Accession Number : AD0652931

Title :   INVESTIGATION ON THE IMPROVEMENT OF LONGITUDINAL STABILITY OF A JET AIRCRAFT BY THE USE OF A PITCH-DAMPER,

Corporate Author : ADVISORY GROUP FOR AERONAUTICAL RESEARCH AND DEVELOPMENT PARIS (FRANCE)

Personal Author(s) : Mautino,R.

Report Date : APR 1961

Pagination or Media Count : 53

Abstract : In view of the possibility of a future installation of a pitch-damper on the (FIAT) G 91 aircraft, a preliminary study with the aid of an analogue computer was carried out on the aeroplane flying qualities for different flight conditions (weight, centre of gravity, altitude, speed) with and without pitch-damper, and also with a failing pitch-damper, in order to evaluate the efficiency and stability of a system of this kind and the influence of the various parameters. Each configuration was repeated for various pitch-damper gain values to determine an optimum value, acceptable for use throughout the aeroplane operational envelope. With the optimum gain value defined, a flight test schedule was then developed, on the basis of the examination of these results, with the pitch-damper on and off, at different altitudes and Mach numbers, with various gain values and with a disturbance of varying level excited by the pilot deflecting and counter-maneuvering the elevator. The results achieved, both in the approximation of the transfer functions and in the simulation of the transients, proved satisfactory and quite suitable for preliminary theoretical evaluation of the efficiency and stability of a servo system involving such complexities. (Author)

Descriptors :   (*JET FIGHTERS, STABILIZATION SYSTEMS), (*PITCH(MOTION), DAMPING), STABILITY, ITALY, EFFICIENCY, OPTIMIZATION, FLIGHT TESTING

Subject Categories : Attack and Fighter Aircraft
      Flight Control and Instrumentation

Distribution Statement : APPROVED FOR PUBLIC RELEASE