Aerodynamic effects of a split flap on the spinning characteristics of a monoplane model
This is a 1934 NACA technical note from the NASA Technical Reports Server, a wind-tunnel study of a split flap on a monoplane model's spin behaviour, written for aeronautical engineers. Its pictures are plain engineering drawings: a dimensioned side and plan view of a model wing and tail with split flaps, and a grid of normal-force coefficient curves plotted against angle settings. A designer might take from them only the clean, sparse line-drawing conventions of mid-century technical figures, with dimension callouts and labelled graph axes.
