Abstract: Airfoil device and method providing smooth, continuous, variation in airfoil camber and surface curvature over substantially the entire length of the device by use of a trusslike bendable beam as an airfoil rib having the airfoil skin surfaces flexibly slidable relative thereto. The beam is divided chordwise into upper and lower beam members each formed of a plurality of articulated sections. The beam members are connected by a bendable jackscrew which upon rotation causes one member to move chordwise, and its curvature to be changed, relative to the other thereby effecting deflection of the airfoil with concomitant variation in its camber and the curvatures of its outer skin surfaces.

Abstract: An aircraft wing box construction including canted sheet metal spar webs continuously tied to the upper and lower skins. Sheet metal intercostal stiffeners of substantially triangular configuration are spaced spanwise along the web to provide shear stiffening for the web and intermittent stabilization for the upper skin. Both the shear web and intercostal stiffeners are fastened to spanwise continuous spar caps which are attached to the upper and lower skins. These caps, supported by the intercostals and webs, provide sufficient stabilization to prevent upper skin buckling up to ultimate design stress with a minimum of shear webs thereby providing significant weight savings.