Positional Error Analysis, A-10 Aircraft on Three-Axis Ground Mount

This report describes a test that was performed to determine the truth orientation of an A-10 aircraft mounted on a Scientific Atlanta Inc., Model PAEA-85 three-axis positioner at the Rome Air Development Center Newport Antenna Test Annex, and to estimate the errors inherent in using the aircraft positioning system in the process of antenna pattern testing. The report describes the following aspects of this effort: (1)Establishment of a reference coordinate system for the aircraft, and alignment of the aircraft on the positioner, (2) Description of the inclinometer system used for determining the aircraft orientation, (3) Test procedures, (4) Discussion of results, (5) Summary of errors, and (6) Conclusions and recommendations for the guidance of personnel using the system for aircraft antenna pattern testing. The total system error was determined to be less than 0.683 degrees for a pitch maneuver, and less than 0.533 degrees for a roll maneuver. (Author)