Aerodynamic theory and test of strut forms. Part I
This is a 1930 NACA-style technical report, Part I of a study on aerodynamic theory and wind-tunnel testing of aircraft strut cross-sections, issued for aeronautical engineers and researchers. Its pictures are plain engineering line graphs: curves of velocity and pressure plotted against strut width or thickness, comparing experimental measurements with theoretical predictions, with dashed and solid lines, labelled axes and legends. A designer could take from them the restrained chart vocabulary of the period, with its paired curve styles, open and filled plot markers, and dense axis labelling.
