Description and Laboratory Tests of a Roots Type Aircraft Engine Supercharger
A 1926 NASA technical report describing and testing a Roots-type supercharger for aircraft engines, written for engineers and aeronautical researchers. Its pictures are plain technical graphs of pressure ratio against drive shaft speed and volumetric efficiency, plus a photograph of a Liberty-12 engine fitted with the supercharger, offering a designer little beyond the engine's dense, mechanical structure and the grid-and-curve chart style.
