Autogenous welding in airplane construction
A 1929 NACA technical memorandum on autogenous welding in airplane construction, issued by the National Advisory Committee for Aeronautics for aircraft engineers and builders. Its plate is a grid of nine black-and-white photographs of welded metal airframe joints, struts and fittings, each labelled Fig. 1 through Fig. 9. A designer could take from it the look of early industrial aircraft structure: lattice trusses, tubular frames and workshop close-ups.
