Force measurements on airplanes
A 1929 NASA technical report on measuring thrust and torque on aircraft propellers, compiled from the NACA-era technical reports archive and written for aeronautical engineers. The pictures are plain engineering line drawings and black-and-white photographs of measuring devices such as hub-mounted transmitters, cylinder assemblies and sectioned propeller couplings, with labelled callouts; a designer might take from them the dense technical-diagram look of numbered callouts, sectional cutaways and grey photographic plates.
