Pressure-plotting and force tests at mach numbers up to 2.8 on an uncambered slender wing of p = .50, S/Co = .25 'handley page ogee'

Abstract

Pressure-plotting and force tests have been made in the 8 ft x 8 ft Wind Tunnel, Bedford, on an uncambered slender wing of Collingbourne p = ½ ogee planform, s/c o = 0.25, 'Newby' area distribution, and varying cross-section shape representing an aircraft with a central passenger cabin blending into the wing. The model is one of two designed by Messrs. Handley Page under the auspices of the Supersonic Transport Aircraft Committee. At zero rift, the wave-drag factor K 0 is about 0.2 below the slender-theory value at all Mach numbers, due to the absence of a predicted rapid expansion towards the trailing edge, and further work on sting interference seems desirable. Apart from the difference near the trailing edge, the measured zero-lift pressures are in quite good agreement with slender or linear thin-wing theory. At incidence, the pressure gradients are everywhere favourable behind the leading-edge vortex, and there is a large trailing-edge load which is not predicted by slender theory. The cruising centre of pressure is 0.075co behind the low-speed aerodynamic centre at C L = 0.5. At M = 2.2, K 0 is 0.72 and the lift-dependent drag factor is 1.92, giving an estimated full-scale maximum L/D of 8.3 excluding engines.