Bell 206L-3 N253EV

Summary

On 4 September 1996 at about 20:00 local time, a Bell 206L-3 registered N253EV, operated by U.s. Forest Service, was involved in an accident near Sheridan, Wyoming, United States. One person was on board and one 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 September 1996 at 20:00

Classification

Accident

Location

Sheridan, Wyoming, United States

Coordinates

44.7908, -106.9498

Aircraft

Bell 206L-3

Registration

N253EV

Category

Helicopter

Engines

1

Operator

U.s. Forest Service

Operating rule

Part 91: General Aviation

Purpose of flight

Public Use

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

SEA96TA207

1 person had minor injuries.

the pilot's improper in-flight planning/decision, concerning maneuvers to position the helicopter for aerial application; and inadvertent loss of tail rotor effectiveness, which resulted in loss of directional control and subsequent collision with the terrain. Factors relating to the accident include unfavorable weather conditions (high wind, gusts, turbulence, smoke, and high density altitude); the pilot's lack of recent experience in type of operation, and the lack of suitable terrain for a safe autorotation.

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

Read the full NTSB narrative

The helicopter pilot was attempting to drop water on a forest fire from a sling-loaded bucket. He was flying about 8,200 feet above mean sea level and in close proximity to mountainous terrain. Density altitude was about 11,600 feet, and high winds, gusts, turbulence, and smoke prevailed. As the pilot approached the target area to drop the water, he could not see the target and was advised that he had overflown it. He maneuvered the helicopter in an attempt to be in a position to drop the water after reacquiring the target. There was evidence that the pilot inadvertently encountered a loss of tail rotor effectiveness in unfavorable wind conditions. The helicopter began to spin to the right. The pilot attempted to recover by entering an autorotation; however, before he regained control, the helicopter impacted trees and was substantially damaged. An examination of the wreckage did not reveal evidence of preimpact mechanical deficiencies. The pilot had much experience in helicopters; however, he had no recent mountain flying experience nor any firefighting experience.'

Quoted verbatim from the NTSB record.