Frontier Flying Service Flight 8606
Piper PA-31-350 · Accident: powerplant system/component malfunction/failure during initial climb
From Aniak Airport (PANI) to Shageluk Airport (PAHX)
Event
- NTSB case
- ANC08LA097
- 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
- Charter & commuter
- 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
Piper PA-31-350
- Aircraft type
- Piper PA-31
- Category
- Airplane
- 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
- N40YR
- Operator
- Frontier Flying Service
- Onboard fatalities
- Unknown
- Route
- From Aniak Airport (PANI), Aniak, AKTo Shageluk Airport (PAHX), Shageluk, AK
- 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 135: Air Taxi & Commuter
- 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
- Initial climb
- 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
- Powerplant system/component malfunction/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
- Aircraft › Aircraft power plant
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The airline-transport-certificated pilot was departing in a twin-engine airplane that was about 130 pounds below its maximum gross weight. About 200 feet above the ground, the pilot reported a loss of engine power in the left engine and smoke was seen coming from the left engine by ground witnesses. The pilot indicated that he feathered the left engine, but that the airplane was descending and he elected to make an emergency landing on a gravel bar about .5 mile from the airport. Following the accident, the operator's maintenance personnel removed the left engine from the airframe and shipped it to an engine repair facility for examination. The airplane's left engine, which was equipped with a turbocharger, was placed on a test stand where it was started and ran, but it would not produce power (measured in manifold pressure) above ambient pressure. The engine's turbocharger was removed and replaced. A second engine run, with the new turbocharger installed, resulted in the engine developing full power. The original turbocharger was disassembled and inspected. The inspection revealed that one of the turbine shaft bearings had failed and that the turbine shaft and blades were damaged. One thrust bearing had fractured, with half of the bearing missing.
Probable cause
A partial loss of engine power during takeoff due to a failure of the left engine's turbocharger as a result of the failure of a turbine shaft bearing. Contributing to the accident was unsuitable terrain for a forced landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC08LA097
- Event ID
- 20080812X01219
- Case number
- ANC08LA097
- 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. 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: 62a88df55514735cdb9830411eaa19c97e93c2075225ea521533b6510dca9560; retrieved 2026-09-15T10:02:44.367Z.