Individually Owned: 150,657
Corporate Owned: 137,281
Helena Regional Airport
Aircraft Accident/Incident Report
Helena, Montana 59442
Saturday, April 20, 2002 12:30 MDT
NTSB Narrative Summary Released at Completion of Accident
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.
NTSB Probable Cause Narrative
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.
Event Information
| Type of Event | Accident |
| Event Date | 4/20/2002 |
| Event Day of the Week | Saturday |
| Time of Event | 1230 |
| Event Time Zone | Mountain Daylight Time |
| Event City | Helena |
| Event State | MONTANA |
| Event Country | -- |
| Zipcode of the event site | 59442 |
| Event Date Year | 2002 |
| Event Date Month | 4 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 463625N |
| Event Location Longitude | 0115858W |
| Event Location Airport | HELENA REGIONAL |
| Event Location Nearest Airport ID | HLN |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 3874 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1253 Mountain Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | KHLN |
| Elevation of weather observation facility | 3874 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | MDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 9 |
| Dew Point at event time (in degress fahrenheit) | -10 |
| Wind Direction (degrees magnetic) | 170 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 4 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.95 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 3 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 12704 |
| NTSB Notification Source | FAA-REGIONAL OPERATIONS |
| NTSB Notification Date | Apr 20 2002 12:00AM |
| NTSB Notification Time | 1245 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Feb 25 2003 9:38AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Helena, Montana |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N959D |
| NTSB Number | SEA02LA074 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Stinson |
| Aircraft Model | 108-2 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 2959 |
| Certified Max Gross Weight | 2959 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 4 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Mar 7 2002 12:00AM |
| Airframe hours since last inspection | 14 |
| Airframe Hours | 1835 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Robert J. Benjamin |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Fort Benton |
| Aircraft Owner State | MT |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 59442 |
| Operator is an individual? | No |
| Operator Name | -- |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | -- |
| Operator State | -- |
| Operator Country | -- |
| Operator Zip code | -- |
| Operator Code | -- |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | HLN |
| Departure City | Helena |
| Departure State | MT |
| Departure Country | USA |
| Departure Time | 1230 |
| Departure Time Zone | MDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | HLN |
| Destination City | Helena |
| Destination State | MT |
| Destination Country | USA |
| Specific Phase of Flight | Takeoff - roll/run |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Sep 23 2002 7:18PM |
| User who most recently changed record | STAM |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | 34 |
| Runway Length | 2980 |
| Runway Width | 75 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |