NACA-RM-L53J21

Abstract

INTRODUCTION <br>The spoiler used as a lateral-control device has been the subject of considerable investigation at low and high speeds, and on both swept and unswept wings (refs. 1 to 3). Recent investigations of spoilers used as lateral-control devices have shown that on thin wings with small leading-edge radii the unvented spoiler loses effectiveness rapidly as the angle of attack is increased above 8&#176; (refs. 2 and 3). However, investigations at low and high subsonic speeds as reported in references 3 to 5 have shown that this loss in effectiveness at the higher angles of attack could be substantially reduced by using a slot in the wing behind the spoiler that would allow the air to flow through the wing from the lower to the upper surface when the spoiler was deflected. <br>The purpose of this investigation was to extend through the transonic speed range previous low and high subsonic speed investigations of spoiler-slut-deflector devices for lateral control. The investigation was made in the Langley high-speed 7- by 10-foot tunnel using the transonic bump to obtain Mach numbers from 0.62 to 1.20. The angle-of-attack range was -4&#176; to 24&#176;. Rolling, yawing, and pitching moments, and lift and drag were obtained with spoiler alone, spoiler-gap lip combination, and spoiler-slot deflector combination.