At about 4:15 p.m. on November 7, 2006, a ramp worker pushing back United Airlines Flight 446 at Chicago's O'Hare Airport saw a dark, metallic, disc-shaped object hovering over gate C-17 and told the flight crew.
About twelve United employees, including pilots, managers and mechanics, saw the object. They said it was silent, dark grey, between 6 and 24 feet across, and hung below the cloud base for several minutes. Witnesses outside the airport said it shot straight up and left a clear blue hole in the clouds that soon closed.
The object did not show on radar and air traffic controllers did not see it. The FAA did not investigate, calling it a weather phenomenon, possibly a hole-punch cloud. The story broke when the Chicago Tribune reported it two months later.