Book Description

An investigation has been conducted in the Langley full-scale tunnel to determine the aerodynamic characteristics of a full-scale model employing a sailwing concept and having a wing aspect ratio of 11.5. The wing had a rigid leading-edge spar, rigid root and wing-tip ribs with a trailing-edge stretched between these ribs, and a fabric covering stretched between the leading and trailing edeges. The fabric of the sail maintained a smooth airfoil contour over the installed angle-of-attack range, but some rippling occurred at the trailing edge near the wing root as the wing stalled. The aerodynamic characteristics of the sailwing, in particular the maximum lift and maximum lift-drag ratio, compared favorably with those of conventional hard wings. A lateral-control device based on the wing-warp principle was effective at angles of attack below that for wing stall, but at angles near stall, the control effectiveness became low and nonlinear.