What happened
The accident occurred while the aircraft was undergoing a test flight immediately following an annual inspection. According to the pilot's report, the engine experienced a loss of power when the helicopter was at an altitude of approximately 300 feet above ground level and traveling at an airspeed of 50 miles per hour.
In response to the power failure, the pilot initiated an autorotation maneuver. During this emergency descent, he attempted to turn the aircraft to avoid obstacles in the vicinity. Despite these efforts, the helicopter impacted the terrain and subsequently rolled over upon impact.
The investigation
A post-accident examination of the aircraft revealed significant issues within the fuel system. The inspection found that the fuel pump contained corrosion. Additionally, a white powdery substance was discovered in almost every port of the fuel injector. The finger screen associated with the fuel injector was also found to be corroded.
Findings
The mechanical evidence points directly to fuel delivery issues caused by contamination and degradation of components. The presence of corrosion in both the pump and the injector screen, combined with the powdery substance in the injector ports, suggests a failure in the fuel system's integrity that led to the engine power loss.