Wing resistance near the ground
This is a 1922 aeronautical technical report from the NASA Technical Reports Server, a government aerodynamics paper on how wings behave close to the ground, written for engineers and researchers. The pictures are plain graphs of coefficients and lift curves plus a schematic of a wing above its mirror image, drawn in black line on white with fine gridlines. A designer might take from them the simple vocabulary of technical plotting: labelled axes, curve families with small markers, and clean diagrammatic arrows and dashed reflections.
