NACA-RM-A50K28 REV A

Abstract

INTRODUCTION <br>It has boon noted in previous investigations (e.g., reference 1) that swept-back wings without twist or camber and having small leading-edge radii undergo serious changes in aerodynamic characteristics at relatively low lift coefficients. It is believed that these deficiencies may be the result of leading-edge separation associated with the use of sections having small leading-edge radii such as thin NACA 6-series sections. <br>Preliminary tests conducted at low speed have indicated that modifying a swept-back wing with this type of section by increasing the leading-edge radius and introducing a small amount of camber over the attack. The present investigation, conducted in the Ames 12-foot pressure wind tunnel, was undertaken to extend the study of the effects of such modifications over a wide range of Reynolds numbers and to high subsonic Mach numbers. <br>The model wing, which was modified for this investigation, had 35 of sweepback and employed the NACA 64A010 section normal to the quarter-chord line. The modification entailed an increase in the leading-edge radius and the addition of a small amount of camber over the forward portion of the chord. As a basis for judging the effectiveness of the modification, data from reference 1 on the unmodified wing have been included herein. The data for both wings have been reduced to coefficient form on the basis of their respective wing areas.