A discussion of the several types of two-stroke-cycle engines
A 1935 NACA technical memorandum by the NASA Technical Reports Server collection, issued by the United States government aeronautics research body to engineers working on aircraft engines. The pictures are engineering diagrams: cross-sections of cylinder blocks and front views of V-engines with labelled sections, plus pump and piston schematics and performance curves plotting pressure, speed and fuel consumption against engine rpm. A designer could take from them the clean, labelled line-drawing style of mid-century technical plates, with dense grid charts and annotated callouts.
