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ERA20LA216 · Bell 47G 3B1

14 Jun 2020 · Atoka, TN, United States

A&F Aviation Services Bell 47G 3B1 · Accident: loss of engine power (total) while maneuvering

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Event

NTSB case
ERA20LA216
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

Bell 47G 3B1

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
N473TT
Onboard fatalities
Unknown
Route
From not recordedTo not recorded
Aircraft age
About 52 years (built 1968)
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
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 (total)
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 as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

The pilot had conducted eight brief (7- to 8-minute) nonrevenue passenger flights uneventfully on the day of the accident. The helicopter was fueled before the eighth flight. During the ninth flight, the helicopter’s engine lost total power when the helicopter was about 1.5 miles north of the heliport and was descending through an altitude of 900 ft mean sea level. The pilot executed an autorotation and landed in a field. On touchdown, the main rotor blade struck the tailboom.

Postaccident examination of the airframe and engine revealed no evidence of any preimpact malfunctions except for the fuel line to the carburetor, which had collapsed. A borsescope inspection revealed that light could not be observed through the fuel line. The borescope was then pushed through the fuel line, and no contaminates were found. A subsequent metallurgical examination of the fuel line revealed no blockages; no damage to the interior of the hose; and no evidence of kinks, creases, or material creep. The blocked fuel line likely resulted in the loss of engine power; however, the reason for the blockage could not be determined.

Probable cause

A total loss of engine power due to a blocked fuel line; the reason for the blockage could not be determined based on the available evidence.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ERA20LA216
Event ID
20200615X01458
Case number
ERA20LA216
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: local date, investigation status, cause areas. Values present in the bulk record are kept.
  • The date is the local date; the NTSB stores the UTC date 2020-06-15.
  • API snapshot SHA-256: 062ef06d26e3a0cb3c338f184b381e4e643773a6a60371fddec13e5bc1a70f89; retrieved 2026-09-16T11:51:12.264Z.