Accession Number : ADA182197

Title :   Digital Control of Highly Augmented Combat Rotorcraft.

Descriptive Note : Technical memo.,

Corporate Author : NATIONAL AERONUATICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER

Personal Author(s) : Tischler,Mark B

PDF Url : ADA182197

Report Date : May 1987

Pagination or Media Count : 160

Abstract : Proposed concepts for the next generation of combat (scout/attack) helicopters are to be embodied in a complex, highly maneuverable, multiroled vehicle with avionics systems which are as important to mission success as the airframe itself. Single pilot and nap-of-the-Earth operations require handling qualities which minimize the involvement of the pilot in basic stabilization tasks. To meet these requirements will demand a full authority, high-gain, multimode, multiply-redundant, digital flight-control system. The gap between these requirements and current low-authority, low-bandwidth operational rotorcraft flight-control technology is considerable. this research aims at smoothing the transition between current technology and advanced concept requirements. The report: (a) extensively reviews the state of the art of high-bandwidth digital flight-control systems; (b) illustrates the important concepts in design and analysis of high-gain, digital systems with a detailed case study involving a current rotorcraft system. Frequency-domain methods for design and analysis are stressed in this report as essential for the practical implementation of high-gain control systems for rotorcraft. Approximate and exact methods are explained and illustrated for treating the important concerns which are unique to digital systems. Proposed specifications and flight-test data concerning the handling qualities of scout/attack rotorcraft imply restrictions on the maximum effective time delay which must be carefully considered in the design process.

Descriptors :   *HELICOPTERS, REQUIREMENTS, AVIONICS, CONTROL, DIGITAL SYSTEMS, AUGMENTATION, ROTARY WING AIRCRAFT, WARFARE, STABILIZATION, FLIGHT CONTROL SYSTEMS, FLIGHT TESTING, HANDLING, QUALITY, HIGH GAIN, TACTICAL AIRCRAFT, FLY BY WIRE CONTROL, ATTACK AIRCRAFT, LOW ALTITUDE, DELAY, TIME INTERVALS, PILOTS

Subject Categories : Helicopters

Distribution Statement : APPROVED FOR PUBLIC RELEASE