Casualties unknown

1990-04-12: Bell 47G-2 (N4779U) — Barr, Donald M — Harrisburg, AR

Harrisburg, AR, US

On April 12, 1990, a Bell 47G-2 (registration N4779U) operated by Barr, Donald M was involved in an aviation accident near Harrisburg, AR. Investigators recorded the probable cause as: FAILURE OF THE GENERATOR, AND FAILURE OF THE PILOT TO MAINTAIN ROTOR RPM. 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

While flying low over a peach orchard for frost prevention, the pilot experienced dimmed instrument panel lights and rotor RPM decay, resulting in a run-on landing that damaged the helicopter. Post-accident investigation revealed a generator failure.

Incident Overview

A pilot reported that while operating a helicopter at low altitude over a peach orchard to prevent frost damage, the instrument panel lights dimmed. With restricted instrument visibility, the helicopter "got behind the power curve" and the rotor RPM decayed. Subsequently, a run-on landing was made, resulting in damage to the helicopter.

Investigation Findings

A post-accident investigation revealed that the generator had failed. The pilot's report indicated that the dimming of the instrument panel lights and the subsequent loss of rotor RPM occurred during the low-altitude operation. The precise sequence of events linking the generator failure to the power decay was not specified, but the failure was identified as a key technical issue.

Operational Context

The flight was conducted at low altitude over a peach orchard, a common practice for frost protection. The pilot noted that the restricted visibility of instruments due to the dimmed lights contributed to the difficulty in managing the helicopter's power state, leading to the decay in rotor RPM and the eventual run-on landing. No other factors were cited in the source.

Damage and Outcome

The helicopter sustained damage during the run-on landing. No injuries or fatalities were reported in the source. The investigation concluded with the identification of the generator failure, but no explicit statement of probable cause was provided.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X22988. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.