Incident Description
During a weed control spraying operation, a helicopter experienced a power failure while at an altitude of 45 feet above ground level. The pilot attempted an autorotation, but the helicopter impacted the ground on its left side.
Investigation
The subsequent investigation into the accident revealed that the flexible fuel line to the engine-driven fuel pump was loose at the B-nut connection. The engine assembly had been installed approximately seven hours prior to the accident. No other system failures were identified. It was apparent that the B-nut was not properly secured when the engine was last installed.
Findings
A detailed examination of the fuel system confirmed that the B-nut on the flexible fuel line was not adequately tightened. The engine installation, which took place about seven hours before the accident, did not ensure that this critical connection was secured. With no other mechanical issues found, the investigation concluded that the loose connection was the only anomaly.