Triplane tests
A 1924 technical report from the NASA Technical Reports Server, a record of wind-tunnel tests on triplane wing arrangements, presumably written for aeronautical engineers and researchers. The pictures are line diagrams of three stacked airfoil sections with dimension letters, and fanned sets of angle-of-attack lines drawn from a common pivot, showing how each wing's incidence was varied; a designer could take from them a clear schematic vocabulary for layered wing layouts and angle sweeps.
