DEN82DA037 · Bell 206B III
Public Service Co. of Bell 206B III · Accident: partial loss of engine power (mechanical failure) en route
From Denver, CO to Leadville, CO
Event
- NTSB case
- DEN82DA037
- 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 206B III
- Aircraft type
- Bell 206
- 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
- N580P
- Operator
- Public Service Co. of
- Onboard fatalities
- Unknown
- Route
- From Denver, COTo Leadville, CO
- 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
- En route · cruise
- 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
- Partial loss of engine power (mechanical failure)
- 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
- Bleed air system, valve › Dirty(foggy)
- Bleed air system, valve › Loose
Approximate · Estimated position: the centre of Alma, CO, the place the record names. Not the accident site.
NTSB narrative
THE PILOT REPORTED THAT BEFORE THE ACCIDENT, THE FLIGHT HAD BEEN UNEVENTFUL AND ALL INSTRUMENTS WERE READING NORMAL EXCEPT THE TOT GAUGE. REPORTEDLY, IT WAS INDICATING 750 DEGREES, WHICH WAS ABOUT 100 DEGREES HIGHER THAN NORMAL FOR HIS POWER SETTING OF 70% TORQUE. HE STATED HE WAS FLYING AT 70 KNOTS WHEN THE HELICOPTER STARTED LOOSING RPM. THE PASSENGER STATED THAT THEY WERE ABOUT 200 TO 300 FT ABOVE A RIDGE AS THEY WERE FLYING SOUTHWEST. THE PASSENGER REPORTED THAT AFTER THEY CROSSED THE RIDGE, THE HELICOPTER BEGAN LOSING ALTITUDE FAST. ACCORDING TO THE PILOT, THEY WERE COMING UP ON A RIDGE LINE, WHEN THE RPM BEGAN DROPPING; HOWEVER, HE WAS UNABLE TO DECELERATE ENOUGH TO LAND ON TOP OF THE RIDGE. THE HELICOPTER CAME IN CONTACT WITH THE GROUND ON THE SOUTH-SOUTHWEST SIDE OF THE RIDGE LINE AND CRASHED. EXAMINATION OF THE ENGINE REVEALED THE AIR BLEED VALVE WAS DIRTY AND HAD A HOLE IN THE DIAPHRAGM. IN THIS CONDITION, THE VALVE WOULD CLOSE LATE. THE ELEVATION WAS ABOUT 12,000 FT MSL, WIND GUSTING 30 KNOTS.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record DEN82DA037
- Event ID
- 20020917X01930
- Case number
- DEN82DA037
- 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: 2f7d095af832d4e99c06a16303e53cdf85f26642ad76778a5bbe952b57672b1d; retrieved 2026-09-24T03:37:06.174Z.