The reduction of airplane flight test data to standard atmosphere conditions
A 1926 technical report from the NASA Technical Reports Server, apparently issued by the National Advisory Committee for Aeronautics, on converting airplane flight test readings to standard atmosphere conditions for engineers. The two pictures are graph plates: one a family of altitude-pressure curves labelled in feet against inches of mercury, the other a pair of altitude curves plotted against air density ratio. A designer might take from them the clean, dense grid-and-curve vocabulary of early engineering charts, with fine black lines on white and small italic labels set along the axes.
