A very accurate measurement system and a data reduction method have been developed to extract performance data from a single dynamic maneuver, in order to reduce the large amoimt of flight hours required for the determination of these data by means of measurements in steady flight. In order to evaluate the applicability of this method to a modem jet transport aircraft, a test program has been carried out with the prototype of the Fokker F28 Fellowship. Preliminary results, based on lift-drag polars, show an excellent agreement between the new developed method and "traditional" measurements in steady flight.