Stinson 108-2 accident near Helena, Montana, April 20, 2002
On April 20, 2002 at about 6:30 pm local time, a Stinson 108-2, registered N959D, was substantially damaged in an accident near Helena, Montana (Helena Regional airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Fracture of the left main wheel assembly during the takeoff roll. Factors include the use of a wheel assembly not approved for the accident airplane, and the use of an oversized tire.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 20, 2002 · about 6:30 pm local time
- Place
- Helena, Montana · Helena Regional · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Stinson 108-2 · all 108-2s on the register
- Registration
- N959D · registry record · serial 2959
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that shortly after applying power for takeoff, the airplane started to track left of runway centerline. During his attempts to correct the situation, the airplane's right main wheel assembly and right landing gear strut collapsed. Post-accident examination of the wheel assembly and tire installed on the accident airplane revealed that the outboard wheel subassembly fractured in multiple locations along the bead seat ring. Multiple fractures were observed in the inboard wheel subassembly, and the brake disc had partially separated from the wheel. The Type Certificate Data Sheet for the airplane lists multiple approved wheel-brake assemblies for the aircraft. The wheel assembly found on the airplane is not listed as one of the approved installations, and the wheel assembly was not approved for use with tires larger than size 7.00-6. The accident airplane was equipped with 8.00-6 size tires. The airplane's last inspection, an annual inspection, was performed on March 7, 2002.
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: single-engine land; instrument: airplane
- Flight time: 561 hours in all; 14 in this make and model; 14 in the last 90 days; 14 in the last 30 days; 561 as pilot in command
- Last flight review: March 13, 2002
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 1,835 hours
- Last inspection: annual inspection, March 7, 2002; 14 hours since
- Maximum gross weight: 2,959 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-360 (piston); 0 hours total
The flight
- Departed from: HLN Helena MT at 6:30 pm
- Destination: HLN Helena MT
- Flight plan: none
- Runway 34, 2,980 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 170° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 48°F (9°C), dew point 14°F (-10°C)
- Altimeter: 29.95 inHg
- Observation at 6:53 pm from KHLN
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 |
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.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number SEA02LA074.