What happened
On July 27, 2014, an AS350 B3 helicopter, registration I-LUPU, was conducting a routine "weekly startup" flight at Lago del Salto, Italy. The flight, intended to verify engine parameters following a period of inactivity, involved a short local flight following engine start-up. While flying at a very low altitude near a nautical center, the aircraft struck the tensioned steel cables of a wakeboard cable system.
Following the impact, the pilot attempted to divert to a nearby clearing at Gola del Varco to perform a precautionary landing. However, during the approach, the aircraft entered an uncontrolled rotation and struck the ground with significant force. The crash resulted in two fatalities (the pilot and a passenger) and one injury (the flight technician).
The investigation
The ANSV investigation focused on the mechanical integrity of the aircraft and the flight dynamics following the cable strike. Technical examinations of the engine and the VEMD (Vehicle and Engine Multifenn Multifunction Display) confirmed that the engine was functioning normally prior to the impact and that any fire damage occurred post-crash.
Specialized analysis of the tail rotor drive shaft by the Italian Air Force Experimental Flight Center revealed that the shaft had failed due to a bending overload caused by the impact with the tensioned cables. Eyewitness accounts corroborated that the helicopter flew at an extremely low altitude—estimated at only a few meters above the water—before striking the cables and subsequently losing control during the landing attempt.
Findings
- The primary cause of the accident was the loss of control of the aircraft due to the failure of the tail rotor drive shaft caused by contact with the wakeboard cables.
- The pilot violated VFR (Visual Flight Rules) minimum altitude requirements by flying at an extremely low altitude near the wakeboard facility without operational necessity.
- The pilot failed to properly assess the severity of the damage following the cable strike, attempting a landing maneuver without first verifying the controllability of the tail rotor.
- There were significant deficiencies in Crew Resource Management (CRM), characterized by a lack of pre-flight briefing and poor communication between the pilot and the technician.
- The presence of an unauthorized passenger on board was in violation of the operator's internal procedures.