Measurements have been made with new equipment designed for derivative tests in a 9 x 7 ft tunnel, to determine the effect of sweepback on the derivatives for a rectangular aerofoil of aspect ratio 6. Some difficulty was ...

Measurements of the pitching moment derivative coefficients for a 7½ per cent bi-convex aerofoil oscillating about the mid-chord axis were made in a high-speed wind tunnel by the method of decaying oscillations. The tests ...

Measurements of the direct pitching-moment derivatives m and m at transonic speeds for two delta and two swept wing planforms are discussed. The tests were made in the N.P.L. 9½ in. high-speed wind tunnel using slotted ...

Apparatus based on a self-excitation technique has been developed for the measurement of direct pitching-moment derivatives at high speeds, and has proved to function satisfactorily. Measurements have been made at subsonic ...