Relative loading on biplane wings
This is a 1934 NACA-style technical report from the NASA Technical Reports Server on relative loading of biplane wings, written for aeronautical engineers and aerodynamics researchers. Its pictures are plain engineering graphs drawn on squared grids, with labelled curve families of correction factors, stagger angles, and decalage angles plotted against wing geometry. A designer could take from them the restrained visual language of mid-century technical charting: dense grid paper, thin dashed and solid curves, and small italic axis labels.
