No fatalities

Helicopter Engine Failure Leads to Tail Boom Contact During Aerial Application (N7938J)

Salinas, CA, US

On July 6, 2003, a Bell 47 G5 (registration N7938J) was involved in an aviation accident near Salinas, CA. No fatalities were reported. Investigators recorded the probable cause as: The failure of the number 3 piston connecting rod, which led to an in-flight engine shutdown and subsequent loss of control during landing. 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 2026-06-19Data APIEditorial standards

A commercial pilot experienced a violent engine shutdown during an aerial application flight, resulting in a run-on landing that caused the main rotor to strike the tail boom and sever the gearbox.

What happened

The commercial pilot was conducting an aerial application flight when he reported executing several passes with the helicopter. During the downwind leg of the accident approach, the engine shuttered violently before quitting completely. The pilot initiated a run-on landing sequence to manage the loss of power.

During the landing phase, the main rotor blade made contact with the tail boom of the helicopter. This impact resulted in the severing of the tail rotor gearbox. The aircraft sustained significant structural damage during this uncontrolled touchdown.

The investigation

Investigators conducted an external inspection of the helicopter engine and observed that the aft section of the engine case was ruptured. To determine the root cause of the failure, the engine was disassembled for a thorough examination.

Findings

Upon disassembly, the number 3 piston connecting rod was discovered to be broken. This mechanical failure within the engine is identified as the primary cause of the sudden loss of power that precipitated the accident sequence.

Probable cause

The failure of the number 3 piston connecting rod, which led to an in-flight engine shutdown and subsequent loss of control during landing.

Frequently asked questions

What happened in the 6 Jul 2003 Bell 47 G5 accident near Salinas, CA?

A commercial pilot experienced a violent engine shutdown during an aerial application flight, resulting in a run-on landing that caused the main rotor to strike the tail boom and sever the gearbox.

Were there any fatalities in the 6 Jul 2003 Bell 47 G5 accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 6 Jul 2003 involved a Bell 47 G5, registration N7938J, at Salinas, CA.

What was the probable cause of the accident?

The failure of the number 3 piston connecting rod, which led to an in-flight engine shutdown and subsequent loss of control during landing.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20030722X01168. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.