The Parker Variable Camber Wing
A 1920 aeronautical report from the NACA annual report, issued by the National Advisory Committee for Aeronautics for engineers and aircraft designers, presenting test data on the Parker variable camber wing. The pictures are plain black-and-white engineering graphs: ruled grid plots of lift, drag, and centre of pressure against the ratio of wing chord to wind, with hand-lettered legends and curves in solid, dashed, and dotted lines. A designer might take from them the clean chart conventions of early aerodynamic data, with restrained line-and-grid layouts suited to technical infographics.
