Eurocopter AS 350 BA N230CH

Summary

On 26 September 2011 at about 20:30 local time, a Eurocopter AS 350 BA registered N230CH, operated by Coastal Helicopters Inc, was involved in an accident near Juneau, Alaska, United States. 2 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

26 September 2011 at 20:30

Classification

Accident

Location

Juneau, Alaska, United States

Coordinates

58.7006, -134.8519

Aircraft

Eurocopter AS 350 BA

Registration

N230CH

Category

Helicopter

Engines

1

Operator

Coastal Helicopters Inc

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Juneau → Juneau

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC11LA108

Nobody was injured.

Upslope wind conditions while the helicopter was operating at ground idle, which resulted in the helicopter rollover. Contributing to the accident was the lack of manufacturer data regarding the effect of upslope wind conditions on helicopter ground idle operations.

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

Read the full NTSB narrative

The helicopter pilot was landing at a remote off-airport site, located on an outcrop on the side of a steep slope. The pilot reported that after landing, he initiated the shutdown checklist, including a 2-minute cool down. About 1.5 minutes later, the pilot noticed a strong upslope wind, and the helicopter turned to the right. The pilot attempted to offset the turn with left pedal, but at low rpm, the pedal had no effect. The helicopter lifted off the ground about 3 to 5 feet in a slightly nose-high attitude and simultaneously rolled to the left. The pilot attempted to offset the roll with right cyclic input with no effect. The helicopter continued to lift and roll to the left until the main rotor blades impacted the ground. The helicopter came to rest on its left side. The National Weather Service forecast included surface wind of 35 to 45 knots. Upslope wind conditions developed due to the terrain features and created a situation that the pilot was unable to overcome when the helicopter was at ground idle. Although the pilot checked current and forecast weather before departure, he was unaware that the forecast wind would have such an effect because of a lack of manufacturer data regarding the effect of upslope wind on an idle helicopter.

Quoted verbatim from the NTSB record.