Theoretical stability and control characteristics of wings with various amounts of taper and twist
This is a 1938 NASA technical report on the theoretical stability and control of wings, prepared by NASA's aeronautical research staff for engineers and aircraft designers. The three pictures are engineering graphs and outline drawings: line charts of lift-related coefficients against spanwise position, wing planform contours with quarter-chord points marked, and stacked curves of loading distribution across the span, all in plain black ink on white. A designer might take their clean, labelled plotting style and the nested family of curves as a model for dense technical diagrams.
