O'HARE

Opening

Just after 4:15 p.m. on 7 November 2006, a United Airlines ramp worker at Chicago's O'Hare International Airport noticed a dark grey, disc-shaped object hovering silently over Gate C17. Within minutes at least twelve United employees, including pilots, supervisors and mechanics, were watching it. After about five minutes it shot straight up through the overcast and, several witnesses said, left a clear blue hole in the cloud that closed soon afterwards. Nobody in the control tower saw it, and nothing was reported on radar. The public heard nothing until New Year's Day.

Timeline

7 November 2006, about 4:15 p.mA ramp worker pushing back United Flight 446, bound for Charlotte, North Carolina, from Gate C17, spots the object and radios it in. The crew of the plane are told and look up too. The object is seen over Concourse C. Witnesses estimate it at between 6 and 24 feet across, metallic and silent, below a low cloud deck.

About 4:20 p.mIt accelerates upward through the clouds. A United supervisor calls an FAA manager in the tower to report it. Some people outside the airport also report a sighting.

Following weeksAsked by the Chicago Tribune, both United and the FAA say they have no information.

Before publicationA Tribune Freedom of Information Act request turns up the recorded call from the United supervisor to the tower.

1 January 2007Transportation reporter Jon Hilkevitch's story runs on the Tribune's front page: "In the sky! A bird? A plane? A ... UFO?" It goes national within days.

January 2007The FAA calls it a weather phenomenon and says it will not investigate.

2007NARCAP, a group studying unexplained aerial phenomena and aviation safety, publishes a 154-page report on the sighting by Richard Haines and colleagues, titled "Report of an Unidentified Aerial Phenomenon and its Safety Implications at O'Hare International Airport on November 7, 2006." It treats the case as a safety question, not an alien one.

Key figures

The witnesses were United Airlines staff, most of whom spoke to the Tribune only anonymously. Jon Hilkevitch broke the story and found the tape. Astronomer Mark Hammergren of Chicago's Adler Planetarium suggested a hole-punch cloud. Richard Haines led the NARCAP study, which focused on the safety question of an unknown object hovering over a busy airport.

Physical and documentary trail

What survives: the FAA tape of the supervisor's call, Hilkevitch's interviews, and the NARCAP report. The tape confirms that a sighting was reported in real time. It doesn't show what was seen.

Still missing: any photograph or video, any radar return, and any explanation from United for why it first said it had no information. The witnesses also disagreed on the object's shape, height, movement and even how many objects there were.

Things you might not know

• It broke the Tribune's website. Hilkevitch's story drew more than a million hits, a traffic record for the paper's site at the time.
• The tower saw nothing. The controllers in one of the world's busiest towers, with a clear view of the concourse, did not see the object.
• The cloud hole is the detail people remember. Witnesses described a clean-edged blue hole, as if something had punched through, that closed again within minutes.
• It got its own TV episode. The History Channel's UFO Hunters covered it in "Aliens at the Airport" in February 2009.
• It reached prime-time drama. The sighting was referenced in an episode of Boston Legal and inspired the 2018 film UFO.
• The security question was raised. UFO researchers argued that the FAA's refusal to investigate clashed with its duty to look into anything that might threaten airport safety.

Competing explanations

A hole-punch cloud. A real weather effect: supercooled water in a cloud layer suddenly freezes and falls, often triggered by a passing aircraft, leaving a round gap. It explains the hole. It doesn't explain a dark disc seen hovering below the clouds for five minutes beforehand.

A misidentified ordinary object. A balloon, a bird or a reflection seen against a grey sky, made more convincing as more people joined in. The disagreements between witnesses fit this reading. The witnesses' daily work around aircraft makes it harder to accept.

An unidentified object. Twelve aviation workers reported something solid and silent over a gate at one of the world's busiest airports, and it was never identified.

Later life of the case

O'Hare is the standard modern example of airline staff reporting a UFO, and NARCAP's report is still cited in the debate about whether pilots and ground crew should be encouraged to report what they see. That debate is now part of US government UAP policy.

Finding

Something was seen over Gate C17 by a dozen United employees, and the FAA's own tape shows it was reported at the time, despite both the airline's and the agency's first denials. A hole-punch cloud is a good fit for the hole, but not for the object.

What still will not resolve: what the witnesses saw hovering before the hole appeared. No photograph or radar track has ever surfaced.