Mcdonnell Douglas DC10-10 incident near Chicago, Illinois, May 1, 1995
On May 1, 1995 at about 4:20 pm local time, a Mcdonnell Douglas DC10-10, registered N1811U, 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; 192 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
failure of the safety wire and/or safety wire lug arm on one of the stage one to two disk flange bolts due to an inadequate safetying method.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 1, 1995 · about 4:20 pm local time
- Place
- Chicago, Illinois · O'Hare International
- Type
- Incident
- Injuries
- No one was hurt; 192 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas DC10-10 · all DC10-10s on the register
- Registration
- N1811U · registry record · serial 46610
- 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 flightcrew reported that during the application of takeoff power, when the throttles were in approximately the vertical position, the numbers 1 and 3 engines were indicating approximately 70% N1. The number 2 engine was indicating about 48% N1 and not accelerating. They heard a 'crack' and aborted the takeoff. Examination of the engine revealed that the low pressure turbine (LPT) stage one disk had separated from the LPT rotor at the stage one to two flange joint. Seven intact toroid bolts and sets of associated hardware were recovered. No evidence of fatigue cracking or corrosion (pitting) was noted on any of the bolt pieces recovered from the engine. The shank of one of the toroid bolts exhibited significant damage. The lug arm, used for safetying the bolt, exhibited relatively minor damage. Examination of several of the lug arms revealed 'noticeable wear patterns' and 'crack arrest positions indicative of fatigue cracking.' Statements by UAL maintenance personnel indicate failures of the toroid bolt safeties are occasionally discovered when the engines are disassembled for major overhaul.
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, flight instructor, flight engineer
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 19,011 hours in all; 2,909 in this make and model
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 63,749 hours
- Last inspection: continuous airworthiness programme, July 23, 1994; 1,903 hours since
- Maximum gross weight: 433,000 lb
- Seats: 302
- Landing gear: retractable
- Engine: Cfm CF6-6 (turbojet); 0 hours total
The flight
- Departed from: ORD IL at 5:20 pm
- Destination: IAD Washington DC
- Flight plan: IFR
- Runway 9L, 7,967 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 070° at 15 knots, gusting 24
- Visibility: 15 statute miles
- Sky: scat at 4,000 ft
- Temperature: 52°F (11°C), dew point 37°F (3°C)
- Altimeter: 30.00 inHg
- Observation at 4:15 pm from ORD
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 12 | |||
| Passengers | 180 |
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.