NASA NACA-RM-L8D30

Abstract

INTRODUCTION <br>In order to provide large-scale data on the high-angle-of-attach characteristics of wings having airfoil sections with sharp leading edges, an investigation is being conducted in the Langley full-scale tunnel at high Reynolds numbers and low Mach numbers of several typical transonic and supersonic swept and unswept wing plan forms having 10-percent-thick, circular-arc airfoil sections. One of the wings investigated was a trapezoidal wing of aspect ratio 4, and the maximum-lift and stalling characteristics have been reported in reference 1. The results of reference 1 show that the inherently low maximum lift and high drag of the wing were appreciably improved when a drooped-nose flap was deflected. Inasmuch as this type of high-lift device was found to be effective, a more complete study was made of several leading-edge high-lift devices as a part of a general investigation conducted on a rectangular wing of aspect ratio 3.4 with 10-percent-thick circular-arc airfoil sections. This wing is identical to the wing tested in reference 1 except that the tips were modified so as to form a rectangular plan form. <br>The investigation included measurements at high Reynolds numbers and low Mach numbers of the aerodynamic characteristics in pitch and in yaw of the basic wing and of the wing with several leading-edge high-lift devices and 0.20-chord split flaps deflected both alone and in combination with one another. The leading-edge high-lift devices investigated included a 0.20-chord drooped-nose flap, a 0.10-chord extensible leading-edge flap, and several simulated round leading edges. The scale effect on the aerodynamic characteristics was determined for a range of Reynolds numbers from about 2.9&#160;x 10⁶ to 8.4&#160;x 10⁶. In addition to the force measurements, the stalling characteristics of the wing and without high-lift devices were determined by means of tuft observations.