NACA-RM-L8F29

Abstract

INTRODUCTION <br>The plain-flap type of lateral-control device is being considered and incorporated in the design of high-speed aircraft having swept wings. The design engineer on such aircraft is greatly hampered, however, by a lack of data upon which to base estimates of the various aileron-design parameters at high sweep angles. In order to help alleviate this difficultly, the National Advisory Committee for Aeronautics is currently investigating ailerons on highly swept wings with the ultimate objective of obtaining aileron-design data similar to that available on unswept wings (references 1 to 3). Because no adequate theory is yet available for determining aileron effectiveness on swept wings, such as is available for unswept wings, the experimental approach is being followed in these investigations. <br>Previous analyses (such as reference 1) have indicated that the effects of airfoil section on control-surface characteristics result principally from variations in the trailing-edge angle of the control surface. In order to simulate approximately the effects of airfoil section or of fabric deflection on control-surface characteristics, three trailing-edge angles were investigated in the present paper. <br>The data presented and discussed herein are the results of low-speed lateral-control tests of nine different 16.7-percent-chord sealed-plain-aileron configurations (three spans, each with three trailing-edge angles) on a tapered low-drag semispan wing having 51.3⁰ sweepback at the leading edge. The rolling-moment and yawing-moment characteristics, as well as the hinge-moment and internal-seal-pressure characteristics, of each of the configurations are presented for a large aileron-deflection range and angle-of-attack range. The characteristics of the wing in pitch, with the various span aileron to simulate symmetrical sealed-flap configurations, were determined in the course of obtaining the lateral-control data and are also presented and discussed herein. The tests were performed in the Langley 300 MPH 7- by 10-foot tunnel.