Abstract: The circuit of the present invention is able to detect and identify the position of several contactors.Each contactor (1) is mounted in series with a resistor (2). The first contacts (A.sub.N) are interconnected. The same applies for the second contacts (B.sub.N) and the third points (C.sub.N) of the branches established. In addition, the third points (C.sub.N) are separated by a second resistor (6). The measuring of the voltage between the first and third points (A, C) makes it possible to detect and identify the open and closed contactors and in addition is able to detect a malfunction.Application for detecting the position of the doors of a thrust reverser of a turbojet engine.

Abstract: A control system for hydraulically controlling variable engine structures is disclosed in which the control system utilizes hydraulic fluid identical to that used by the aircraft hydraulic control circuit. A high pressure hydraulic pump, driven by the aircraft engine, may be interconnected with the aircraft hydraulic control circuit, or may be associated with a separate fluid reservoir, to supply pressurized hydraulic fluid to the actuators for controlling the variable engine structures. The engine control circuit also includes a hydraulic pressure modulator to modulate the pressure of the fluid supplied to the actuator and a selector connected between the high pressure pump and, the modulator and the aircraft control circuit to selectively supply the high pressure hydraulic fluid from the pump to either the engine control circuit, or to the aircraft control circuit.