NACA-RM-L53G09

Abstract

<u>INTRODUCTION</u> <br>As pointed out in reference 1, estimations of the yaw characteristics of a complete airplane should be based, for the most part, on experimental data because of the inadequacy of the present theory for predicting the large interference effects between various airplane components and the large variations of the static stability derivatives with angle of attack which result from flow separation. Investigations made by the National Advisory Committee for Aeronautics on the yaw characteristics of swept wing such as references 2&#160;to 8 provide low-speed data for wing and wing-fuselage configurations. Low-speed static lateral stability derivatives of more complete models are presented at high Reynolds number in references 9 and 10 and at low Reynolds number in references 11 to 15. These data have dealt with wings having an aspect ratio 4 or less with the exception of the thirty wing models of reference 8. <br>In order to provide information on wing of higher aspect ratio, an investigation of an airplane configuration having a 47.7⁰ swept wing of aspect ratio 6 was conducted in the Langley 19-foot pressure tunnel at a Reynolds number of 4.45 x 10⁶ for the purpose of determining (1) the static lateral stability characteristics of a complete airplane model having a swept wing of relatively high aspect ratio, and ( 2) the lateral stability contributions of the main airplane components (wing, fuselage,&#160;vertical and horizontal tail) and the associated mutual interference effects. Particular reference is made to the vertical-tail effectiveness. c. In addition to determining the contribution of the main airplane components, the effects of leading-edge flaps, trailing-edge flaps, and fences on the lateral stability characteristics were investigated Brief studies of the effects of fuselage length and Reynolds number were also mad.