The Avro 627 "Mailplane" (English): A Single-Seat Biplane
A 1931 NACA Aircraft Circular from the NASA Technical Reports Server, issued as a technical reference for engineers and aviation students, documenting the Avro 627 single-seat mailplane biplane. The page is a set of orthographic drawings (side, plan and front views) with a dimension table for wing area, aileron, stabilizer, elevator and rudder, plus a caption giving the general arrangement of the aircraft powered by an Armstrong Siddeley Jaguar engine. A designer could take its clean technical line drawing style, with fine dimension lines, labelled call-outs and a grid-like layout, as a model for precise diagrammatic work.
