Boeing 757-222 incident near Salt Lake City, Utah, January 11, 2003
On January 11, 2003 at about 7:45 am local time, a Boeing 757-222, registered N551UA, suffered minor damage in an incident near Salt Lake City, Utah. It was flown under scheduled airline rules (Part 121). No one was hurt; 140 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the arcing wires in the lavatory sensor that resulted in the subsequent fire.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 11, 2003 · about 7:45 am local time
- Place
- Salt Lake City, Utah · map
- Type
- Incident
- Injuries
- No one was hurt; 140 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 757-222 · all 757-222s on the register
- Registration
- N551UA · no longer on the register · serial 25339
- Damage
- Minor damage
- Flight
- Flight · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
The passenger jet was at a cruise altitude of 37,000 feet msl and approximately 95 nautical miles south of Salt Lake City (SLC), when a flight attendant called from the aft cabin and stated there was a fire in the left aft lavatory, and that another flight attendant was fighting the active flames with a Halon extinguisher. The captain declared an emergency, requested priority handling for landing at SLC, and made an uneventful landing. An examination of the airplane revealed the lavatory toilet water level sensor was charred and melted. On further examination, the top left corner of the circuit board in the sensor was melted and consumed. Portions of several wires that had solder attachments to the circuit board at the melted area, including a 115-volt AC input wire and a 28-volt DC ground wire were melted and consumed. The left side of the circuit relay, adjacent to the consumed area of the circuit board, was melted and had melted solder on its exterior. The left hexagon-shaped screw, one of the two screws that mount the relay to the circuit board, was also melted. The manufacturer determined the melting point of the screw was between 2,550 and 2,650 degrees F. The investigation team determined that for these temperatures to occur, one of the wires in the area of the left screw would have had to arc.
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; instrument: airplane
- Flight time: 6,186 hours in all; 1,876 in this make and model; 168 in the last 90 days; 48 in the last 30 days; 4,595 as pilot in command
- Last flight review: June 30, 2002
- Medical certificate: Class 1
- Seat: left
- Injury: no injuries
Co-pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 2,054 hours in all; 243 in this make and model; 171 in the last 90 days; 24 in the last 30 days
- Last flight review: August 31, 2002
- Medical certificate: Class 1
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 41,261 hours
- Last inspection: continuous airworthiness programme, November 17, 2002; 568 hours since
- Maximum gross weight: 240,000 lb
- Seats: 190
- Landing gear: retractable
- Engine 1: Pratt & Whitney PW 2037 (turbofan); 0 hours total
- Engine 2: Pratt & Whitney PW 2037 (turbofan); 0 hours total
- Operator: United Airlines
The flight
- Departed from: SFO San Francisco CA at 5:28 am
- Destination: BOS Boston MA
- Flight plan: IFR
- A second pilot was aboard
Weather at the time
- Light: night, dark
- Visibility: 0.2 statute miles
- Sky: broken clouds at 7,500 ft
- Temperature: 32°F (0°C), dew point 32°F (0°C)
- Altimeter: 30.11 inHg
- Observation at 7:56 am from SLC, 95 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 7 | |||
| Passengers | 133 |
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.