Jack Cotter inspects an aircraft model in the Icing Research Tunnel.
In this historical photo from the U.S. space agency, Jack Cotter inspects a Commuter Transport Engine undergoing testing in the Icing Research Tunnel while Ray Soto looks on from the observation window in January of 1983.
The Icing Research Tunnel, or IRT, is used to simulate the formation of ice on aircraft surfaces during flight. Cold water is sprayed into the tunnel and freezes on the test model.
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