Aviation aux Etats-Unis : amélioration technologique et sécurité, 1930-1939. - 24 photos - Photo n° 228646
Photo n°
228646
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WATCH YOUR CREDIT LINE: PHOTO FROM WIDE WORLD PHOTOS: 692682-A PROTECTION FOR THE NIGHT AIRMAN. PITTSBURGH, PA.-An “obstruction marker” has been placed forty floors above the ground on top of the new building of the University of Pittsburgh. It has been put there temporarily by the Westinghouse Electric and Manufacturing Company to demonstrate the protection it affords tall unlighted obstructions at night from strange or low flying confused aircraft. It distinctive ball of red light about three feet in diameter can be seen from a distance of five miles on a clear night. 5-19-30 [Actualit-G.Champroux] [Leihweise - Wide World Photos- Berlin]
