Individually Owned: 150,657
Corporate Owned: 137,281
Tacoma Narrows Airport
Aircraft Accident/Incident Report
Tacoma, Washington 98335
Sunday, January 12, 2003 15:47 PST
NTSB Narrative Summary Released at Completion of Accident
The pilot reported that while en route, the engine backfired, followed by a total loss of power. The pilot initiated a forced landing, attempting to land at a nearby airport. The aircraft was unable to reach the runway and collided with trees and brush about 200 yards short of the runway. During a post-accident engine examination, the crankshaft was found fractured through the forward side of the number four journal. Metallurgical examination of the fracture surface revealed that the crankshaft failure was the result of fatigue initiating at a subsurface inclusion. Scanning electron microscopic examinations established that the fatigue initiated at a single subsurface site located 0.023 inch below the journal surface. Closer inspection found an approximate 0.002 to 0.003 inch diameter pit at the origin location. The pit was mostly empty but contained remnants of material that was identified by energy dispersive x-ray spectroscopic as mostly aluminum and calcium. The age of the crankshaft could not be determined but appeared to be an older crankshaft that was manufactured prior to the manufacturers transition to vacuum arc remelted steels which have higher fatigue strengths and which almost eliminates the presence of inclusions.
NTSB Probable Cause Narrative
A loss of engine power during cruise flight due to fatigue failure of the crankshaft as a result of an inadequate quality of material during the manufacturing process. Trees were a factor.
Event Information
| Type of Event | Accident |
| Event Date | 1/12/2003 |
| Event Day of the Week | Sunday |
| Time of Event | 1547 |
| Event Time Zone | Pacific Standard Time |
| Event City | Tacoma |
| Event State | WASHINGTON |
| Event Country | -- |
| Zipcode of the event site | 98335 |
| Event Date Year | 2003 |
| Event Date Month | 1 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 471635N |
| Event Location Longitude | 1223437W |
| Event Location Airport | Tacoma Narrows |
| Event Location Nearest Airport ID | TIW |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 0.25 |
| Degrees magnetic from airport | 350 |
| Airport Elevation | 292 |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1553 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | TIW |
| Elevation of weather observation facility | 292 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 5500 |
| Lowest Non-Ceiling Height | 1400 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 10 |
| Dew Point at event time (in degress fahrenheit) | 8 |
| Wind Direction (degrees magnetic) | 350 |
| 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) | 30.02 |
| 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) | 15238 |
| NTSB Notification Source | SEA FAA ROC |
| NTSB Notification Date | Jan 12 2003 12:00AM |
| NTSB Notification Time | 1605 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Mar 30 2004 8:14AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Renton FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N6442Q |
| NTSB Number | SEA03FA025 |
| 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 | Mooney |
| Aircraft Model | M20F |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 670521 |
| Certified Max Gross Weight | 2960 |
| 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 | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Jul 11 2001 12:00AM |
| Airframe hours since last inspection | 96 |
| Airframe Hours | 4586 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Brooks, Lloyd W. |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Olympia |
| Aircraft Owner State | WA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 98502 |
| 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 | No |
| Departure Airport Code | 1S0 |
| Departure City | Puyallup |
| Departure State | WA |
| Departure Country | USA |
| Departure Time | 1530 |
| Departure Time Zone | PST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | OLM |
| Destination City | Olympia |
| Destination State | WA |
| Destination Country | USA |
| Specific Phase of Flight | Landing |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Jan 22 2004 6:17PM |
| User who most recently changed record | STAM |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 17 |
| Runway Length | 5002 |
| Runway Width | 150 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |