NACA-RM-L8H20

Abstract

INTRODUCTION <br>The plain-flap type of 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 lift and lateral-control design parameters. In order to help alleviate this difficulty, the National Advisory Committee for Aeronautics is currently investigating flap-type controls on swept wings with the ultimate objective of obtaining flap and aileron design criterions similar to those available on unswept wings (references 1 to 6). <br>The data presented and discussed herein are the results of a low-speed lift and lateral-control investigation of 16.7-percent-chard plain flaps and ailerons having various spans, spanwise locations, and trailing-edge angles on a tapered low-drag semispan wing having a leading-edge sweep angle of 51.3⁰. The present investigation, which was performed in the Langley 300 MPH 7-by 10-foot tunnel, is an extension of the investigation reported in reference 7. The model used in the present investigation and that reported in reference 7 were essentially the same, differing only in the plan form of the wing tip. The characteristics of the wing in pitch were determined through a large angle-of-attack range for various flap deflections with the flaps sealed and unsealed. Rolling-moment, yawing moment, hinge-moment and internal seal pressure characteristics of the various span ailerons were determined for a large range of aileron deflections and angles of attack with the ailerons sealed. The effect of aileron-end treatment (inboard end of aileron cut off parallel to the plane of symmetry rather than normal to the aileron hinge axis) on the lateral control and hinge-moment characteristics of one of the aileron configurations was also investigated. In addition, the lateral-control effectiveness of a spoiler configuration (previously developed on another sweptback wing, reference 8), investigated in conjunction with a full-span plain unsealed flap deflected various amounts, was determined. <br>Included herein is a comparison between the aerodynamic and lateral control characteristics of the subject wing and the raked-tip wing of reference 7.