Experiments on a Slotted Wing
A 1939 NASA technical report on experiments with a slotted wing, issued as a government aeronautics memorandum for aerodynamics engineers and researchers. Its pictures are engineering charts: line graphs of force coefficients plotted against angle of attack, three-dimensional curve plots of pressure, and grids of small pressure profiles at a slot exit. A designer could take from them the restrained, grid-based graphic language of technical plates, with thin black curves, dashed and solid line variants, and labelled axes.
