NACA-RM-A55D11

Abstract

INTRODUCTION <br>The adverse effects of wing-tip stall on the low-speed stability and drag characteristics of swept-wing airplanes are widely recognized. To delay wing-tip stall to higher lift coefficients, the use of large increases in leading-edge radius together with slight amounts of forward camber has been shown to be effective on wings of moderate thickness (refs. 1 to 3). However, there appear to be Tuttle data on the high speed effects of such modifications on wing-body combinations, and not any data at all on their effects on thin wings. <br>The purpose of the investigation reported herein was to evaluate the effects of such a modification cm a thin swept wing of low aspect ratio k combination with a body at both subsonic and supersonic speeds. The modified airfoil section was designed to attain a given low-speed ^clmax, comparable to that which might be expected from leading-edge flaps. The experimental three-dimensional results, obtained at several Reynolds numbers, are presented and discussed from both the low-speed and high-speed standpoints. The measured low-speed characteristic are compared with predictions based on simple-sweep theory applied to the two-dimensional wing section characteristics. The measured transonic drag rise at zero lift is compared with values of-wave drag computed by linearized theory.