Individually Owned: 150,657
Corporate Owned: 137,281
Lopez Island Airport
Aircraft Accident/Incident Report
Lopez Island, Washington 98261
Friday, August 24, 2007 17:30 PDT
NTSB Narrative Summary Released at Completion of Accident
While en route to the destination airport, the pilot heard the engine generate a loud "bang," as though something had shattered internally. The engine subsequently experienced a total loss of power. The pilot maneuvered the airplane to a pasture where the airplane collided with a fence during the landing roll. According to the engine logbooks, the last engine annual inspection had been performed about 6 months and 124 hours prior to the accident. The left magneto had been replaced about 3 months and 54 hours prior to the accident. A teardown inspection of the engine disclosed that the left idler gear was damaged with several teeth missing and one tooth wedged between the forward face of the gear and crankcase. A detailed metallurgical examination of the left idler gear revealed that it failed due to fatigue. Fatigue features were observed at two locations, and both had initiated in the radius between a gear tooth flank and the root. The gears that were engaged with the idler gear were intact and mostly undamaged. The fracture surface at one fatigue location on the left idler gear was much more reflective than the other. A reflective surface, indicative of a rubbing motion of one fracture surface against another, indicates a misalignment of the meshing gears to produce the motion. The fracture surface at the other location was duller, indicating that little or no rubbing occurred, consistent with the fracture occurring after the first fracture with the rubbed surface. The second fracture propagated until the material below the gear teeth could no longer support the stresses of operation and the portion of the gear located between the two fatigue fractures departed the left idler gear. The fatigue was probably initiated by abnormal contact between the left idler gear and the other mating gears, with the relatively recent installation of the left magneto gear being suspect as the likely source of the initiating stressors.
NTSB Probable Cause Narrative
A loss of engine power due to the fatigue failure of the left idler gear. Inadequate maintenance installation of the recently installed left magneto was also causal.
Event Information
| Type of Event | Accident |
| Event Date | 8/24/2007 |
| Event Day of the Week | Friday |
| Time of Event | 1730 |
| Event Time Zone | Pacific Daylight Time |
| Event City | Lopez Island |
| Event State | WASHINGTON |
| Event Country | -- |
| Zipcode of the event site | 98261 |
| Event Date Year | 2007 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 482900N |
| Event Location Longitude | 1225615W |
| Event Location Airport | Lopez Island Airport |
| Event Location Nearest Airport ID | S31 |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 209 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1730 Coordinated Universal Time? Same as GMT |
| Direction of event from weather observation facility (degrees) | 5 |
| Weather Observation Facility ID | ORS |
| Elevation of weather observation facility | 31 |
| Distance of event from weather observation facility (units?) | 13 |
| Time Zone of the weather observation | UTC |
| 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) | 30 |
| Air Temperature at event time (in degrees celsius) | 22 |
| Dew Point at event time (in degress fahrenheit) | 12 |
| Wind Direction (degrees magnetic) | 190 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 10 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.85 |
| 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 | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 23188 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Aug 24 2007 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Mar 31 2008 11:52AM |
| User who most recently changed record | NTSB\johb |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | WP-SEA-FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N2939J |
| NTSB Number | LAX07LA268 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | VFR |
| Flight plan Was Activated? | Yes |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Piper |
| Aircraft Model | PA-28-181 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 28-7990576 |
| Certified Max Gross Weight | 2550 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| 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 | Feb 1 2007 12:00AM |
| Airframe hours since last inspection | 124 |
| Airframe Hours | 3326 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Caballeros Aircraft LLC |
| Aircraft Owner Street Address | 1101 163rd avenue se |
| Aircraft Owner City | Snohomish |
| Aircraft Owner State | WA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 98290 |
| Operator is an individual? | Yes |
| Operator Name | Scott H. Anderson |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | -- |
| Operator City | Everett |
| Operator State | WA |
| Operator Country | USA |
| Operator Zip code | 98205 |
| 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 | No |
| Departure Airport Code | PAE |
| Departure City | Everett |
| Departure State | WA |
| Departure Country | USA |
| Departure Time | 1710 |
| Departure Time Zone | PDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | YCD |
| Destination City | Vancouver Islan |
| Destination State | -- |
| Destination Country | CA |
| Specific Phase of Flight | Cruise - normal |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Feb 29 2008 1:11PM |
| User who most recently changed record | COOS |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |