What happened
On December 3, 2000, a Robinson R22 Beta helicopter, registration N40630, was involved in an accident at Bolzano Airport. Shortly after departing for a local flight at 10:32 UTC, the pilot notified air traffic control of his intention to perform a simulated autorotation maneuver. The pilot descended to approximately 500 feet to begin the procedure.
At an altitude of about 30 feet, the pilot attempted to terminate the simulation by applying power. However, the engine failed to respond to the control inputs. Unable to arrest the descent, the helicopter impacted the grassy area adjacent to the runway. The occupants, the pilot and one passenger, evacuated the aircraft without injury, though the helicopter sustained substantial damage.
The investigation
The ANSV investigation examined the aircraft's mechanical condition, the pilot's recent flight experience, and the environmental conditions. Post-accident testing of the engine and fuel system showed no mechanical irregularities, and the engine responded normally to power changes during ground testing. The investigation also noted that the aircraft's weight and balance were within limits and the airworthiness documentation was up to date.
Investigators focused on the pilot's recent activity, noting only 13 minutes of flight time on this specific aircraft type within the previous 90 days. Furthermore, while the pilot held a valid FAA license, his most recent flight review had been conducted on a fixed-wing aircraft rather than the R22.
Findings
- The primary cause of the accident was the incorrect execution and setup of the simulated autorotation maneuver.
- The pilot failed to adhere to manufacturer-recommended procedures, specifically regarding the minimum time interval required between takeoff and the commencement of a simulated autorative maneuver.
- The pilot did not utilize carburetor heat, despite meteorological conditions being favorable for ice formation.
- The pilot's limited recent experience on the R22 type may have contributed to an improper maneuver execution or a failure to maintain safe rotor RPM thresholds.
Safety action
- The ANSV recommended that the National Civil Aviation Authority (ENAC) review the adequacy of basic and type-specific training programs.
- The agency emphasized the need for increased awareness regarding the importance of flight reviews and strict adherence to operational procedures and airworthiness limitations.