WPR16IA044 · Cessna Aircraft Co LC41-550FG UNDESIGNAT
Cessna Aircraft Co LC41-550FG UNDESIGNAT · Incident: loss of engine power (total) en route
From KMYG · San Diego, CA to Long Beach International Airport (KLGB)
Narrative check · The NTSB narrative appears to contradict this record's departure or destination. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- WPR16IA044
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Incident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Cessna Aircraft Co LC41-550FG UNDESIGNAT
- Aircraft type
- Cessna 41
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N932AC
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route Possible conflict
- From KMYG · San Diego, CATo Long Beach International Airport (KLGB), Long Beach, CA
- Aircraft age
- About 7 years (built 2008)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of engine power (total)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Aircraft › Aircraft power plant
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The commercial pilot reported that the engine started "missing" [running rough] just after departure but he corrected the condition by leaning the mixture. While in cruise the engine started "missing" again but smoothed out after he turned towards a nearby airport, at which point the pilot decided to continue to his destination. When approximately 4 miles away from his destination the engine started to run rough, then quit. The pilot made a forced landing in to an open area. The pilot stated that he did not perform a magneto check at any time after the engine began running rough.
Examination of the engine magnetos revealed that the left magneto gear washer and nylon washer had been installed in reverse order resulting in rapid bushing wear and excessive radial play of the distributor drive gear. This wear led to a migration of the internal timing in the left magneto that could have led to misfires or kickbacks during start that caused shock to the gear train and damaged one or more distributor gear teeth in the right magneto. Damage to one or more gear teeth led to a cascade of gear tooth fractures as the right magneto continued to operate. Eventually the right magneto drive gear decoupled from the engine resulting in cylinder 3 or 6 receiving a spark each time the points were opened during cam rotation, causing random ignition of the fuel-air mixture in those cylinders.
The pilot's failure to follow the Pilot's Operating Handbook guidance to check the operation of the individual left and right magnetos once the engine began running rough likely missed the opportunity to regain engine power utilizing the functional left magneto.
Probable cause
Improper maintenance performed on the left magneto which led to a loss of engine power. Contributing to the incident was the pilot's failure to check the magnetos in flight in compliance with manufacturers guidance regarding rough running engine. The pilot's decision to continue the flight after experiencing the rough running engine contributed to the necessity for a forced landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR16IA044
- Event ID
- 20151229X32052
- Case number
- WPR16IA044
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 910685161c0f42895abc8ae9f2a191c3324942864cb779bbf975bfdcccdd3d6f; retrieved 2026-09-16T03:03:39.017Z.