Casualties unknown

1993-08-11: Hiller UH-12E (N100LM) — Pacific Valley Aviation, Inc. — Dixon, CA

Dixon, CA, US

On August 11, 1993, a Hiller UH-12E (registration N100LM) operated by Pacific Valley Aviation, Inc. was involved in an aviation accident near Dixon, CA. Investigators recorded the probable cause as: the failure of the pilot to visually detect and avoid the guy wire. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A helicopter dispensing insecticides struck a guy wire between power line poles, causing pitch link failure. The pilot regained partial control and attempted a landing in a tomato field, where the helicopter overturned.

Accident Overview

An FAA inspector reported that a helicopter involved in agricultural spraying collided with a guy wire while working a field. The helicopter had been dispensing insecticides for about two hours before the accident. After refueling, the pilot departed to finish spraying the remaining corner of the field.

Obstacles in the Field

The field was bordered by a set of power lines on wooden poles, with wires at a height of about 40 feet above ground level. During spray runs, the pilot was flying under these power lines. The last two poles had a one-quarter-inch guy wire strung between them approximately halfway up the poles.

Collision and Damage

On the final pass over the field, the helicopter collided with the guy wire. According to the FAA inspector's examination of the wreckage and witness observations, the wire struck the helicopter between the rotor hub and the swash plate assembly, breaking the pitch change links.

Emergency Landing

After the collision, the pilot was able to regain partial control of the helicopter. The pilot attempted a run-on landing cross furrow in a tomato field located about two miles from the wire strike. During the landing, the helicopter's skids caught on both the plants and the soft furrows, causing the helicopter to tumble to a stop.

Investigation

The FAA inspector based the findings on an inspection of the wreckage and witness observations. No further details about the helicopter, pilot, or injuries were provided in the source.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X13171. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.