A new flight reference display for powered-lift STOL aircraft was proposed and evaluated in actual flight environment. The display was developed to provide a simple monitoring system of STOL safety margins with good handling characteristics in place of a speed indicator. Using this display, pilots repeated simulated approaches of the experimental jet STOL “ASKA” using the VSRA as an in-flight simulator. In the evaluation, emphasis was placed on agreement between the display and the motion cues experienced by the pilot. Pilot comments and flight data confirmed satisfactory control characteristics and safety margin presentation of the display.