Skins from the Solid: Some Notes on Recent Developments in the Production of Wing Structures

ONE of the most fundamental structural problems created by the advances in aircraft design during the past few years is that of the wing which is becoming progressively thinner and more highly loaded, and also demands higher degrees of surface finish, with accurate maintenance of contour throughout the load range. Stiffness becomes as important as strength, and the use of large angles of sweep‐back introduces the problem of torsional stiffness to a much greater degree than before. The natural result is that more and more of the load‐bearing part of the wing structure has to be placed in the surfaces of the aerofoil; the development from a fabric‐covered rib and spar structure to one in which the skin carries load, stressed‐skin construction that is, has to be carried further. The increased loadings necessarily increase the amount of structural material in the wing, so that skins can become thick enough to bear a high proportion of the load without buckling, the ultimate development being an aerofoil having two thick skins, with a light internal structure to help carry the shear stresses; this might be a honeycomb.