Robinson R44 II N4186Y

Summary

On 7 September 2009 at about 01:35 local time, a Robinson R44 II registered N4186Y, operated by Alpine Air Alaska Inc, was involved in an accident near Central, Alaska, United States. 3 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

7 September 2009 at 01:35

Classification

Accident

Location

Central, Alaska, United States

Coordinates

65.5739, -144.7808

Aircraft

Robinson R44 II

Registration

N4186Y

Category

Helicopter

Engines

1

Operator

Alpine Air Alaska Inc

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Fairbanks → Central

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC09LA098

Nobody was injured.

The pilot’s failure to maintain control of the helicopter after an in-flight encounter with a downdraft while landing. Contributing to the accident was the pilot’s inadequate evaluation of wind conditions.

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

Read the full NTSB narrative

The airline transport helicopter pilot reported that he was on a Title 14, CFR Part 135 passenger flight and was approaching a mountain ridge to drop off two technicians at a radio repeater site. Before beginning his approach, the pilot circled the site to determine the wind conditions, and then began his approach into a 10 knot wind. During the approach to the 5,657 foot level site, the pilot said he encountered a downdraft as the helicopter approached the site, and the helicopter descended below his anticipated approach path. He initiated a go-around, but the helicopter continued to descend, and landed hard, about 150 feet short and down slope of his intended touchdown point. During touchdown, the toes of the helicopter’s skids broke, and the helicopter rocked forward and aft, sustaining substantial damage to the right side of the tail boom. The pilot reported wind conditions on the ground as variable, gusting between 10 and 20 knots. In the pilot’s written statement to the NTSB, he reported that there were no preaccident mechanical problems with the helicopter.

Quoted verbatim from the NTSB record.