DEN83LA154 · Bell 47G-3B-1 SOLOY 47G-3B-1 S
Bear Tooth Helicopters Bell 47G-3B-1 SOLOY 47G-3B-1 S · Accident: total loss of engine power (non-mechanical) during an emergency descent
From E. OF TOWNSEND, MT to Townsend, MT
Event
- NTSB case
- DEN83LA154
- 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 47G-3B-1 SOLOY 47G-3B-1 S
- 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
- N1334X
- Operator
- Bear Tooth Helicopters
- Onboard fatalities
- Unknown
- Route
- From E. OF TOWNSEND, MTTo Townsend, MT
- Aircraft age
- Not recorded
- 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
- Emergency descent
- First occurrenceThe 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
- Total loss of engine power (non-mechanical)
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Fuel starvation
- 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
- Pilot in command › Maneuver, excessive
- Pilot in command › Performance data, not identified
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE HELICOPTER MADE A HARD TOUCHDOWN DURING AN AUTOROTATIVE FORCED LANDING AFTER THE ENGINE QUIT. DURING THE LANDING THEMAIN ROTOR SEVERED THE TAIL BOOM. THE PILOT STRETCHED THE AUTOROTATIONAL GLIDE TO REACH A HAY FIELD AND LOST MAIN ROTOR RPM IN THE PROCESS. THE ENGINE DIED OF FUEL STARVATION BECAUSE OF A LOW FUEL STATE AND BECAUSE THE PILOT WAS DESCENDING AT HIGH SPEED WITH NOSE LOW. IN THIS ACFT ACCORDING TO A TEST PILOT WHO SPECIALIZES IN THIS MODEL CAUTION MUST BE USED TO AVOID UNUSUAL PITCH ATTITUDES WITH A LOW FUEL STATE. THE PILOT SAID HE HAD A 30 DEGREE NOSE LOW ATTITUDE. THE FUEL TANKS ARE SLANTED 10 DEGREES AFT TO COMPENSATE FOR A 7 DEGREE NOSE LOW ATTITUDE IN NORMAL HIGH SPEED (80 MPH) CRUISE. THE PILOT SAID THE GAUGES SHOWED ABOUT 10 GALLONS JUST BEFORE THE ENGINE QUIT. HE ALSO STATED THAT HE FELT STARVATION OCCURRED.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record DEN83LA154
- Event ID
- 20001214X43313
- Case number
- DEN83LA154
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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: fd3969d635ac2e9df94b1aa0ec12f6a886cbfc97df4821b0c5caf50b5f33f0ef; retrieved 2026-09-23T21:53:33.031Z.