NACA-RM-L8H10

Abstract

INTRODUCTION <br>Estimation of the dynamic flight characteristics of aircraft requires a knowledge of the forces and moments resulting from the angular motions of the airplane. The relationship between the forces and moments and the angular motions of the airplane are commonly expressed in no dimensional terms know as the rotary derivatives. In the past these rotary derivatives have generally been estimated from theory because of the lack of a convenient experimental technique. <br>The recent application of the rolling-flow and curved-clown principles of the Langley stability tunnel (references 1 and 2), however, has made the determination of the rotary derivatives relatively easy. A systematic research program utilizing these new experimental techniques has been established to determine the effects of various geometric variables on both rotary and static stability characteristics. <br>The present investigation was made to determine the effects of airfoil profile of symmetrical sections on the low-speed static and yawing chacteristics of sweptback wings. One of the wigns having a blunt leading edge was tested with and without a nose spoiler extending from the plane of symmetry to the 50-percent semispan of either wing panel to determine whether there might be any advantage in a wing with the section varying from sharp nose at the wing root to round nose at the wing tip. The effect of increased turbulence on the aerodynamic characteristics of the wings in straight flow was investigated. Comparisons of some of the experimental results with theory are also presented.