The Way to Increased Airplane Engine Power
A 1939 NASA technical report on raising aircraft piston engine output, issued as a technical reports server record with no named illustrator, aimed at engineers and aviation researchers. Its pictures are plain line charts and graph paper plots of power against cylinder size, supercharge pressure, compression ratio and engine speed, with lettered curves and hatched bands. A designer could take from them the clean, restrained vocabulary of mid-century technical graphs: fine grid rules, labelled sloped lines, and stepped scales.
