# NTSB SEA08CA202: Mooney M20K, N1157K, Trinity Center, CA, September 12, 2008 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 11, 2008, 17:45 local (Sep 12, 2008, 01:45 UTC) - Place: Trinity Center, CA - Coordinates: 40.982776, -122.693611 - Nearby events: https://openairdocs.org/map.md?lat=40.9828&lon=-122.6936&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Fuel exhaustion](https://openairdocs.org/ntsb-events/192) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report November 10, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 69020 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA08CA202 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/69020/pdf - Page: https://openairdocs.org/ntsb/SEA08CA202 ## Probable cause The complete loss of engine power due to fuel exhaustion as a result of a leak in the fuel system. Contributing to the accident was the rough terrain the airplane encountered during the forced landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fuel system](https://openairdocs.org/ntsb-findings/01022800): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Mooney M20K, 1 case](https://openairdocs.org/ntsb-findings/01022800/cases.md?model=5870220), [All aircraft, 181 cases](https://openairdocs.org/ntsb-findings/01022800/cases.md) - [Landing gear system: main gear strut/axle/truck](https://openairdocs.org/ntsb-findings/01023213): Aircraft › Aircraft systems · Capability exceeded (probable cause); cases with it: [Mooney M20K, 1 case](https://openairdocs.org/ntsb-findings/01023213/cases.md?model=5870220), [All aircraft, 86 cases](https://openairdocs.org/ntsb-findings/01023213/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Mooney M20K, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=5870220), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Unknown: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330); cases with it: [Mooney M20K, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=5870220), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Enroute-cruise: Fuel exhaustion](https://openairdocs.org/ntsb-events/192) (defining event); cases with it: [Mooney M20K, 3 cases](https://openairdocs.org/ntsb-events/192/sequence.md?model=5870220), [All aircraft, 804 cases](https://openairdocs.org/ntsb-events/192/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Mooney M20K, 14 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=5870220), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Mooney M20K, 7 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=5870220), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) - [Landing-landing roll: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Mooney M20K, 3 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=5870220), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis At an undetermined point in time, the bracket that supported the fuel flow transducer for the airplane’s fuel monitoring system failed. This allowed the transducer to vibrate, and ultimately lead to the loosening of the B-nut on the fuel line leading to the transducer. Because the B-nut became almost completely disconnected from the transducer, approximately 40 gallons of fuel was lost overboard during the flight. Because the leak was upstream of the transducer, the fuel management system did not detect or display the loss of fuel, and the engine ultimately lost power due to fuel exhaustion. The pilot executed a forced landing at a non-controlled airport, but intentionally exited the side of the runway surface when it appeared that the airplane could not stop prior to departing the end of the runway and encountering a steep drop-off. After the airplane exited the side of the runway, it entered rough terrain and experienced a collapse of the left main landing gear. The collapse of the gear resulted in substantial damage to both the left wing and the aft fuselage. ## Factual narrative At an undetermined point in time, the bracket that supported the fuel flow transducer for the airplane's fuel monitoring system failed. This allowed the transducer to vibrate, and ultimately lead to the loosening of the B-nut on the fuel line leading to the transducer. Because the B-nut became almost completely disconnected from the transducer, approximately 40 gallons of fuel was lost overboard during the flight. Because the leak was upstream of the transducer, the fuel management system did not detect or display the loss of fuel, and the engine ultimately lost power due to fuel exhaustion. The pilot executed a forced landing at a non-controlled airport, and intentionally exited the side of the runway surface when it appeared that the airplane could not stop prior to departing the end of the runway and encountering a steep drop-off. After the airplane exited the side of the runway, it entered rough terrain and experienced a collapse of the left main landing gear. The collapse of the gear resulted in substantial damage to both the left wing and the aft fuselage. ## Aircraft - Registration: [N1157K](https://openairdocs.org/aircraft/N1157K), registered now, S/N 25-0644 (OpenAirDocs) - Reported make and model: MOONEY AIRCRAFT CORP. M20K - Registry model: [Mooney M20K](https://openairdocs.org/model/mooney-m20k) (registry code 5870220) (OpenAirDocs) - Registry engine: [Continental TSIO-360 series](https://openairdocs.org/engine/continental-tsio-360-series) (registry code 17019, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 25-0644 - Airframe hours: 3005 - Engines: CONT MOTOR TSIO-360 SER 225 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Wings Aloft - Registered owner: Moore Walter C - Airworthiness certificate: Standard, Normal - Last inspection: Annual, November 5, 2007 - Departed: KBUR, Burbank, CA - Destination: KMFR, Medford, OR - Flight plan: IFR - Airport: O86, Trinity Center, runway 32, 3,215 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review July 25, 2008; seat: left; flight hours: 271 total, 27 in this make and model, 271 as pilot in command, 39 in the last 90 days, 20 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 340° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 45 °F - Altimeter: 29.84 inHg ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20080911854729A](https://openairdocs.org/incident/20080911854729A), Sep 11, 2008: Mooney M20K, Weaverville, CA, Substantial damage. At an undetermined point in time, the bracket that supported the fuel flow transducer for the airplane’s fuel monitoring system failed. This allowed the… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.