Boeing 707-323C accident near Denver, Colorado, July 9, 1991
On July 9, 1991 at about 2:36 am local time, a Boeing 707-323C, registered N8404, was substantially damaged in an accident near Denver, Colorado (Stapleton International airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 6 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
IMPROPER OVERHAUL OF THE NOSE GEAR ASSEMBLY BY OTHER MAINTENANCE PERSONNEL.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 9, 1991 · about 2:36 am local time
- Place
- Denver, Colorado · Stapleton International · map
- Type
- Accident
- Injuries
- No one was hurt; 6 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 707-323C · all 707-323Cs on the register
- Registration
- N8404 · no longer on the register · serial 19582LINE663
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
DURING ROTATION ON THE TAKEOFF ROLL, THE NOSE LANDING GEAR CAME OFF THE AIRPLANE AND REMAINED ON THE GROUND. AS THE AIRCRAFT PASSED OVER THE NOSE LANDING GEAR ASSEMBLY, DAMAGE OCCURRED TO THE BELLY OF THE AIRCRAFT. TAKEOFF WAS COMPLETED AND AN EMERGENCY LANDING WAS CONDUCTED WITH THE MAIN LANDING GEAR AND THE STUB OF THE NOSE LANDING GEAR SHOCK STRUT EXTENDED. DISASSEMBLY OF THE SHOCK STRUT INNER CYLINDER REVEALED THE ABSENCE OF SEVERAL PARTS. THE AREA WHERE THESE PARTS ARE LOCATED IS A SEALED AREA THAT WAS NOT COMPROMISED. THIS DISCREPANCY ALLOWED A RETENTION NUT TO BACK OFF WHICH RESULTED IN NOSE GEAR SEPARATION. THE NOSE GEAR ASSEMBLY WAS OVERHAULED ON 9/4/85.
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: 10,271 hours in all; 3,138 in this make and model; 241 in the last 90 days; 78 in the last 30 days
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 322,300 lb
- Seats: 7
- Landing gear: retractable
- Engine: P&W JT3D-3B (turbofan); 0 hours total
- Operator: Southern Air Transport (Sat)
The flight
- Destination: MCI Kansas City MO
- Flight plan: IFR
- Runway 17, 12,000 ft by 200 ft
Weather at the time
- Light: dusk
- Wind: from 190° at 5 knots
- Visibility: 50 statute miles
- Sky: broken clouds at 25,000 ft; scat at 12,000 ft
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 6 |
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 N8404 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.