Determination of Stresses and Deformations of Aircraft Propellers
This is a 1932 NACA technical memorandum on aircraft propeller stress and deformation testing, issued by the NASA Technical Reports Server collection for engineers and aeronautical researchers. Its two photographs show an experimental test rig with a propeller mounted on a frame in a workshop, plus a close-up of the blade hub and its clamped mounting. A designer might take from them the plain industrial look of early laboratory apparatus: bare timber frames, exposed fixtures, and a pale propeller blade set against dark walls.
