Piper PA-31-350 accident near Denver, Colorado, November 29, 1991
On November 29, 1991 at about 10:05 am local time, a Piper PA-31-350, registered N354AC, was substantially damaged in an accident near Denver, Colorado (Stapleton International airport). It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). No one was hurt; 2 people were on board or involved. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
A FALSE UNSAFE LANDING GEAR INDICATION DUE TO A FROZEN DOWN LOCK SWITCH. FACTORS WERE: ICING CONDITIONS AND LOW CEILINGS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 29, 1991 · about 10:05 am local time
- Place
- Denver, Colorado · Stapleton International
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Piper PA-31-350 · all PA-31-350s on the register
- Registration
- N354AC · no longer on the register · serial 31-7752049
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
DURING THE APPROACH, THE PILOT COULD NOT OBTAIN A GEAR DOWN AND LOCKED INDICATION ON THE LEFT MAIN LANDING GEAR. HE ELECTED TO LAND GEAR UP WHICH CAUSED SUBSTANTIAL DAMAGE TO THE BOTTOM OF THE FUSELAGE. POSTACCIDENT TESTS REVEALED THAT THE LEFT MAIN LANDING GEAR DOWN LOCK SWITCH HAD FROZEN FROM AN ACCUMULATION OF ICE. WEATHER CONDITIONS AT THE TIME INCLUDED ICING, LOW CEILINGS AND LOW VISIBILITY. PRIOR TO THE ACCIDENT, THE PILOT REPORTED ACCUMULATIONS OF MODERATE ICE. FOLLOWING THE ACCIDENT, ICE ACCUMULATION OF UP TO 3 INCHES WAS FOUND ON THE AIRCRAFT.
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
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 3,179 hours in all; 490 in this make and model; 282 in the last 90 days; 94 in the last 30 days; 2,876 as pilot in command; 330 on instruments
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 7,000 lb
- Seats: 2
- Landing gear: retractable
- Engine: Lycoming LTSID-540-J2B (piston); 0 hours total
- Operator: Alpine Air, INC.
The flight
- Departed from: SLC Salt Lake City UT at 7:30 am
- Flight plan: IFR
- Runway 26, 10,004 ft by 150 ft
Weather at the time
- Light: night, dark
- Visibility: 1 statute miles
- Sky: overcast at 400 ft; not recorded
- Temperature: 28°F (-2°C), dew point 28°F (-2°C)
- Altimeter: 29.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 |
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.