A McDonnell Douglas MD-82 making a turn under the direction of an air-traffic controller crossed in front of a Boeing 767, the FAA said.
The two planes, at the closest point, were at the same altitude and only 0.35 miles apart laterally, according to a preliminary FAA review of radar data.
Because of an error by the controller working O'Hare traffic from the FAA's radar facility in Elgin, the MD-82 "overshot the final approach course for runway 28'' and encroached on the airspace restricted for use by the 767 that was on a straight-in approach to runway 27 Left, according to the FAA and the NTSB.
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