# NTSB LAX07LA114: Mooney M20B, N74503, St. George, UT, March 18, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 17, 2007, 18:00 local (Mar 18, 2007, 00:00 UTC) - Place: St. George, UT - Coordinates: 37.040554, -113.60083 - Nearby events: https://openairdocs.org/map.md?lat=37.0406&lon=-113.6008&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report July 25, 2007 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 65452 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX07LA114 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65452/pdf - Page: https://openairdocs.org/ntsb/LAX07LA114 ## Probable cause Oil contamination of the right magneto. Factors were the airplane owner's failure to comply with manufacturer's service bulletins and overhaul porcedures. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, cruise - ignition system,magneto - contamination,other than water (cause) - maintenance,service bulletin/letter - not complied with, owner/pilot mechanic (contributing factor) - maintenance,overhaul - not performed, owner/pilot mechanic (contributing factor) - Forced landing, emergency landing - On ground/water encounter with terrain/water, emergency descent/landing - terrain condition - rough/uneven ## Analysis Ten minutes after takeoff the airplane's engine started running rough, and the airplane collided with terrain during a forced landing into an open area. The pilot leveled the airplane at 6,500 feet for cruise and the engine started running rough and backfiring. The engine would run sporadically rough then smooth out. The pilot executed emergency procedures, switched fuel tanks, and switched on the boost pump, but there was no change in the engine's rough-running condition. He decided to return to the airport, and configured the airplane for best glide. He setup for a 2-mile final to runway 34. The pilot determined that he was not going to make the runway, and force landed the airplane in a clear area by a river bed. An examination of the engine determined that the right magneto contained engine oil. The seal between the engine accessory drive and the magneto was hard, loose fitting, and covered with engine oil. Examination of the engine maintenance logbook revealed that the engine had been manufactured new on February 8, 1979, and installed on the airplane April 13, 1979. A 9-year gap where no maintenance was recorded on the engine occurred between October 1992 (engine total time of 1302.9 hours) and July 2002 (engine total time of 1322.39 hours). A 100-hour inspection was recorded as being completed on July 2, 2002. The most recent 100-hour inspection was performed on June 22, 2006, at 1,439.1 hours total time. There is no record of an engine or magneto overhaul. Lycoming Service Instruction No. 1009AS states that engines that do not accumulate the hourly period of time between overhauls specified (2,000 hours for the O-360-A1D) are recommended to be overhauled in the twelfth year. Teledyne Continental Ignition systems Service Bulletin, SB643B, for all TCM and Bendix magnetos states that the magnetos must be overhauled or replaced at the expiration of 5 years since the date of original manufacture or last overhaul, or 4 years since the date the magneto was placed in service, which ever occurs first with out regard to accumulated operating hours. ## Factual narrative On March 17, 2007, at 1800 mountain daylight time, a Mooney M20B, N74503, experienced a partial loss of engine power after takeoff and forced landed near St. George Municipal Airport, St. George, Utah. The private pilot operated the airplane under the provisions of 14 CFR Part 91. The pilot and single passenger were not injured, and the airplane sustained substantial damage. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight originated at St. George airport at 1745, and was en route to Blackfoot, Idaho. The pilot stated to the National Transportation Safety Board investigator that 10 minutes after takeoff he leveled the airplane at 6,500 feet for cruise; the engine started running rough and backfiring. The engine would run sporadically rough then smooth out. The pilot executed emergency procedures, switched fuel tanks, and switched on the boost pump, but there was no change in the engine's rough running condition. He decided to return to St. George airport, and configured the airplane for best glide. He setup for a 2-mile final to runway 34. The pilot determined that he was not going to make the runway, and force landed the airplane in a clear area by a river bed. The next day a Federal Aviation Administration inspector examined the engine and determined that the right magneto contained engine oil. The seal between the engine accessory drive and the magneto was hard, loose fitting, and covered with engine oil. Examination of the engine maintenance logbook revealed that the engine had been manufactured new on February 8, 1979, and installed on the airplane April 13, 1979. A 9-year gap where no maintenance was recorded on the engine occurred between October 1992 (engine total time of 1302.9 hours) and July 2002 (engine total time of 1322.39 hours). A 100-hour inspection was recorded as being completed on July 2, 2002. The most recent 100-hour inspection was performed on June 22, 2006, at 1,439.1 hours total time. There is no record of an engine or magneto overhaul. Lycoming Service Instruction No. 1009AS states that engines that do not accumulate the hourly period of time between overhauls specified (2,000 hours for the O-360-A1D) are recommended to be overhauled in the twelfth year. Teledyne Continental Ignition Systems Service Bulletin, SB643B, for all TCM and Bendix magnetos states that the magnetos must be overhauled or replaced at the expiration of 5 years since the date of original manufacture or last overhaul, or 4 years since the date the magneto was placed in service, which ever occurs first with out regard to accumulated operating hours. ## Aircraft - Registration: [N74503](https://openairdocs.org/deregistered/N74503-2012-10-19), registration cancelled 2012-10-19, S/N 1814, built 1961 (OpenAirDocs) - Reported make and model: Mooney M20B - Registry model: [Mooney M20B](https://openairdocs.org/model/mooney-m20b) (registry code 5870206) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1814 - Airframe hours: 3958.5 - Engines: Lycoming O-360-A1D 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Steve Laflin - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 1, 2006 - Departed: KSGU, St. George, UT - Destination: KU02, Blackfoot, ID - Airport: KSGU, St. George ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3; flight hours: 462 total, 325 in this make and model, 419 as pilot in command, 68 in the last 90 days, 42 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 14 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 21 °F - Altimeter: 29.90 inHg - Observed at: KSGU, 2 nm away ## 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 20070317003199A](https://openairdocs.org/incident/20070317003199A), Mar 17, 2007: Mooney M20B, Saint George, UT, Substantial damage. (-23) On Saturday March 17, 2007 at approx 1745 MDT, a Mooney M20B, N74503, s/n 1814 departed st. George, UT (sgu) for mesquite, NV (67L), the aircraft made a… 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.