Effect of retractable-spoiler location on rolling- and yawing-moment coefficients
A 1934 NASA technical report, published by NACA-era aerodynamics researchers for aeronautical engineers, measuring how retractable spoiler placement on an airfoil changes rolling and yawing moments. Its pictures are line diagrams of airfoil profiles at angles of attack from 0 to 20 degrees, with curved contour lines of spoiler-induced pressure coefficients and dashed construction arcs marking spoiler positions in chord fractions. A designer could take their clean, labelled graphic language of stepped contour families and dimensioned arcs as a model for technical diagramming.
