EFFECTS AT MACH NUMBERS OF 1.61 AND 2.01 OF CAMBER AND TWIST ON THE AERODYNAMIC CHARACTERISTICS OF THREE SWEPT WINGS HAFING THE SAME PLANFORM

An investigation has been made at Mach numbers of 1.61 and 2.01 to determine the aerodynamic characteristics of three wings having a sweepback of 50 degrees at the quarter-chord line, a taper ratio of 0.20, an NACA 65A005 thickness distribution, and an aspect ratio of 3.5. One wing was flat, one had at each spanwise station an a equals 0 mean line modified to have a maximum height of 4% chord, and one had a linear variation of twist with 6 degrees of washout at the tip. When compared with the flat wing, the effect of the linear variation of twist with 6 degrees of washout at the tip was to increase the lift-drag ratio when the leading edge was subsonic; but little increase in lift-drag ratio was obtained when the leading edge was supersonic. Pitching moment was increased and gave a positive trim point without greatly affecting the rate of change of pitching moment with lift coefficient. For the cambered wing the high minimum drag resulted in comparatively low liftdrag ratios. In addition, the pitching moments were decreased so that a negative trim point was obtained. (Author)