CEN22LA234 · Robinson Helicopter R44
Robinson Helicopter R44 · Accident: powerplant system/component malfunction/failure while maneuvering
Event
- NTSB case
- CEN22LA234
- 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
- Event fatalities
- Unknown
- 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
Robinson Helicopter R44
- Aircraft type
- Robinson R44
- Category
- Helicopter
- 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
- N94WC
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 23 years (built 1999)
- 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
- Maneuvering · hover
- 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
- Powerplant system/component malfunction/failure
- 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 from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The helicopter pilot was practicing hover takeoffs and landings in a crosswind. The passenger reported that, while hovering before a landing, the helicopter shuddered, and the left skid contacted the ground. The helicopter rolled onto its left side. The helicopter sustained substantial damage to the main rotor blades, fuselage, and tail boom. Examination of the helicopter’s flight control systems and main and tail rotor drive systems did not show any preimpact anomalies that would have precluded normal operation. Examination of the No. 2 cylinder revealed that the exhaust push rod was bent and the exhaust valve was stuck. Borescope inspection of the No. 2 cylinder showed that the exhaust valve had contacted the piston and the intake valve appeared to be recessed in the No. 2 valve seat. The loss of engine power was most likely due to the stuck exhaust valve on the No. 2 cylinder.
Probable cause
The partial loss of engine power in a hover due to a stuck exhaust valve.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN22LA234
- Event ID
- 20220607105203
- Case number
- CEN22LA234
- 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, coordinates, 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: bb2ca003032415976c4d9c2fe9c53402270317ebd48ec849c1c9e66edf3f9fc1; retrieved 2026-09-16T15:17:49.547Z.