Accident Overview
Approximately 10 to 15 minutes after takeoff, a student pilot lost control of the helicopter, resulting in a crash landing into trees. Following the accident, Federal Aviation Administration (FAA) personnel inspected the aircraft and identified a single unusual finding: a failed horizontal stabilizer spar.
Examination of the Stabilizer
Post-crash examination of the horizontal stabilizer revealed that it was originally a Hughes part but had been extensively modified after its manufacture by persons unknown. The stabilizer exhibited several skin cracks, which had been stop-drilled in an attempt to halt crack progression. However, these stop-drilling efforts were unsuccessful. Additionally, all rivets connecting the skin to the spar were nonstandard, further compromising the structural integrity of the component.
Investigation Findings
The failure of the horizontal stabilizer spar, coupled with the prior modification and nonstandard rivets, was the only notable irregularity discovered during the post-accident inspection. No other mechanical or operational anomalies were reported by the FAA personnel.