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Blowing the wind.

May 27, 1931: Wind Tunnel Lets Airplanes ‘Fly’ on Ground

In a massive building covering more than two acres, the wind tunnel used a pair of 35-foot propellers connected to 4,000-horsepower electric motors. Air was sucked through large funnel-like structures that directed a smooth flow of air past the staging area where airplanes, helicopters, race cars and even a Navy SEAL submarine were tested.