Transition Detection on Supersonic Natural Laminar Flow Wing in the Flight

The experimental validation of natural laminar flow wing designed with the original CFDbased inverse design method is carried out by the flight test of an unmanned and scaled supersonic experimental airplane. It is the first challenge to apply the natural laminar flow wing concept to a supersonic vehicle. The concept of natural laminar flow wing is validated by measuring the surface pressure and the transition location. In this paper, the transition characteristics detected by the hot-film sensors and dynamic pressure transducers are discussed. Transition location is classified by using newly introduced quantity, called “transition level”, based on objective criteria. The transition location detected experimentally is in good agreement with numerically predicted location, and the natural laminar flow effect is confirmed at the design condition.