What happened
On March 13, 2009, a Bell 222, registration N222LL, was performing an enroute cruise at approximately 1,500 feet above ground level. During the flight, the pilot experienced a physical bump in the controls accompanied by an audible bang. The pilot initially suspected a bird strike; however, a witness on the ground observed several pieces falling from the helicopter and landing in nearby yards.
The pilot subsequently returned to the departure airport, located 45 miles away, and performed an uneventary landing. The pilot and passenger were not injured.
The investigation
Post-flight inspections revealed that the lower portion of the left engine cowling had separated from the aircraft. The investigation found that the detached cowling pieces had struck both main rotor blades and both tail rotor blades. This impact resulted in substantial damage to the left engine cowling, both tail rotor blades, the tail rotor yoke, and the tail rotor gearbox.
While the pilot reported conducting a preflight inspection prior to departure, an FAA inspector examined the aircraft and the separated cowling pieces. The inspector found no evidence of bird remains and determined there was no damage to the cowling latches that would have prevented them from functioning correctly before the incident.