Device for the Automatic Control of Airplanes
This is a 1929 NASA technical memorandum on a device for automatically controlling airplanes, issued by the NASA Technical Reports Server collection for engineers and aviation researchers. Its pages are mostly line diagrams of mechanical linkages, gyroscope-driven gears and control circuits, with labelled parts numbered in sequence, plus one photographed instrument with a large handwheel. A designer might take from them the precise, schematic style of early technical drawing, with numbered callouts and thin hairline strokes suited to vintage engineering motifs.
