What happened
Shortly before midnight on July 19, 1952, air traffic controllers at Washington National Airport noticed seven unidentified targets on radar. The returns were confirmed by radar at Andrews Air Force Base, and airline pilots reported strange lights. The objects appeared and disappeared for several hours, passing over the White House and the Capitol as well. Toward morning F-94 fighters arrived but saw nothing unusual. A week later, on the night of July 26–27, the scene repeated itself: this time one of the pilots reported that he was surrounded by lights. The story made front pages, and on July 29 General John Samford held the Pentagon’s largest press conference since the war.
Witnesses
Air traffic controllers at Washington National Airport, including senior controller Harry Barnes, personnel at Andrews Air Force Base, civilian and military pilots.
Explanations and hypotheses
The Air Force announced that the false radar returns and the lights were caused by a temperature inversion over the city, typical of a hot summer. Some controllers and a number of scientists disputed this explanation, pointing to the agreement between visual and radar observations. The Washington wave prompted the CIA to convene the Robertson Panel in 1953, which recommended reducing interest in the subject.
Disputed A likely explanation exists, but some of the facts are still disputed.
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