Aerodynamic Characteristics of Airfoils at High Speeds
This is a 1925 NASA technical report on airfoil aerodynamics at high speeds, prepared for aeronautical engineers and researchers. Its pictures are plain engineering graphs on grid paper: lift coefficient plotted against speed ratio and against drag, with labelled curves for different airfoil shapes and angles of attack. A designer could take from them the restrained, diagram-based vocabulary of technical charts, with clean grids, labelled curve families and small numeric tick marks.
