Bell OH-58C N911PT

Summary

On 8 January 2013 at about 20:25 local time, a Bell OH-58C registered N911PT, operated by Blair Helicopter Service Inc, was involved in an accident near Riverdale, California, United States. One person was on board and one was seriously injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

8 January 2013 at 20:25

Classification

Accident

Location

Riverdale, California, United States

Coordinates

36.3331, -119.8250

Aircraft

Bell OH-58C

Registration

N911PT

Category

Helicopter

Engines

1

Operator

Blair Helicopter Service Inc

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Route

Riverdale → Riverdale

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR13LA087

1 person was seriously injured.

A flight control malfunction while maneuvering for reasons that could not be determined because it was not possible to establish whether observed damage to the flight control assembly was the result of wreckage recovery efforts or a preexisting condition.

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

Read the full NTSB narrative

The pilot was conducting agricultural spray operations when he experienced a flight control system anomaly that was described as a right rolling tendency. The pilot increased altitude in an effort to return to the operator's base for repairs. The helicopter became progressively difficult to control, continuing to roll right and not fully responding to left cyclic control inputs, and the pilot maneuvered to a nearby company loader to land. However, the right rolling tendency continued and the helicopter subsequently collided with terrain. Postaccident examination of the flight control assembly revealed that the gas producer throttle control cable, which is routed adjacent to the connecting linkage push-pull tubes, was entwined with the push-pull tubes. A section of the cable appeared to be pinched between the lower mixing lever unit and the tunnel partition wall. Multiple nylon loop cable clamps, used to secure the throttle cable to the vertical tunnel partition, were broken and separated; however, it was not possible to determine whether the observed damage was the result of the wreckage recovery efforts or a preexisting condition.

Quoted verbatim from the NTSB record.