to the first processing subsystem and provide a self-checking indication. The second digital processing subsystem measures the responsiveness of these servos to the first digital processing subsystem and can provide an independent indication of failure. The foregoing can be extended to multiple channels for controlling independent multiple elements such as aircraft control surfaces. Preferably, two different types of computers (10, 14; 108, 110, 112, 114) with different programs can be employed to control three control channels.

Abstract: A flap compensation system is provided which reduces the pilot applied force required to hold the pitch attitude of an aircraft within specified limits upon pilot operation of the aircraft flaps by automatically displacing the horizontal stabilizer of the craft as a function of flap displacement.