Eurocopter AS 350 B2 N165EH

Summary

On 30 October 2011 at about 04:09 local time, a Eurocopter AS 350 B2 registered N165EH, operated by ERA Helicopters LLC, was involved in an accident near Iliamna, Alaska, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

30 October 2011 at 04:09

Classification

Accident

Location

Iliamna, Alaska, United States

Nearest airport

Iliamna (ILI)

Coordinates

59.6769, -155.1033

Aircraft

Eurocopter AS 350 B2

Registration

N165EH

Category

Helicopter

Year built

1989

Engines

1

Operator

ERA Helicopters LLC

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Bethel → Iliamna

Aircraft damage

Destroyed

Weather

VMC

Light

Night/Dark

NTSB number

ANC12FA006

1 person died.

The pilot's loss of control due to sudden medical impairment or incapacitation.

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

Read the full NTSB narrative

The helicopter pilot was under contract to support an aerial seismic survey project in a remote part of western Alaska. The survey crew had completed their survey, and the pilot, who was the only occupant, was relocating the helicopter to the operator's base in south central Alaska; however, poor weather conditions delayed his departure until mid-afternoon on the fourth day. The pilot made two fuel stops while en route, and both fuel vendors noted that the pilot seemed rushed and that he mentioned that he was trying to get to his destination before dark. The operator reported the helicopter overdue when the helicopter failed to arrive and they were unable to make contact with the pilot. Searchers discovered the fragmented wreckage about 7 miles southwest of the destination airport, in an area of marshy, tundra-covered terrain. Dark night visual meteorological conditions prevailed at the destination airport before the accident, and transient snow showers and reduced visibility were reported in the area just after the accident. Examination of the helicopter and engine revealed no preaccident mechanical anomalies that would have precluded normal operation. The debris path and extensive fuselage fragmentation were consistent with the helicopter impacting terrain at high speed. The pilot's autopsy revealed several heart abnormalities, including an enlarged heart, a 90-percent occlusion of the left anterior descending coronary artery, a 99-percent occlusion of the right coronary artery, and an aortic valve that was severely calcified and stenotic. Such findings would have put the pilot at high risk of a sudden cardiac event, including acute myocardial infarction, syncope, or arrhythmia, any of which would have impaired or incapacitated him. Further, the weather and the pilot's rush to reach his destination by nightfall after a 4-day delay may have contributed to the pilot's stress level, increasing the risk that his severe but undiagnosed heart disease would cause an acute medical event during the flight. Given the lack of mechanical deficiencies that would have precluded normal operation of the helicopter, and the pilot's severe coronary artery disease and aortic stenosis, it is likely that the pilot's medical conditions caused sudden impairment or incapacitation, which resulted in the loss of control of the helicopter. Although it is possible that the pilot did not recognize that he was flying the helicopter in a shallow descent into terrain, the overwhelming evidence of heart disease compounded by stress makes it more likely that the pilot was impaired or incapacitated.

Quoted verbatim from the NTSB record.