Boeing 747-122 accident near Detroit, Michigan, February 12, 1987
On February 12, 1987 at about 4:17 am local time, a Boeing 747-122, registered N4718U, was involved in an accident near Detroit, Michigan (Detroit Metro Wayne CO airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). 3 people were seriously injured and 16 people had minor injuries; 222 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 12, 1987 · about 4:17 am local time
- Place
- Detroit, Michigan · Detroit Metro Wayne CO · map
- Type
- Accident
- Injuries
- 3 people were seriously injured and 16 people had minor injuries; 222 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 747-122 · all 747-122s on the register
- Registration
- N4718U · no longer on the register · serial 19879
- Damage
- Not recorded
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
DRG FLT, UNITED FLT 108 RECD INFO OF A BOMB THREAT. DUE TO A SHORT TIME LIMIT, SPECIFIED IN THE THREAT, THE FLT DIVERTEDTO DETROIT & THE SLIDES WERE USED TO EVACUATE THE ACFT; 8 OF 10 SLIDES DEPLOYED NMLY & WERE USED. THE SLIDE AT DOOR 4R DIDN'T INFLATE & WASN'T USED. THE FLT ATTENDANT (F/A) AT DOOR 5R PERCEIVED THAT THE SLIDE (SLIDE/RAFT) AT THAT LCTN WAS INFLATING SLOWLY. SHE PULLED WHAT SHE THOUGHT WAS THE MANUAL INFLATION HANDLE (MIH) & HEARD A HISSING SOUND. SHE THEN SENT 2 HELPERS (PAX) DWN THE SLIDE. AS THEY EGRESSED, THE SLIDE SEPD FM THE ACFT & FELL TO THE GND; 1 OF THE 2 RECD A SERIOUS BACK INJURY. AS OTR SLIDES WERE USED, 2 OTR PAX RECD SERIOUS LEG INJURIES & 16 PAX RECD MINOR INJURIES. AN INV REVEALED THE F/A AT DOOR 5R INADVERTENTLY PULLED THE RELEASE HANDLE (RH) WHEN SHE ATMTD TO USE THE MIH. BOTH HANDLES WERE MADE OF CANVAS MTRL & WERE ABOUT THE SAME SIZE. THE MIH WAS RED WITH A PIECE OF WHITE MTRL MARKED 'PULL' IN RED LTRS; THE RH WAS WHITE & WAS ALSO MARKED 'PULL' IN RED LTRS. NO REASON WAS FND FOR THE SLIDE AT DOOR 4R NOT TO ENFLATE.
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; instrument: airplane
- Flight time: 14,997 hours in all; 7,043 in this make and model
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 52,055 hours
- Last inspection: approved inspection programme; 278 hours since
- Maximum gross weight: 733,000 lb
- Seats: 445
- Landing gear: retractable
- Engine: P&W JT9D (turbofan); 0 hours total
- Operator: United Airlines
The flight
- Departed from: ORD Chicago IL
- Destination: EWR Newark NJ
- Flight plan: IFR
- Runway 3R, 10,000 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: night, dark
- Wind: from 080° at 9 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 4,500 ft; not recorded at 4,500 ft
- Temperature: 32°F (0°C), dew point 25°F (-4°C)
- Altimeter: 29.00 inHg
- Observation at 3:51 pm from DTW
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 14 | |||
| Passengers | 3 | 16 | 208 |
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 N4718U 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.