A Comparison of Several Methods of Measuring Ignition Lag in a Compression-ignition Engine
This 1934 NACA technical note, issued by the National Advisory Committee for Aeronautics, compares several ways of measuring ignition lag in a compression-ignition engine, written for engine researchers. Its pictures are plain technical plates: a line graph of effective fuel burned against crankshaft degrees, pressure-time curves, a schematic of the indicator and stroboscope set-up, and a photograph of the test engine with its auxiliary apparatus. A designer might take the clean monochrome charts and labelled schematics as a model for restrained, functional scientific diagramming.
