The Drag of Streamline Wires
This is a 1933 NACA technical report from the National Advisory Committee for Aeronautics, issued as a government research note on the drag of streamline wires for aircraft designers and engineers. The pictures are plain, unornamented engineering figures: wire cross-section profiles plotted against inches, a graph of drag coefficient against Reynolds number with labelled curves, and smoke-flow photographs of air passing around a lenticular section with and without protuberances. A designer could take from them the teardrop and lens section shapes, and the streamlines that show how airflow separates from a body.
