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ERA22LA039 · Bell 47D1

31 Oct 2021 · Zelienople, PA, United States

Bell 47D1 · Accident

From an unrecorded airport to Butler Farm Show Airport (3G9)

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Event

NTSB case
ERA22LA039
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

Bell 47D1

Aircraft type
Bell 47
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
N132BR
Onboard fatalities
Unknown
Route
From not recordedTo Butler Farm Show Airport (3G9), Butler, PA
Aircraft age
About 70 years (built 1951)
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
Unknown
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

  • Not determined › Not determined

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

The pilot receiving instruction and the flight instructor picked up the helicopter following maintenance and performed a brief instructional flight. The instructor disembarked while the helicopter’s engine continued to run, and the pilot subsequently departed for a solo flight to the home airport. Shortly after departure, the engine “sputtered,” and there was a “drop” in both the engine and main rotor rpms. The pilot performed a 180° turn back toward the departure airport, and when he leveled the helicopter, engine and rotor rpm “returned.” However, soon after, the helicopter lost total engine power. The pilot entered autorotation and maneuvered the helicopter for a “flat” open area but lacked the altitude and rotor rpm to reach it. He landed on sloped terrain, which resulted in the destruction of the main rotor blades and substantial damage to the landing gear and tailboom. Initial examination of the wreckage by Federal Aviation Administration inspectors revealed a fragmented engine accessory case. Examination of the accessory case fragments revealed that the fracture surface features were consistent with overstress due to impact. Other than the fractured accessory case, the initial wreckage examination revealed no evidence of mechanical anomalies. The helicopter’s owner blocked access to the wreckage, and no further examination of the helicopter could be performed. Weather conditions reported in the area at the time of the accident was conducive to the development of serious carburetor icing at a glide power setting. It is possible that carburetor ice may have developed during the time the helicopter was operating on the ground while the instructor disembarked; however, the pilot’s use of carburetor heat was not determined, and other reasons for the loss of engine power could not be ruled out due to the lack of a more extensive examination of the helicopter. Therefore, the reason for the loss of engine power could not be determined based on the available information.

Probable cause

A total loss of engine power for reasons that could not be determined.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ERA22LA039
Event ID
20211101104187
Case number
ERA22LA039
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: 50460c4faadcee844b2e35c24202b4e532ca7e217c8173a7ed1e4eae2e5d58db; retrieved 2026-09-16T14:42:44.582Z.