Casualties unknown

1986-05-17: Mcdonnell Douglas DC-9-31 (N973VJ) — Chicago, IL

Chicago, IL, US

On May 17, 1986, a Mcdonnell Douglas DC-9-31 (registration N973VJ) was involved in an aviation accident near Chicago, IL. Investigators recorded the probable cause as: The local controller inadvertently forgot he had cleared U.S. Air Flight 373 for takeoff and then cleared American Airlines Flight 695 for takeoff approximately 20 seconds later. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A U.S. Air flight and an American Airlines flight came within 20 feet of each other during takeoff at Chicago O'Hare after a controller inadvertently cleared both from intersecting runways.

Incident Overview

On an unspecified date, U.S. Air Flight 373 and American Airlines Flight 695 were both taking off from Chicago O'Hare International Airport. The two aircraft converged at the intersection of Runway 32R and Runway 4L. During this event, they came within approximately 20 feet of each other. Both flights had been cleared for takeoff by the local controller at O'Hare Tower.

Controller Actions

The local controller was simultaneously providing additional severe weather avoidance (SWAP) clearances. In the process, he inadvertently forgot that he had already cleared U.S. Air Flight 373 for takeoff. About 20 seconds later, he cleared American Airlines Flight 695 for takeoff. The clearance of the second flight occurred while the first aircraft was still on the runway, leading to the close proximity between the two aircraft.

Proximity and Runway Configuration

Runway 32R and Runway 4L intersect at O'Hare International Airport. Both aircraft were engaged in takeoff roll when U.S. Air Flight 373 passed over American Airlines Flight 695 at the intersection. The vertical separation between the aircraft was reported as 20 feet. No collision occurred, and the event concluded without further incident.

Probable cause

The local controller inadvertently forgot he had cleared U.S. Air Flight 373 for takeoff and then cleared American Airlines Flight 695 for takeoff approximately 20 seconds later.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X33516. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.