The Aerodynamic Effects of Wing Cut-Outs
This NASA technical report from 1935 studies how cut-outs in aircraft wings change aerodynamic behaviour, written for aeronautical engineers and researchers. Its pictures pair a photograph of a flat cut-out wing model with line graphs of spanwise lift distribution and downwash angle plotted against distance from the wing centre. A designer could take from them the clean, restrained look of technical engineering diagrams, with dense multi-series plots, fine dashed and dotted lines, and a single sculpted wing silhouette against a plain grey ground.
