Individually Owned: 150,657
Corporate Owned: 137,281
Twin Bridges Airport
Aircraft Accident/Incident Report
Twin Bridges, Montana 59749
Thursday, October 18, 2012 14:40 MDT
NTSB Narrative Summary Released at Completion of Accident
The pilot attempted to perform a full-flap soft-field takeoff in the experimental light sport airplane. The pilot had flown about 16 hours in the accident airplane in the 4 months since he purchased it from the airplane builder; however, this was his first attempt at full-flap soft-field takeoff in this airplane. As the airplane left the ground, it rolled abruptly to the right. The right wing tip struck the ground, and the airplane cartwheeled, coming to rest pointing in the opposite direction of intended travel. The right wing and fuselage were substantially damaged.
Postaccident examination revealed that the airplane's flaperons were misrigged and that the resultant difference in flaperon deflection was more extreme in the full flap position. In the full flap position with a full left control deflection input, the right flaperon moved 3 degrees more and the left flaperon 3 degrees less than they would have if properly rigged. The asymmetric nature of the flaperon deflections induced an adverse yaw to the right despite the pilot's corrective control inputs. Examination of the airplane maintenance logbook revealed that the airplane builder performed the most recent annual airworthiness inspection 4 1/2 months before the accident.
NTSB Probable Cause Narrative
The airplane builder’s failure to rig the flight controls correctly, which resulted in a loss of control after takeoff.
Event Information
| Type of Event | Accident |
| Event Date | 10/18/2012 |
| Event Day of the Week | Thursday |
| Time of Event | 1440 |
| Event Time Zone | Mountain Daylight Time |
| Event City | Twin Bridges |
| Event State | MONTANA |
| Event Country | -- |
| Zipcode of the event site | 59749 |
| Event Date Year | 2012 |
| Event Date Month | 10 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 453201N |
| Event Location Longitude | 1121809W |
| Event Location Airport | Twin Bridges |
| Event Location Nearest Airport ID | K7S1 |
| 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 | -- |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1453 Pacific Daylight Time |
| Direction of event from weather observation facility (degrees) | 220 |
| Weather Observation Facility ID | KDLN |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | 20 |
| Time Zone of the weather observation | PDT |
| 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) | 15 |
| Dew Point at event time (in degress fahrenheit) | -6 |
| Wind Direction (degrees magnetic) | 240 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 3 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | -- |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.17 |
| 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 | 1 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 30741 |
| NTSB Notification Source | Pilot |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Nov 20 2012 4:07PM |
| User who most recently changed record | coos |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N960WM |
| NTSB Number | WPR13CA018 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | ALBRIGHT STAN |
| Aircraft Model | KITFOX SUPER SPORT |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | KA09088156 |
| Certified Max Gross Weight | 1320 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | 1 |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 2 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Jun 1 2012 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 71 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | C91-A |
| Aircraft Owner Name | Charles W d'Autremont |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Alder |
| Aircraft Owner State | MT |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 59710 |
| Operator is an individual? | No |
| Operator Name | Charles W d'Autremont |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | Alder |
| Operator State | MT |
| Operator Country | USA |
| Operator Zip code | 59710 |
| Operator Code | -- |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | No |
| 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 | K7S1 |
| Departure City | Twin Bridges |
| Departure State | MT |
| Departure Country | USA |
| Departure Time | 1440 |
| Departure Time Zone | MDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | K7S1 |
| Destination City | Twin Bridges |
| Destination State | MT |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Nov 20 2012 4:07PM |
| User who most recently changed record | coos |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 17 |
| Runway Length | 4300 |
| Runway Width | 60 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |