USE OF SATELLITE NAVIGATION FOR SAILPLANE PERFORMANCE MEASUREMENTS

Abstract

Currently the most commonly used method for sailplane performance measurements is comparison to a sailplane with well known performance, as performed routinely at the Idaflieg summer meetings. Necessary for evaluation of the data is a very precise knowledge of the relative position of the sailplanes during the test flight. Carrier-phase positioning with satellite navigation systems is able to provide this precise reference, not only at the beginning and end of each measurement interval, but during the entire flight. Additional sensors are employed to reduce the influence of the pilot' s flying technique. The basics of sailplane performance calibration are discussed, as is the principle of carrier-phase positioning and its implementation for the taskat hand. A small and simple measurement system concept is described and flight tested. Experiences using this technique in parallel to the classical measurements during the Idaflieg summer meetings of 1995 and'1996 are discussed and the potential and restrictions of the new technique is evaluated. Results available at the current time show the new technique to be comparable to current methods in accurary, but with the potential to reduce necessaryman power, time and cost in performing and evaluating sailplane performance measurements.