Incident Overview
After cargo was loaded, the pilot began ground taxiing the helicopter across the ramp. As the aircraft traversed a concrete drainage depression, the left main landing gear separated from the gear tube, causing the helicopter to roll over.
Examination of Landing Gear
Metallurgical examination of the failed landing gear strut revealed pre-existing fatigue cracks on the inside of the gear leg, extending from multiple origins. Additionally, corrosion pitting and remnant tooling marks were found on the surface finish of the lower gear tube inside diameter. The pitted and corroded condition indicated that environmental intrusion of the corrosion preventative material may have occurred during service.
Weight Condition
At the time of the incident, the helicopter was 951 pounds over its certificated maximum gross weight.