Mcdonnell Douglas MD80 and Boeing 767 incident near Chicago, Illinois, June 1, 2009
On June 1, 2009 at about 5:16 pm local time, 2 aircraft, Mcdonnell Douglas MD80 and Boeing 767, were involved in the same incident near Chicago, Illinois (Chicago O'Hare International airport). No one was hurt; 324 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The Chicago TRACON West Arrival controller's omission of a required clearance, resulting in AAL 879 overshooting the final for runway 28 and losing separation with AAL 93.
The Chicago TRACON West Arrival controller's omission of a required clearance, resulting in AAL 879 overshooting the final for runway 28 and losing separation with AAL 93.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 1, 2009 · about 5:16 pm local time
- Place
- Chicago, Illinois · Chicago O'Hare International · map
- Type
- Incident
- Injuries
- No one was hurt; 324 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Mcdonnell Douglas MD80
- Registration
- not recorded
- Damage
- Not recorded
- Flight
- Flight · scheduled airline rules (Part 121)
- Aircraft 2
- Boeing 767 · all 767s on the register
- Registration
- not recorded
- Damage
- Not recorded
- Flight
- Flight · scheduled airline rules (Part 121)
The NTSB's narrative for the Mcdonnell Douglas MD80 final · quoted from the NTSB record
While on approach to Chicago-O'Hare International Airport, American Airlines flight 879 (AAL 879) was being radar-vectored to the final approach course for runway 28 and American Airlines flight 93 (AAL 93) was on a straight-in approach to runway 27L. Both aircraft were under control of Chicago Terminal Radar Approach Control. Because of an air traffic control oversight, AAL 879 overshot the final approach course for runway 28 and continued northbound, conflicting with AAL 93 on the runway 27L final. According to preliminary Federal Aviation Administration data, lateral separation decreased to 0.35 nautical mile and vertical separation was 0 feet before the conflict was resolved. There were no injuries or damage reported as a result of the incident, which occurred in visual meteorological conditions, with 10 statute miles of visibility and a 5500-foot ceiling.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The NTSB's narrative for the Boeing 767 final · quoted from the NTSB record
While on approach to Chicago-O'Hare International Airport, American Airlines flight 879 (AAL 879) was being radar-vectored to the final approach course for runway 28 and American Airlines flight 93 (AAL 93) was on a straight-in approach to runway 27L. Both aircraft were under control of Chicago Terminal Radar Approach Control. Because of an air traffic control oversight, AAL 879 overshot the final approach course for runway 28 and continued northbound, conflicting with AAL 93 on the runway 27L final. According to preliminary Federal Aviation Administration data, lateral separation decreased to 0.35 nautical mile and vertical separation was 0 feet before the conflict was resolved. There were no injuries or damage reported as a result of the incident, which occurred in visual meteorological conditions, with 10 statute miles of visibility and a 5500-foot ceiling.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record for the Mcdonnell Douglas MD80 from the NTSB's investigation tables, in plain English
What happened, in order
- Near midair/TCAS alert/loss of separation during approach (IFR final approach) defining event
The NTSB's findings
- cause Personnel issues › Task performance › Communication (personnel) › Issuing instructions › ATC personnel
The aircraft
- Landing gear: fixed
The flight
- Departed from: STL St Louis MO
- Destination: ORD Chicago IL
- Flight plan: IFR
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 230° at 12 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 20,000 ft; a few clouds at 5,000 ft
- Temperature: 72°F (22°C), dew point 61°F (16°C)
- Altimeter: 29.82 inHg
- Observation at 4:51 pm from ORD, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Cabi | 3 | |||
| Flight crew | 2 | |||
| Passengers | 105 |
The factual record for the Boeing 767 from the NTSB's investigation tables, in plain English
What happened, in order
- Near midair/TCAS alert/loss of separation during approach (IFR final approach) defining event
The NTSB's findings
- cause Personnel issues › Task performance › Communication (personnel) › Issuing instructions › ATC personnel
The aircraft
- Landing gear: fixed
- Operator: American Airlines INC
The flight
- Departed from: EIDW Dublin
- Destination: ORD Chicago IL
- Flight plan: IFR
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Cabi | 10 | |||
| Flight crew | 2 | |||
| Passengers | 202 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.