vintageNASA7

Looking down the throat of the world’s largest tunnel, 40 by 80 feet, located at Ames Aeronautical Laboratory, Moffett Field, California. The camera is stationed in the tunnel’s largest section, 173 feet wide by 132 feet high. Here at top speed the air, driven by six 40-foot fans, is moving about 35 to 40 miles per hour. The rapid contraction of the throat (or nozzle) speeds up this air flow to more than 250 miles per hour in the oval test section, which is 80 feet wide and 40 feet high. The tunnel encloses 900 tons of air, 40 tons of which rush through the throat per second at maximum speed. (1947) – Courtesy of the awesomeness at Brainpickings.org

vintageNASA6
vintageNASA8