Piper PA-31-350 N40YR

Summary

On 4 August 2008 at about 23:50 local time, a Piper PA-31-350 registered N40YR, operated by Frontier Flying Service Inc., was involved in an accident near Aniak, Alaska, United States. 8 people were on board and one was seriously injured, 2 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

4 August 2008 at 23:50

Classification

Accident

Location

Aniak, Alaska, United States

Nearest airport

Aniak (PANI)

Coordinates

61.5817, -159.5431

Aircraft

Piper PA-31-350

Registration

N40YR

Category

Airplane

Engines

2

Operator

Frontier Flying Service Inc.

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Aniak → Shageluk

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC08LA097

1 person was seriously injured.

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.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full 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.

Quoted verbatim from the NTSB record.