Individually Owned: 150,657
Corporate Owned: 137,281
Flying M Airport
Aircraft Accident/Incident Report
Yamhill, Oregon 97148
Sunday, July 31, 2011 8:30 PDT
NTSB Narrative Summary Released at Completion of Accident
The pilot reported that his approach to, and landing on, the private airstrip in his amateur-built, experimental, conventional gear airplane were normal. During rollout in the calm wind condition, the airplane began an uncommanded right turn. The pilot attempted to correct his loss of directional control by application of rudder and engine power. However, the tail wheel had unlocked and was evidently in a castoring mode. Despite his efforts to straighten the airplane’s path, the airplane veered off the runway and impacted a ditch. During the impact sequence one propeller blade broke, and the left wingtip and a wing rib were broken. The pilot reported that he built and maintained the experimental airplane. He opined that the accident could have been prevented had the angle of the tail wheel assembly been correct. After years of use, the tail wheel spring-to-empennage attachment assembly flattened. The incorrect angle altered the tail wheel’s pivot point. This event, combined with the vibration induced during rollout on the gravel runway, allowed the tail wheel to unlock.
NTSB Probable Cause Narrative
The pilot’s loss of directional control during landing rollout due to an unlocked tail wheel that was caused by a degradation of the tailwheel assembly mounting angle.
Event Information
| Type of Event | Accident |
| Event Date | 7/31/2011 |
| Event Day of the Week | Sunday |
| Time of Event | 830 |
| Event Time Zone | Pacific Daylight Time |
| Event City | Yamhill |
| Event State | OREGON |
| Event Country | -- |
| Zipcode of the event site | 97148 |
| Event Date Year | 2011 |
| Event Date Month | 7 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 452141N |
| Event Location Longitude | 1232111W |
| Event Location Airport | Flying M |
| Event Location Nearest Airport ID | OR05 |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 0 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 448 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Pilot |
| Time of the weather observation | |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | -- |
| Elevation of weather observation facility | -- |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | -- |
| 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) | 18 |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | -- |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.05 |
| 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) | 28914 |
| NTSB Notification Source | NM ROC |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Sep 13 2011 6:14PM |
| User who most recently changed record | coos |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N30456 |
| NTSB Number | WPR11CA358 |
| 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 | MCDONALD LYNN B |
| Aircraft Model | AVID FLYER MARK IV |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1279D |
| Certified Max Gross Weight | 1150 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | -- |
| 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 | Conditional |
| Date of Last Inspection | Aug 22 2010 12:00AM |
| Airframe hours since last inspection | 14 |
| Airframe Hours | 1541 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | C91-A |
| Aircraft Owner Name | MCDONALD LYNN B |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | INDEPENDENCE |
| Aircraft Owner State | OR |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 97351-9562 |
| Operator is an individual? | Yes |
| Operator Name | MCDONALD LYNN B |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | INDEPENDENCE |
| Operator State | OR |
| Operator Country | USA |
| Operator Zip code | 97351-9562 |
| 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 | No |
| Departure Airport Code | S75 |
| Departure City | Independence |
| Departure State | OR |
| Departure Country | USA |
| Departure Time | 800 |
| Departure Time Zone | PDT |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | OR05 |
| Destination City | Yamhill |
| Destination State | OR |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Sep 13 2011 6:14PM |
| User who most recently changed record | coos |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 07 |
| Runway Length | 1200 |
| Runway Width | 40 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |