What happened
On March 6, 2001, an Agusta A109E helicopter, registration I-CLRM, was performing a short flight near Malagrotta, Rome. The purpose of the flight was to test the functionality of radio equipment following recent repairs.
After a vertical takeoff and reaching a hover approximately one meter above the ground, the pilot attempted to transition into forward flight by adjusting the collective and cyclic controls. However, the aircraft did not respond with the expected performance. The pilot observed a "Master Warning" light and heard a "Rotor Low" audible alarm, indicating insufficient power.
In an attempt to return to the elevated helipad, the pilot applied left pedal to rotate the aircraft. Due to the steep 45-degree slope of the terrain immediately adjacent to the pad, the right landing gear failed to find support, causing the helicopter to overturn. The aircraft sustained heavy damage, including a broken tail rotor blade and structural damage to the dynamic components.
The investigation
The ANSV investigation focused on the engine performance and the pilot's pre-flight procedures. Analysis of the aircraft's permanent memory revealed that while the number 1 engine was operating at power, the number 2 engine was actually in an idle condition at the time of the incident.
The investigation also examined the takeoff weight, which was estimated at 2742 kg. This exceeded the maximum takeoff weight for One Engine Inoperative (OEI) conditions (2530 kg) for a hover out of ground effect, though it was within limits for a hover in ground effect. The investigation confirmed that the aircraft was airworthy and that the mechanical components were properly maintained.
Findings
- The primary cause of the accident was the failure to perform proper pre-takeoff checks, specifically the failure to monitor engine instruments to ensure both engines were producing adequate power.
- The pilot's attention was likely diverted by the presence of two technicians on board and the specific focus on testing the radio equipment, which led to the oversight of the engine'2s idle state.
- The attempt to recover the aircraft using left pedal input increased the power demand, further aggravating the loss of lift.
- The steep terrain at the edge of the helipad contributed to the aircraft overturning once it drifted off the pad.