NASA-TN-D-6432
- Version
- 151 Downloads
- 1.72 MB File Size
- 1 File Count
- June 16, 2016 Create Date
- June 16, 2016 Last Updated
Motion Cue and Simulation Fidelity Aspects of the Validation of a General Purpose Airborne Simulator
The NASA general purpose airborne simulator (GPAS), a modified Lockheed
JetStar airplane, was validated by comparing pilot comments, ratings, and flight time
histories obtained from the XB-70 airplane and the GPAS simulating the XB-70 airplane.
Reference 1, which treated the handling—qualities results of the validation program,
showed the GPAS to be capable of accurate and realistic simulation of the XB—70 air—
plane at two cruise flight conditions, Mach 1. 2 at 12,192 meters (40, 000 feet) altitude
and Mach 2. 35 at 16, 764 meters (55, 000 feet) altitude.
Motion and visual cue influences are critical in any simulator validation, especially
in the analysis of pilot-noted discrepancies in the flying qualities of the simulator com—
pared with the actual aircraft. Two major causes of such discrepancies are inaccura—
cies in the aerodynamic data and distortion due to the motion system. In the GPAS
validation program (ref, 1), experiments were conducted to determine the sensitivity
of the pilot to certain motion cues which were not being duplicated exactly, in order to
assess the influence of these mismatched cues. The results of the experiments are
presented in this report. '
The selection of a simulator configuration and the operational experience with the
model-following type of simulation are also pertinent to the validation results. The
dynamic characteristics of the combined analog model/JetStar system are determined
by the particular combination of feedback loops and control gains used. The methods
used to configure the simulator and measure the resultant dynamics are discussed
herein.
The advantages of the model-controlled system over the more conventional response
feedback system, which utilizes feedback loops to augment base aircraft stability deriva-
tives, are primarily greatly reduced in—flight calibration time and relative insensitivity
to variations in base aircraft weight, inertia, and aerodynamic characteristics. The
model—following system is covered later in more detail.
File | Action |
---|---|
NASA-TN-D-6432 Motion Cue and Simulation Fidelity Aspects of the Validation of a General Purpose Airborne Simulator.pdf | Download |
Comment On This Post