Mcdonnell Douglas DC-10-10 incident near Las Vegas, Nevada, October 28, 1991
On October 28, 1991 at about 3:05 pm local time, a Mcdonnell Douglas DC-10-10, registered N1820U, suffered minor damage in an incident near Las Vegas, Nevada. It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 179 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
RUPTURE OF A FORWARD PRESSURE BULKHEAD BECAUSE OF CYCLICALLY INDUCED METAL FATIGUE. FACTORS WHICH CONTRIBUTED TO THE INCIDENT WERE: THE OPERATOR'S DECISION NOT TO STRUCTURALLY MODIFY ITS AIRPLANE IN ACCORDANCE WITH THE MANUFACTURER'S BUT RATHER TO RELY ON THE MANUFACTURER'S ALTERNATIVE RECOMMENDATION OF PERFORMING REPETITIVE VISUAL INSPECTION IN THE SUSPECT AREA: AND THE OPERATOR'S FAILURE TO UTILIZE AN INSPECTION PROGRAM ADEQUATE TO VISUALLY DETECT CRACK DEVELOPMENT IN A PREVIOUSLY IDENTIFIED SUSPECT AREA.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 28, 1991 · about 3:05 pm local time
- Place
- Las Vegas, Nevada
- Type
- Incident
- Injuries
- No one was hurt; 179 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas DC-10-10 · all DC-10-10s on the register
- Registration
- N1820U · no longer on the register · serial 46619
- Damage
- Minor damage
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
WHILE CLIMBING THRU 35,000 FT FOR A CRUISE ALTITUDE OF 37,000 FT, THE CREW HEARD A LOUD 'THUMP' & THE ACFT DEPRESSURIZED. AS THE CREW DESCENDED TO 11,000 FT, THE CABIN ALTITUDE CLIMBED TO 30,000 FT. THE FLT DIVERTED TO A NEARBY ARPT & SAFELY LANDED. EXAM OF THE ACFT DISCLOSED THAT REPETITIVE PRESSURIZATION CYCLES CAUSED THE INITIATION OF A FATIGUE CRACK & THE RESULTANT RUPTURE OF A FORWARD PRESSURE BULKHEAD. OVER 14 YRS EARLIER, DOUGLAS ISSUED SERVICE BULLETINS ADVISING OPERATORS THAT LEAKS COULD OCCUR IN THE FWD PRESSURE BULKHEAD AREA BECAUSE OF METAL FATIGUE. DOUGLAS RECOMMENDED THAT SPECIFIC CORRECTIVE ACTION BE TAKEN WHICH INVOLVED INSPECTING THE AREA AT 1,500 HOUR INTERVALS OR MAKING PERMANENT STRUCTURAL AIRFRAME MODIFICATIONS. CONTRARY TO THE MAJORITY OF ACFT OPERATORS, UNITED CHOSE NOT TO STRUCTURALLY MODIFY THIS ACFT. RATHER, IT CHOSE TO PERFORM RECURRING VISUAL INSPECTIONS FOR LEAKS IN THE SUSPECT AREA. THE ACFT'S PRESSURE BULKHEAD RUPTURED 1,367 HRS AFTER IT LAST INSPECTION.
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
- Ratings: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Flight time: 20,000 hours in all
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 50,708 hours
- Last inspection: continuous airworthiness programme, May 18, 1991; 1,367 hours since
- Maximum gross weight: 391,600 lb
- Seats: 287
- Landing gear: retractable
- Engine: Ge CF 6-6 (turbofan); 0 hours total
- Operator: United Airlines
The flight
- Departed from: LAX Los Angeles CA at 2:37 pm
- Destination: DEN Denver CO
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 50 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 14 | |||
| Passengers | 165 |
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 N1820U 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.