British Aerospace BAE 146-200A incident near Chicago, Illinois, December 1, 1999
On December 1, 1999 at about 8:31 pm local time, a British Aerospace BAE 146-200A, registered N606AW, suffered minor damage in an incident near Chicago, Illinois (O'Hare International airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 48 people were on board or involved. The weather was conditions the NTSB did not record.
The NTSB's probable cause their words, unchanged
An undetermined failure in the hydraulic system, which resulted in the airplane's entire braking system becoming temporarily inoperative. A factor associated with the incident was the airport terminal building that was contacted by the airplane.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 1, 1999 · about 8:31 pm local time
- Place
- Chicago, Illinois · O'Hare International
- Type
- Incident
- Injuries
- No one was hurt; 48 people were on board or involved.
- Weather
- conditions the NTSB did not record
- Aircraft
- British Aerospace BAE 146-200A BAE 146-20 · all BAE 146-200As on the register
- Registration
- N606AW · registry record · serial E2033
- Damage
- Minor damage
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
The airplane collided with the terminal building at the O'Hare International Airport. The captain reported he used the procedures in the BAE 146 Pilot Operating Handbook, to transfer fluid between the green and yellow hydraulic systems while the airplane was parked at the gate. He stated he then set the parking brake and checked the hydraulic system pressure. The captain reported they completed the before start, starting engines, and after engine start checklists at which time he signaled to the ramp personnel to remove the chocks. He reported the airplane then started to roll forward. He stated the parking brake was set and all four engines were running. The captain reported he tried the green braking and emergency yellow brake systems, however, the airplane continued to move. He then selected the anti-skid switch to battery and positioned the thrust levers to fuel off. The airplane traveled approximately 50 feet prior to contacting the bottom of the upper level of the terminal and a lower level door at gate B-20C. Postincident inspection of the brakes, hydraulic system, anti-skid system, squat switches, and related electrical system components failed to reveal why the airplane would have moved with the parking brake set. The initiation of the rolling event was not captured on the DFDR. The airplane is designed so that the DFDR does not record when the parking brake is set. On December 10, 1999, the operator issued an Alert Bulletin, prohibiting flight crews from performing hydraulic system fluid transfers. On August 25, 2000, the operator issued another Alert Bulletin, once again allowing flight crews to perform hydraulic system fluid transfers. On September 1, 2000, another Alert Bulletin was issued once again prohibiting flight crews from performing hydraulic system fluid transfers.
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 from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 16,691 hours in all; 4,273 in this make and model; 178 in the last 90 days
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 27,836 hours
- Last inspection: continuous airworthiness programme, November 27, 1999
- Maximum gross weight: 91,200 lb
- Seats: 86
- Landing gear: retractable
- Engine: Lycoming ALF-502R-5 (turbofan); 0 hours total
- Operator: Air Wisconsin
The flight
- Departed from: ORD
- Destination: MLI Moline IL
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 200° at 17 knots, gusting 23
- Visibility: 10 statute miles
- Sky: overcast at 6,000 ft; not recorded
- Temperature: 43°F (6°C), dew point 21°F (-6°C)
- Altimeter: 30.00 inHg
- Observation at 7:56 pm from ORD
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 3 | |||
| Passengers | 45 |
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.
Other NTSB records under N606AW the same tail number, which may have belonged to a different aircraft at the time
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.