CEN09LA284 · Cessna 421B
O'Hara Flying Service II LP Cessna 421B · Accident: loss of engine power (partial) during initial climb
From Alpine, TX to Rick Husband Amarillo International Airport (AMA)
Narrative check · The NTSB narrative appears to contradict this record's location. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- CEN09LA284
- 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
- Accident
- 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 421B
- Aircraft type
- Cessna 421
- 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
- N60HG
- Operator
- O'Hara Flying Service II LP
- Onboard fatalities
- Unknown
- Route
- From Alpine, TXTo Rick Husband Amarillo International Airport (AMA), Amarillo, TX
- Aircraft age
- Not recorded
- 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
- Initial climb
- 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 (partial)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft power plant
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
Shortly after departure, when the airplane was about 400 feet in the air, the right engine stopped producing power. The pilot conducted a forced landing in a nearby field. An on-site inspection revealed that the airplane fuel tanks contained plenty of fuel. A post accident examination of the engines was conducted. An engine monitor was downloaded; a sudden decrease in cylinder head (CHT) and exhaust gas (EGT) temperature readings were observed for the right engine. A visual inspection of the engine revealed that the idler gear support pin, located on the rear of the engine, had backed out. The idler pin's retaining hardware (two nuts and lock-washers) were missing. The idler pin's movement allowed the idler gear to drop and become disconnected from the magnetos drive gear, resulting in a loss of engine ignition. Additionally, due to the mis-located idler gear, the accessory drive gears on the cam and crankshafts were either ground down or broken. Disassembly of the engine, found numerous metal pieces in the engine's oil sump.
Probable cause
The loss of engine power due to disengagement of the magneto idler gear support pin.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN09LA284
- Event ID
- 20090511X84350
- Case number
- CEN09LA284
- 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: fe6991ec82dbb29f0cbfe2efa21501b68f939e949e33610914a73626a2b44930; retrieved 2026-09-15T11:02:24.473Z.