WPR24LA159 · Nanchang China CJ-6A
Nanchang China CJ-6A · Accident: loss of engine power (partial) en route
From Phoenix Deer Valley Airport (KDVT) to an unrecorded destination
Event
- NTSB case
- WPR24LA159
- 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
- 0
- 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
Nanchang China CJ-6A
- Aircraft type
- Nanchang China CJ-6
- 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
- N4182C
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Phoenix Deer Valley Airport (KDVT), Deer Valley, AZTo not recorded
- Aircraft age
- About 57 years (built 1967)
- 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 (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
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that he was conducting a formation flight with another airplane when the engine began making “clicking” and “banging” sounds, surging in speed, and losing power. The pilot attempted to troubleshoot the partial loss of engine power but was unsuccessful. Unable to maintain altitude, the pilot performed a forced landing at a closed gliderport but was unable to stop the airplane on the runway. During the landing sequence, the airplane subsequently crossed over a road and struck an unoccupied camper and the ground, sustaining substantial damage to the left wing and engine mount. A postaccident examination of the engine revealed that the crankshaft front section was separated (fractured through) at the master connecting rod journal and crankpin areas. The crankshaft fracture surfaces showed features consistent with a fatigue fracture initiating from an area of substantial scoring damage on the journal radius. The master rod main bushing (bearing) was found rotated within its pressed fitting about 90° from its original position and also showed substantial scoring damage and wear. The two main bushing set screws (which held the master rod main bearing in place) were not present and were not identified during the examination. Based on the mechanical damage and deformation observed on the main bushing set screw holes, the forward side of the main bushing edge (positioned nearest to the journal radius), and the connecting rod ends near the set screw areas, the set screws likely loosened and backed out, then remained in the small cavity between the connecting rod ends and the master rod until they sustained enough mechanical deformation to exit the area. The main bushing set screw holes showed three installation chiseled strike marks each, indicating that the main bushing was likely previously replaced two times on the master rod. It is likely that the set screws were not properly installed with the appropriate strike marks, which allowed them to loosen.
Probable cause
The partial loss of engine power during cruise flight due to the improper installation of the master connecting rod main bushing set screws, which backed off and allowed the main bushing to shift, resulting in scoring damage on the crankshaft that led to the initiation of a fatigue crack and separation of the forward crankshaft.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR24LA159
- Event ID
- 20240522194307
- Case number
- WPR24LA159
- 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, cause areas. 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: 38668189d749b82c0d4ed1afa484c1a245542cf074b6266582e4204f715ddd39; retrieved 2026-09-16T18:47:47.531Z.