Bell 206B N90326

Summary

On 17 June 2022 at about 13:15 local time, a Bell 206B registered N90326, operated by Alpine Helicopter Service Inc, was involved in an accident near Stockton, California, United States. One person was 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

17 June 2022 at 13:15

Classification

Accident

Location

Stockton, California, United States

Coordinates

37.9089, -121.3739

Aircraft

Bell 206B

Registration

N90326

Category

Helicopter

Year built

1975

Engines

1

Operator

Alpine Helicopter Service Inc

Operating rule

Part 91: General Aviation

Purpose of flight

Positioning

Phase of flight

Not recorded

Route

Lodi → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR22LA221

Nobody was injured.

Tail rotor blade impact with an unidentified object, which resulted in the loss of control and subsequent rollover of the helicopter.

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

Read the full NTSB narrative

The pilot had departed his home base to relocate the helicopter for an upcoming aerial application job when he felt a vibration and heard a bang, followed immediately by an uncommanded right yaw. While performing a precautionary landing to an orchard, the helicopter entered an uncommanded, continuous right rotation about the vertical axis. The pilot rolled off the throttle and increased collective to cushion the landing, but the helicopter continued the right rotation as it touched down, which resulted in the helicopter rolling over onto its left side. The helicopter sustained substantial damage to the fuselage, transmission, main rotor, and tail rotor assemblies. Fragments of one tail rotor blade was recovered about 2,000 ft from the main wreckage. The pilot stated that he was unsure if a bird had struck the tail rotor during flight. Postaccident examination of the tail rotor assembly revealed both blades were damaged, and one blade fractured and separated from the hub. The tail rotor blades were shipped to the National Transportation Safety Board (NTSB) materials laboratory, and subsequently to the manufacturer’s laboratory for further examination. The combined examinations revealed translaminar overstress fractures of both tail rotor blades, with one blade exhibiting a leading-edge high-energy impact. Both blades exhibited an unidentified foreign material transfer onto their leading edges. A small amount of nitrile rubber was found lodged into the end of one blade; however, its origin was undetermined.

Quoted verbatim from the NTSB record.