Correcting engine tests for humidity
This is a 1929 NACA technical note, published by the National Advisory Committee for Aeronautics in the United States, on correcting aircraft engine test results for atmospheric humidity, written for engine researchers. The pictures are plain technical charts: a nomogram with scaled axes and curved construction lines, a grid plot of loss of indicated power against loss of oxygen content with data points and fitted lines, and a fuel consumption chart with two curves of brake horsepower and specific fuel consumption. A designer might take their clean monochrome line work, dense tick-marked scales and tabular grid structure as a source for technical diagram layouts.
