Accident Overview
On 19 September 2011, an Agusta AB-412 helicopter, registration EC-JRY, operated by FAASA Aviación, S.A., was involved in an accident in the municipality of La Peza, province of Granada, Spain. The aircraft was engaged in a flight at the time of the event.
Investigation
The accident was investigated by the Spanish Civil Aviation Accident and Incident Investigation Commission (CIAIAC). The investigation included recovery and analysis of data from the flight data recorder (FDR) and cockpit voice recorder (CVR), as well as examination of the main transmission gearbox (MGB), engine components, and flight control systems. Inspection of the wreckage and impact site was also conducted.
Findings
The investigation revealed that the accident occurred due to a failure of the main transmission gearbox. The failure was not detected in time by the crew, partly because of the flight conditions at the time and the absence of adequate warning to the flight crew.
The report documented that the aircraft had a valid certificate of airworthiness and that the crew held appropriate licenses. No pre-existing mechanical issues were identified that could have been detected during routine maintenance.
Probable Cause
The CIAIAC determined the probable cause of the accident to be the failure of the main transmission gearbox, which was not identified in a timely manner due to the prevailing flight conditions and a lack of indication or warning to the flight crew.
Safety Recommendations
The CIAIAC issued safety recommendations aimed at improving detection and warning systems for transmission failures in similar helicopter types, and enhancing pilot training for recognizing and responding to such failures.