Accession Number : ADD014051

Title :   Back-Up Control System for F101 Engine and Its Derivatives.

Descriptive Note : Patent, Filed 14 May 87, patented 3 Jan 89,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Hutto, Walter D , Jr ; Stockton, William W

Report Date : 03 Jan 1989

Pagination or Media Count : 13

Abstract : A back-up control system is implemented in a single engine aircraft to provide inactivation of a faulty primary system and engagement of secondary system, and thereby provide a means of maintaining controllable flight sustaining thrust. The aircraft's hydromechanical main engine control and its companion pressure and temperature sensors can develop faults which can result in the inability of the engine to deliver flight sustaining thrust. The electronic control contains logic functions which indicate failure of the main engine control when all of the following exists for a minimum of three seconds: a) the power lever is at a position requesting a level of dry thrust which exceeds a predetermined threshold; b) core engine speed is below that required to deliver the predetermined level of dry thrust; c) core engine speed is not increasing; and d) turbine temperature is beneath the maximum allowable limit. The backup system is used in conjunction with a three position cockpit switch having 'normal', 'on' and 'standby' position. In the 'normal' position the back-up system is off and must be manually activated by switching to the 'on' position. In the 'standby' position, the backup system is automatically activated when the necessary conditions occur. Patents. (EDC)

Descriptors :   *THRUST CONTROL, *BACKUP SYSTEMS, *CONTROL SYSTEMS, *PATENTS, ACTIVATION, AIRCRAFT, COCKPITS, CONTROL, CORES, DETECTORS, ELECTRONIC EQUIPMENT, TURBOFAN ENGINES, LOGIC CIRCUITS, MANUAL OPERATION, POSITION(LOCATION), RATES, SWITCHES, SWITCHING, TEMPERATURE, TEMPERATURE SENSITIVE ELEMENTS, AXIAL FLOW TURBINES

Subject Categories : Flight Control and Instrumentation
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE