Accession Number : ADA188964

Title :   The Impact of Vertical Axis Characteristics on Helicopter Handling Qualities,

Corporate Author : NATIONAL AERONAUTICAL ESTABLISHMENT OTTAWA (ONTARIO) FLIGHT RESEARCH LAB

Personal Author(s) : Baillie, S W ; Morgan, J M

PDF Url : ADA188964

Report Date : Aug 1987

Pagination or Media Count : 70

Abstract : The results of two in-flight simulation programs on the impact of vertical axis characteristics on rotorcraft handling qualities are presented. The parameters investigated were heave damping, thrust to weight ratio, and various dynamic response characteristics of the combined engine, governor and rotor system. Flight tasks included hover, hover manoeuvring and nap of the earth flight. Evaluation of 11 configurations where heave damping and thrust to weight ratio values were varied provides the basis to suggest that the amount of heave damping represented by Zw = -0.20/sec and a thrust to weight ratio of 1.08 are boundary values for Level 1 helicopter handling qualities. These results are compared with other relevant work. Stabilization and control of engine torque was found to be a major source of pilot workload for models with higher order engine-rotor system response characteristics of a 3 db resonant peak in the transfer function between collective and engine torque which is postulated as an upper limit for Level 1 handling qualities. The benefit of displacing this peak to higher frequencies, corresponding to separating the resonance from the typical pilot's bandwidth, is suggested.

Descriptors :   *FLIGHT SIMULATION, *HELICOPTERS, BANDWIDTH, CANADA, CONTROL, DAMPING, DYNAMIC RESPONSE, FLIGHT, FREQUENCY, HANDLING, HEAVING, HOVERING, INFLIGHT, LIMITATIONS, PEAK VALUES, PILOTS, QUALITY, RATIOS, ROTARY WING AIRCRAFT, ROTORS, SOURCES, THRUST, TORQUE, TRANSFER FUNCTIONS, VERTICAL ORIENTATION, WEIGHT, WORKLOAD, MAN MACHINE SYSTEMS, FLIGHT CONTROL SYSTEMS, COMPUTER PROGRAMS, TURNING FLIGHT, PITCH(MOTION), GROUND ROLL(AERONAUTICS), HELICOPTER ENGINES, FLIGHT MANEUVERS

Subject Categories : Aerodynamics
      Human Factors Engineering & Man Machine System

Distribution Statement : APPROVED FOR PUBLIC RELEASE