Free-flight measurements of the drag and longitudinal stability of a transonic M-wing aircraft

Free-flight tests have been made on a model of an M-wing aircraft designed to cruise at M = 1·2 with a subsonic type of flow on the wing surfaces. Results are presented for the zero-lift drag and longitudinal stability characteristics over the Mach number range from 0·9 to 1·3. It is shown that the design aims have been achieved in that no evidence of shocks in the wing root was found and that some suppression of the wing wave drag occurred. The results are compared with those from free-flight tests on a sweptwing model having the same body, fin and tailplane configuration.