Effect on hinge moment of fitting strips near aileron trailing edge, of increasing aileron chord and of extending aileron to wing tip with an appendix on pressures over surface of control fitted with strips

Abstract

To find a method Of modifying ailerons so that a machine may be more responsive in roll. (1) Hinge moment was measured on a 1/2.25 scale 'Hurricane' aileron with the following modifications:- (a) Strips (depth 0.02 in. and 0.04 in.) fitted near trailing edge. (b) Aileron chord increased from 0.18c to 0.22c and 0.26c. (c) Aileron chord 0.22c, extended to the wing tip. Strips (depth 0.04 in.) also fitted near trailing edge. Range of aileron angle 0° to ±15° ; Range of incidence -4° to 8°. (2) Pressures were measured over the surface of a control (0.4c) of an aerofoil (N.A.C.A. 0020 section, 30 in. chord) with and without strips (depth 0.05 in.- 0.20 in.) or cords (0.09 in. diameter) by means of a static pressure tube : Angles of incidence 0°, 4° and 8°. Control angles ±10° and ±15°.