Transport: Spinning Tunnel

Each year to Langley Field, Va. go some 300 of aviation’s biggest wigs for the annual engineering conference of the National Advisory Committee for Aeronautics. Each year they see what new and wondrous phenomena the world’s leading aeronautical laboratory has evoked in the twelvemonth past.

Last week, for the Committee’s tenth conference, expectancy ran unusually high. Its chairman, Dr. Joseph Sweetman Ames, president of Johns Hopkins University, had just received from Chancellor Charles Evans Hughes of the Smithsonian Institution aviation’s highest technical award—the Langley Gold Medal for Aerodromics, previously awarded only six times since its establishment in 1908.*

No. 1 surprise for this year’s conference turned out to be a “free-spinning” vertical wind tunnel, first in the U.S. The huge, upended cylinder is 15 ft. in diameter, has an observation platform surrounding it, a propeller to furnish a 50-m.p.h. blast of air. Some 300 pairs of eyes, including Col. Lindbergh’s, fairly popped as they watched a 3-1 scale model demonstrate how an airplane behaves in the dreaded tailspin.

The model was balanced on a pin atop a long pole in the centre of the tunnel. Then an uprush of air whirled the little plane around until it was spinning free. What happened after the pole was removed left observers spellbound. Clockwork mechanism in the model’s fuselage, set in advance, was timed to actuate the controls and set tiny lights flashing if the the cockpit. The model’s ingenious efforts to recover from the spin began in orthodox fashion, with reverse rudder. Simultaneously, a green light flashed. Then a red light flashed, and the flippers flopped down for the nose dive and pullout.

For all its ingenuity, the little plane failed to come out of the spin, plunged instead into a net. So impressive was the demonstration, however, that the Navy Bureau of Aeronautics decided to use the tunnel to determine spin characteristics of its new Grumman Fighter, before permitting that risky ship to be flown by any more test pilots (see above).

*Past winners: Orville and Wilbur Wright jointly in 1909; Glenn Curtiss, Gustave Eiffel, 1913; Charles Lindbergh, 1927; Charles Matthews Manly (posthumously), Richard Evelyn Byrd, 1929.