Tests in the R.A.E. 10-ft x 7-ft high speed wind tunnel on drop tanks fitted to two swept-back wings Part 1 Comparison of under-wing and wing-tip installations Part 2 Comparison of various under-wing drop-tank arrangements

Abstract

The report describes tests made in the Royal Aircraft Establishment 10-ft × 7-ft High Speed Wind Tunnel on drop tanks, fitted to two wings, having the same plan-form with a sweepback of 40 deg and an aspect ratio of 3.5, but differing in thickness/chord ratio, being 10 per cent and 8.5 per cent thick respectively. Part I compares the results obtained with the drop tanks mounted in two alternative positions on the 10 per cent thick wing : under the wing at about mid-semi-span, supported by an 8.5 per cent thick strut or alternatively, at the wing tip in a mid-wing position. Part II compares the results obtained with several different types of under-wing installation, e.g., with different designs of strut or alternatively dispensing with the strut and fitting the tanks directly on to the lower surface of the wing. The latter are referred to as 'nacelle-type' tanks. Most of the tanks had a fineness ratio of 8 : 1.