What happened
On May 8, 2012, an Agusta West andland AW119 MKII, registration PP-CGO, was conducting a police operation flight for the State of Goiás Civil Police. The aircraft had departed from Goiânia to investigate a crime scene and was en route to a refueling point in Piranhas, Goiás, when a sudden engine flameout occurred.
During the descent, the aircraft experienced an in-flight loss of control. The impact was severe enough that one of the main rotor blades was separated from the aircraft, landing approximately 150 meters from the primary wreckage. The crash resulted in eight fatalities, including both the pilot, the co-pilot, and six passengers. The aircraft was completely destroyed.
The investigation
CENIPA's investigation focused on the sequence of events leading to the engine failure and the subsequent loss of control. Investigators examined the aircraft's maintenance history, noting that while the aircraft had a valid airworthiness certificate and complied with applicable Service Bulletins, the most recent annual inspection had been completed approximately two months prior.
The investigation also scrutinized the operational environment of the Civil Police Air Unit. Investigators looked into the engine's performance, specifically the interaction between the engine loss of traction, the high torque applied near maximum takeoff weight, and the low momentum of inertia characteristic of the composite main rotor blades. This combination contributed to a rapid drop in rotor RPM and a "cone effect" where the blades bent upward due to centrifugal force and weight, complicating the pilot's ability to maintain control.
Findings
- The primary cause of the accident was an inflight engine flameout.
- The sudden drop in main rotor RPM, exacerbated by the low momentum of inertia of the composite blades, led to an inability to execute a successful autorotation.
- Organizational deficiencies within the Air Unit, including the accumulation of administrative and operational duties by pilots, may have hindered effective oversight of flight safety risks.
- A lack of a structured, regular training program for the crew may have delayed the necessary emergency response and judgment during the engine failure.
- The decision to operate the aircraft after an incomplete prescribed inspection indicated a breakdown in maintenance and operational oversight.