Boulton Paul p.71A commercial airplane (British) : a two-engine biplane
This is a 1935 NACA aircraft circular from the NASA Technical Reports Server, a technical report issued for engineers and aircraft designers, documenting the Boulton Paul P.71A, a British two-engine biplane. The three pictures are plate sheets of engineering drawings: a general arrangement with top, side and front views, and exploded structural details of the wing, fuselage and fittings, all in fine black line on white paper. A designer could take from them the clean, orderly style of mechanical line drawing, with labelled callouts and dimension lines that read clearly at small size.
