A study of factors affecting the steady spin of an airplane
A 1933 NASA technical report on factors governing the steady spin of an airplane, prepared for aeronautical engineers and researchers. Its pictures are engineering graphs plotting rolling-moment, pitching-moment and wing-tip angle-of-attack coefficients against angle of attack, with labelled curves for spin-angle values; a designer might take from them the clean, sparse plotting style of mid-century technical charts.
