Piper PA-30 accident near Butte, Montana, March 29, 1991
On March 29, 1991, a Piper PA-30, registered N7133Y, was substantially damaged in an accident near Butte, Montana (Bert Mooney airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed and 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
INADEQUATE INFLIGHT DECISIONS, FUEL STARVATION, AND FAILURE TO PERFORM ALTERNATIVE IFR APPROACH PROCEDURES. FACTORS INCLUDE OPERATION WITH KNOWN DEFICIENCIES IN EQUIPMENT, DISORIENTATION, AND LACK OF FAMILIARITY WITH THE GEOGRAPHIC AREA.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 29, 1991
- Place
- Butte, Montana · Bert Mooney · map
- Type
- Accident
- Injuries
- 1 person was killed and 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-30 · all PA-30s on the register
- Registration
- N7133Y · registry record · serial 30-155
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT OF THE PIPER PA-30 DECLARED AN EMERGENCY AFTER FAILURE OF BOTH ENGINES, AFTER THREE ILS APPROACH ATTEMPTS. DURING THE LANDING AFTER HIS EMERGENCY DESCENT, THE RIGHT WING-TIP STRUCK THE SNOW-COVERED SURFACE AND THE AIRCRAFT SLID TO A STOP SIDEWAYS. A TOTAL OF 10.75 GALLONS OF FUEL REMAINED IN THE AIRCRAFT. THE AIRCRAFT HAD BEEN ALOFT APPROXIMATELY 5.25 HOURS. WEATHER AT THE DESTINATION AIRPORT WAS VFR.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 555 hours in all; 68 in this make and model; 43 in the last 90 days; 16 in the last 30 days; 314 as pilot in command
- 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: 3,600 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming IO-320-B1A (piston); 0 hours total
The flight
- Departed from: BIS Bismark ND at 7:48 pm
- Flight plan: IFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 300° at 15 knots
- Visibility: 5 statute miles
- Sky: broken clouds at 4,500 ft; not recorded
- Temperature: 0°F (-18°C), dew point 0°F (-18°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.