The Synchronization of NACA Flight Records
A 1922 NACA technical report on synchronizing flight records, issued by the aeronautics research agency for engineers and instrument makers. The two pictures are line drawings of mechanical apparatus: a schematic of a winding motor with contacts, and an isometric view of a film drum with a timing light and slit. A designer could take from them the clean, labelled technical diagram style of early engineering documentation, with thin uniform outlines, boxed schematic blocks and leader-line callouts.
