CEN18LA158 · Robinson Helicopter R44 UNDESIGNAT
MF Helicopters Robinson Helicopter R44 UNDESIGNAT · Accident: loss of engine power (partial) while maneuvering
Event
- NTSB case
- CEN18LA158
- 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
Robinson Helicopter R44 UNDESIGNAT
- 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
- N444VH
- Operator
- MF Helicopters
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 19 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
- 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
No findings designated as a cause are recorded in the NTSB data yet.
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The flight instructor and pilot receiving instruction were maneuvering to begin practice hovering when the helicopter experienced a lateral vibration. The instructor assumed control of the helicopter and attempted to land; however, the helicopter yawed to the left and both the instructor and pilot applied full right pedal to align the helicopter's nose with its ground track. Shortly thereafter, they heard the low rotor rpm horn and saw the associated warning light illuminate. The helicopter continued to the left, and as they lowered to the ground, the right skid caught on the grass and the helicopter experienced a dynamic rollover, resulting in substantial damage to the main rotor blades and fuselage. Examination of the airframe and engine revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation, and the helicopter had adequate fuel onboard for the flight. Although the weather conditions at the time of the accident were conducive to the formation of carburetor icing at glide and cruise power, the helicopter was equipped with a carburetor heat assist device, which automatically applied or reduced carburetor heat with changes in collective input. The reason for the partial loss of engine power could not be determined based on the available information.
Probable cause
A partial loss of engine power for reasons that could not be determined based on the available information, which resulted in impact with terrain and dynamic rollover during the subsequent attempted landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN18LA158
- Event ID
- 20180507X91846
- Case number
- CEN18LA158
- 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: a23c00c22e2b911872aa55e98f0bbec2e2042ae060abd6d2cf61872dd7e1f9aa; retrieved 2026-09-16T07:04:06.403Z.