BOEING’s “AQUA-JET” HYDROFOIL RESEARCH HYDROPLANE
From 1961-1966, the Boeing owned and operated Aqua-Jet provided a continuous “water tunnel” between its sponsons in which to measure the hydrodynamic parameters of many small, scale model hydrofoil “wings” of different designs at various angles of attack, depths and speeds. The instrumentation was such that a complete “polar” plot (of lift and drag versus angle of attack at any one foil depth and speed) could be obtained in a run time of only 30 seconds!
(Source: foils.org)