D.H. 86 "Express Air Liner" (British) : a four-engine biplane
This 1934 record is a technical circular from the National Advisory Committee for Aeronautics, a US government aeronautics body, describing the British de Havilland D.H. 86 Express four-engine biplane airliner for engineers and aircraft designers. The pictures are line drawings and grainy halftone photographs of cabin interiors, pilot's cockpit, undercarriage shock absorbers, and control-surface diagrams, useful to a designer as clear period technical illustration of aircraft mechanical detail and passenger cabin layout.
