Flush Airdata Sensing (FADS) System Calibration Procedures and Results for Blunt Forebodies. Meeting Paper AIAA-1999-4816, Research Engineering, NASA Dryden Flight Research Center

Cobleigh, Brent R. and Whitmore, Stephen A. and Haering Jr., Edward A. and Borrer, Jerry and Roback, V. Eric (1999) Flush Airdata Sensing (FADS) System Calibration Procedures and Results for Blunt Forebodies. Meeting Paper AIAA-1999-4816, Research Engineering, NASA Dryden Flight Research Center.

Full text available as: PDF - Requires Adobe Acrobat Reader or other PDF viewer.

Abstract

Blunt-forebody pressure data are used to study the behavior of the NASA Dryden Flight Research Center flush airdata sensing (FADS) pressure model and solution algorithm. The model relates surface pressure measurements to the airdata state. Spliced from the potential flow solution for uniform flow over a sphere and the modified Newtonian impact theory, the model is shown to apply to a wide range of blunt-forebody shapes and Mach numbers. Calibrations of a sphere, spherical cones, a Rankine half-body, and the F-14, F/A-18, X-33, X-34, and X-38 configurations are shown. The three calibration parameters are well-behaved from Mach 0.25 to Mach 5.0, an angle-of-attack range extending to greater than 30 degrees, and an angle-of-sideslip range extending to greater than 15 degrees. Contrary to the sharp calibration changes found on traditional pitot-static systems at transonic speeds, the FADS calibrations are smooth, monotonic functions of Mach number and effective angles of attack and sideslip. Because the FADS calibration is sensitive to pressure port location, detailed measurements of the actual pressure port locations on the flight vehicle are required and the wind-tunnel calibration model should have pressure ports in similar locations. The procedure for calibrating a FADS system is outlined.

EPrint Type:	Other
Keywords:	Blunt forebody, Calibration, F-14 aircraft, Flush airdata, FADS, F/A-18 aircraft, X-33 vehicle, X-34 vehicle, X-38 vehicle
Subjects:	Aircraft/Project: X-34 (01 - 09) Aeronautics: (06) Avionics And Aircraft Instrumentation Aircraft/Project: F-18 Aircraft/Project: X-38 Aircraft/Project: F-14 Aircraft/Project: X-33
ID Code:	1273
Deposited On:	06 Febuary 2007
Additional Information:	28 pages. American Institute of Aeronautics and Astronautics 9th International Space Planes and Hypersonic Systems and Technologies Conference, Norfolk, Virginia, November 1-5, 1999.