The velocity distribution caused by an airplane at the points of a vertical plane containing the span
A 1925 technical report from the NASA Technical Reports Server, a mathematical study of the air velocity an airplane produces at points in a vertical plane through its span. The one figure is a line diagram of a rotating arm of length R at angle φ above a horizontal baseline, with distance a marked from a vertical axis, a schematic for aerodynamic calculation rather than an illustration for display. A designer might take its clean dimensioned line drawing style and technical labelling conventions as a model for diagrams.
