CEN24LA249 · Rotorway 162 F
Rotorway 162 F · Accident en route
From Willow Run Airport (YIP) to an unrecorded destination
Event
- NTSB case
- CEN24LA249
- 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
Rotorway 162 F
- Aircraft type
- Rotorway 162
- 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
- N426DM
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Willow Run Airport (YIP), Belleville, MITo not recorded
- Aircraft age
- About 14 years (built 2010)
- 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
- Unknown or undetermined
- 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
- Not determined › Not determined
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot reported that his preflight inspection of the experimental helicopter revealed no anomalies. About one hour into the flight, the engine and rotor rpm started to drop. When the pilot adjusted the collective and throttle, rotor rpm surged, and engine rpm began to fluctuate. The pilot selected a field and performed a precautionary autorotation. During the touch down, the helicopter’s skids dug into the soft soil and the helicopter spun, which resulted in substantial damage to the main rotor blades, fuselage, and the tail boom. The pilot and the passenger exited the helicopter uninjured. A postaccident examination of the helicopter revealed that fuel remained in the fuel tanks. Examination of the fuel-injected engine did not detect any anomalies that would have precluded normal operation. A roll of blue masking tape was found in the engine cooling shroud, but not in an area that would have interfered with engine operation. Given the lack of anomalies found during the postaccident examination, the reason for the partial loss of engine power could not be determined.
Probable cause
A partial loss of engine power for undetermined reasons.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN24LA249
- Event ID
- 20240708194624
- Case number
- CEN24LA249
- 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: 42718ddf037167b4d37da232d6d75037e60ef6021707efcb84ded2ef5931bb6c; retrieved 2026-09-16T19:00:34.491Z.