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This note describes further tests made during 1954 in the Royal Aircraft Establishment 10 ft x 7 ft High Speed Tunnel, as part of a research programme to improve the subsonic longitudinal stability characteristics of a 50 deg swept wing of aspect ratio 3" 1 by means such as nose-droop, chord extensions, fences, change of aerofoil section, etc. Lift, drag, pitching-moment and root bending moment were measured with the basic 7½ per cent thick RAE 101 section, with a symmetrical blunt-nosed NACA 3-007.5 section, and with a full-span drooped and thickened nose, at Mach numbers up to 0"94 and Reynolds numbers between 1-7 x 106 and 6 x l0 G. The main conclusions are as follows: (i) None of the section changes gives any advantage over the basic RA_E 101 section at the highest test Mach numbers. (ii) The drooped-nose sections are superior to the NACA 3-007.5 section at all Mach numbers. (iii) The full-span nose-droop is inferior to the part-span droop with the same section tested earlier in the series: (iv) Better high-speed characteristics should be obtainable by the use of nose-droop without the thickening applied here. Further conclusions are given in Section 5. Oil-film flow patterns show several interesting features which are discussed in some detail. Another feature which is discussed is the occurrence of an unusual adverse scale effect on the drooped wings at low Mach number. 1. Introduction. Refs. 1 to 3 describe tests in the R.A.E. 10 ft x 7 ft High Speed Wind Tunnel t at Mach numbers up to 0.9~ on a 50 deg swept wing with an aspect ratio of 3-1 and a 7½ per cent thick RAE 101 section, with and without stall-fences, part-span leading-edge extensions and part-span leading-edge droop and thickening. One of the objects of these tests was to investigate and improve the pitching-moment behaviour at moderate and high lift coefficients, since on the basic wing the useful C L range is restricted by loss of stability due to outer-wing flow separation. The various devices gave some increase in the C L for instability but the improvement was less than hoped for, particularly at the higher subsonic Mach numbers.