Probable cause
The air traffic controller’s failure to adhere to runway separation requirements and his issuance of an improper takeoff clearance. Contributing to the incident was the controller's failure to recall that there was an arrival inbound to a crossing runway.
NTSB analysis
A near-midair collision occurred between a Bombardier CRJ2 landing on runway 9R and an Embraer ERJ-145 regional jet departing from runway 32L. The CRJ2 passed 480 feet behind and 275 feet above the ERJ-145. According to the tower air traffic controller responsible for operations on runway 32L, he scanned the final approach course for runway 9R to look for conflicting traffic and saw the approaching CRJ2. However, he then forgot about the arrival and cleared the ERJ-145 for takeoff. The controller was unable to provide any explanation for the lapse. The airport was not equipped with automated assistance for detecting conflicts between departures and arrivals on crossing runways such as these.
Text from the NTSB. Open the NTSB docket for OPS11IA552 for the full record.
Event
- Date
- May 16, 2011
- Type
- Incident
- Place
- Chicago, Illinois
- Nearest airport
- Chicago O’Hare International (KORD)
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.