Accession Number : ADB120425

Title :   F-111C Excessive Elevator Position Indications,

Corporate Author : AIRCRAFT RESEARCH AND DEVELOPMENT UNIT EDINBURGH (AUSTRALIA)

Personal Author(s) : Poynton, Sqnldr T.

Report Date : NOV 1987

Pagination or Media Count : 54

Abstract : Flight-test of the F-111C aircraft with the Pavetack/Guided Weapons pod fitted revealed that the maximum elevator position indications for forward CG limitations were being exceeded. Operational crews reported that, although discovered with the PT/GW system fitted, the problem was common for all F-111C operations. The elevator position indication values being reported indicated that the F-111C aircraft were possibly being operated with centres of gravity beyond the forward limit. Technical Investigation No 940 tasked Aircraft Research and Development Unit to conduct flight tests to verify both the forward and aft CG limits and to provide elevator position indication check values for aircrew use during the final approach landing phase. Four aircraft configurations were tested in the landing configuration. These were: (1) flaps 34 degrees with slats and gear extended; (2) flaps 25 degrees with slats and gear extended; (3) slats and gear extended without flaps; and (4) gear extended without flaps or slats. The CG limits and associated elevator position indication check values for the test landing configurations were determined using a combination of both quantitative and qualitative data analysis. Wing sweep for landing and CG envelope graphical information were computed from the flight-test results.

Descriptors :   *AIRCRAFT LANDINGS, *JET FIGHTERS, CONFIGURATIONS, DATA PROCESSING, ELEVATORS, FLIGHT ENVELOPE, EXTERNAL STORES, FLAPS(CONTROL SURFACES), FLIGHT CREWS, FLIGHT TESTING, FORWARD AREAS, GRAPHICS, GRAVITY, GUIDED WEAPONS, LIMITATIONS, POSITION(LOCATION), RESEARCH MANAGEMENT, INDICATORS, FLIGHT CONTROL SYSTEMS, HANDLING, SWEPT WINGS, APPROACH, CENTER OF GRAVITY, LANDING GEAR, LOAD DISTRIBUTION, JET ENGINE FUELS, AUSTRALIA.

Subject Categories : Military Aircraft Operations
      Attack and Fighter Aircraft
      Flight Control and Instrumentation

Distribution Statement : APPROVED FOR PUBLIC RELEASE