# NTSB WPR24LA060: Mooney M20J, N2073K, Carlin, NV, December 21, 2023 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: December 21, 2023, 12:10 local (20:10 UTC) - Place: Carlin, NV - Coordinates: 40.58, -116.03 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.5800&lon=-116.0300&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report January 14, 2026 - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FAA, Lycoming Engines - NTSB case key (mKey): 193573 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR24LA060 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/193573/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=193573 - Page: https://openairdocs.org/ntsb/WPR24LA060 ## Probable cause Improper spacing of the magneto’s breaker point contact assemblies, which led to a loss of engine ignition during cruise flight and resulted in a total loss of engine power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Ignition system](https://openairdocs.org/ntsb-findings/01057400): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [All aircraft, 18 cases](https://openairdocs.org/ntsb-findings/01057400/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) ## Analysis About 2 hours into the visual flight rules cross-country flight, the airplane climbed from 11,500 ft to 13,500 ft mean sea level (msl). The pilot configured the airplane’s trim, fuel mixture, and power setting to maintain cruise flight while operating with the fuel selector in the left tank position. About 20 minutes later, the pilot heard what he referred to as a “loud clunk” sound from the engine, followed by strong vibrations and the smell of engine oil. The pilot turned on the fuel boost pump, moved the fuel selector to the right tank position, and made a left turn to the northwest while continuing to troubleshoot the anomaly; he declared an emergency with the air route traffic control center (ARTCC) controller. Moments later, the engine lost all power. The pilot attempted to restart the engine to no avail, selected the nearest suitable landing site, and made an off-airport, gear-up, forced landing in mountainous terrain. Postaccident examination of the engine’s ignition system revealed a malfunction of the single-drive dual magneto. The magneto did not produce spark at any of the ignition leads and was removed for further examination. The magneto distributor housing was removed and neither of the contact assemblies was found to be functioning. The magneto drive was rotated by hand after supplying power and neither the left nor right contact assembly cam follower engaged the main breaker point frame bracket. After manually separating the main breaker point from the retard breaker point, the right magneto produced an audible tone and the green light illuminated; however, the left magneto did not. The magneto was shipped to the manufacturer for bench testing. The bench test revealed that the right magneto produced a spark at each of the four ignition leads. The left magneto did not produce a spark at any of the leads. The magneto distributor housing was removed for further examination, which revealed that the right magneto cam follower was engaging the cam, allowing the contact assembly breaker points to open when the cam lobe lifted the cam follower, contact assembly frame bracket, and breaker point. However, the left magneto cam follower was not engaging the cam. The engine manufacturer’s High Tension Magneto Service Support Manual provided maintenance instructions for the main and retard breaker contact assembly, with instructions to adjust the assembly frame bracket for breaker point clearance. The left magneto main contact assembly was adjusted to increase the breaker point clearance, according to the manual, and the dual magneto was reassembled and bench tested. During the second bench test, the right and left magneto produced electrical impulses to each of the ignition leads in firing order. A review of the airplane’s maintenance logs showed that during the last annual inspection the magneto-to-engine timing was checked. However, a definitive magneto service history could not be determined. Intermittent operation of the magneto wouldresult in, at minimum, the strong vibrations experienced by the pilot, and was the likely origin of the inflight total loss of engine power. ## Factual narrative On December 21, 2023, about 1210 Pacific standard time, a Mooney M20J airplane, N2073K, was substantially damaged when it was involved in an accident near Carlin, Nevada. The pilot and the passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that in preparation for a cross-country flight from Redding Municipal Airport (RDD), Redding, California, he topped off the airplane’s fuel tanks and departed with the intended destination of Glendale Municipal Airport (GEU), Glendale, Arizona. About 2 hours into the flight, the airplane climbed from 11,500 ft to 13,500 ft msl and the pilot configured the airplane’s trim, fuel mixture, and power to maintain cruise flight while operating with the fuel selector in the left tank position. About 20 minutes later, the pilot heard what he referred to as a “loud clunk” sound from the engine, followed by strong vibrations and the smell of engine oil. The pilot turned on the fuel boost pump, moved the fuel selector to the right tank position, and made a left turn to the northwest while continuing to troubleshoot the anomaly; he declared an emergency with the Salt Lake City Center ARTCC controller. Moments later, the engine lost all power. The pilot attempted to restart the engine to no avail, selected the nearest suitable landing site, and made an off-airport, gear-up, forced landing in mountainous terrain. The airplane landed about 9 miles south of Carlin, Nevada, and sustained substantial damage to the outboard section of the right wing. The pilot did not recall the manifold pressure or engine rpm before the loss of power. The single-drive dual magneto was found securely clamped at the mounting pad. The magneto impulse coupling was heard clicking near top dead center during rotation of the crankshaft. However, the magneto-to-engine timing could not be confirmed using a timing synchronizer box, which did not produce an expected audible tone to indicate that either of the magneto contact assemblies were open. The magneto did not produce spark at any of the ignition leads and was removed for further examination. The magneto distributor housing was removed and neither of the contact assemblies was found to be functioning. The contacts did not appear burnt and the plastic cam follower foot was intact and showed no evidence of heat distress. There was no evidence of mechanical malfunction of the internal gears. The wiring within the magneto appeared normal. The magneto cap internal surfaces and wires remained free of oil residue or evidence of arcing. The magneto drive was rotated by hand after supplying power and neither the left nor right contact assembly cam follower engaged the main breaker point frame bracket. After manually separating the main breaker point from the retard breaker point, the right magneto produced an audible tone and the green light illuminated; however, the left magneto did not. Figure. Cam end view ofmagneto. The magneto was shipped to the manufacturer for bench testing. The bench test revealed that the right magneto produced a spark at each of the four ignition leads. The left magneto did not produce a spark at any of the leads. The magneto distributor housing was removed for further examination and revealed that the right magneto cam follower was engaging the cam, allowing the contact assembly breaker points to open when the cam lobe lifted the cam follower, contact assembly frame bracket, and breaker point. However, the left magneto cam follower was not engaging the cam. The engine manufacturer’s High Tension Magneto Service Support Manual (pages 9-15) provided instructions to adjust the assembly frame bracket for breaker point clearance. The instructions stated that the cam should be rotated so the high lobe(s) is (are) under the cam followers of the contact assemblies, that the left main contact should be adjusted to obtain a 0.016 inch (± 0.002) opening, and that the retard contacts should have 0.016 inch (± 0.004) clearance. The contact assembly frame bracket was adjusted to increase the breaker point opening clearance and the magneto drive housing and the distributor housing were reassembled. A second bench test was conducted, and both the left and right magnetos produced electrical impulses to each of the designated ignition leads in firing order (1, 3, 4, 2). The left main contact opening clearance was not measured before or after the bench test. A review of the airplane’s maintenance logs showed that during the last annual inspection, the magneto-to-engine timing was checked. However, a definitive magneto service history could not be determined. ## Aircraft - Registration: N2073K (not matched to a registry record) - Reported make and model: MOONEY M20J - Category: Airplane - Serial number: 24-1344 - Year built: 1982 - Airframe hours: 3894 - Engines: Lycoming IO-360-A3B6D 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 5, 2023 - Departed: RDD, Redding, CA - Destination: GEU, Glendale, AZ - Equipment: ADS-B, Auto-pilot, Electronic flight bag or handheld device, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 66; injuries: minor; private; airplane ratings: single-engine land; medical: basicmed, with waivers/limitations; last flight review July 22, 2022; seat: left; flight hours: 478 total, 320.9 in this make and model, 356.6 as pilot in command, 19.2 in the last 90 days, 4.7 in the last 30 days, 2.9 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 46 °F, dew point 36 °F - Altimeter: 30.16 inHg - Observed at: KEKO, 22 nm away - METAR: KEKO 212056Z AUTO 00000KT 10SM CLR 08/02 A3016 RMK AO2 SLP217 T00830017 58020 PWINO $ ## 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 20231221018669A](https://openairdocs.org/incident/20231221018669A), Dec 21, 2023: Mooney M20J, Elko, NV, Substantial damage. During normal cruise flight from redding CA to suprise AZ engine made a clang and failed causing an off-field landing. Pilot reported smelling oil smell in… ## Docket (9 files) The files NTSB released with the investigation on January 14, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=193573. 137 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 8.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19627430&FileExtension=pdf&FileName=6120_1_Redacted-Rel.pdf - Memorandum for record -PIC (item 2, PDF, 1 page, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19631902&FileExtension=pdf&FileName=Memorandum%20for%20Record%20-PIC-Rel.pdf - Excerpts_magneto service support manual (item 3, PDF, 2 pages, 608 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19664598&FileExtension=pdf&FileName=Excerpts_Magneto%20Manufacturer%20Service%20Support%20Manual-Rel.pdf - Maintenance logbook excerpts (item 4, PDF, 12 pages, 4.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19626748&FileExtension=pdf&FileName=N2073K%20Maintenance%20Logs_Redacted-Rel.pdf - Initial magneto examination video (item 5, MOV, 120 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19665000&FileExtension=MOV&FileName=IMG_0886-Rel.MOV - Investigative photographs (item 6, PDF, 6 pages, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19627050&FileExtension=pdf&FileName=Investigative%20Photographs-Rel.pdf - Examination summary (item 7, PDF, 11 pages, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19665385&FileExtension=pdf&FileName=Exam%20Summary_L-Rel.pdf - Statement of party representatives (item 8, PDF, 14 pages, 136 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19631477&FileExtension=pdf&FileName=NTSB%20party%20form_Lycoming-WPR24LA060_Redacted-Rel.pdf - Release of aircraft wreckage (item 9, PDF, 2 pages, 413 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19631695&FileExtension=pdf&FileName=Release%20of%20Aircraft%20Wreckage_Redacted-Rel.pdf 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.