The O'Hare Airport UFO sighting

On 7 November 2006, United Airlines workers at O'Hare Airport in Chicago reported a spinning disk hanging below the clouds over Concourse C.

Skeptoid's Brian Dunning says a ground crewman looked straight up and saw a dark gray disk spinning silently just under the cloud base, which sat at about 1900 feet. He called the duty manager on the radio, and United staff across the airport who heard the call looked up.

WTTW's Chicago Mysteries with Geoffrey Baer says over a dozen workers saw it. Pilots, mechanics, baggage handlers and air traffic controllers were among them. Chicago Tribune transportation reporter Jon Hilkevitch investigated, and the employees' accounts matched. The New Yorker's Gideon Lewis-Kraus adds that the object stayed put for a few minutes, then shot away at a steep angle, and one anonymous witness described a nearly round hole left in the cloud.

United Airlines and the FAA at first said they had no information about it, Wikipedia records, until the Tribune made a Freedom of Information Act request. An FAA review of air traffic tapes then turned up a call in which a United supervisor told a manager in the FAA tower about it. When the Tribune ran the story, no witness would give their name, and the piece drew more readers than any earlier story on the paper's website, according to The New Yorker. In a 2013 look back, the Tribune's RedEye counted it among the decade's most publicised sightings.