A general tank test of a model of the hull of the Pem-1 flying boat including a special working chart for the determination of hull performance
This is a 1938 NACA technical report, issued by the NASA Technical Reports Server, presenting tank test results for a scale model of a flying boat hull for aviation engineers and naval aircraft designers. The pictures are dense engineering line charts: plotted curves of resistance, trim and speed coefficients over grids, with many labelled families of lines and small numbered markers. A designer might take from them the look of technical graph paper, with clean grid lines, sparse colour and tightly packed curve families.
