Abstract:
Some oscillatory aerodynamic derivatives for wing pitch and translation, and control-surface rotation have been found from measurements in a low-speed wind tunnel. The wing was a modified cropped delta of biconvex circular-arc section having a small leading-edge radius and fitted with a horn-balanced control surface. The measurements covered a range of control-surface angles with the wing at a mean angle of incidence of 0% Control-surface setting influenced the values of all derivatives but the variation was small for angles in the range 0° to 5°. The wing lift and pitching-moment derivatives for wing motion at small control angles were in satisfactory agreement with theoretical results. Derivatives for control-surface rotation at small angles of the control were generally in reasonable agreement with values estimated using theoretical and semi-empirical methods.
