Experiments with Intubed Propellers
This is a 1932 technical report from NASA's Technical Reports Server, a scientific paper on experiments with propellers fitted inside tubes (intubed propellers), written for aeronautical engineers and researchers. Its pictures are plain line graphs on gridded paper, plotting torque and thrust against revolutions per minute and other values, with dashed and solid curves compared side by side. A designer may find little visual use here beyond the grid layouts and the restrained chart typography.
