What happened
The ANSV report details several distinct aviation occurrences involving various aircraft types across Italy:
- Piper PA-34-200, registration I-MIMU: During a training flight at Palermo Punta Raisi airport, the nose gear failed to lock in the down position despite visual confirmation from the tower. Upon landing, the nose gear retracted, causing the aircraft to slide on its nose for approximately 100 meters. No injuries were reported.
- Cessna 150, registration I-FFSH: While performing a recreational flight near Santa Maria Nuova di Bertinoro, the pilot experienced engine power loss. The flight continued beyond the planned duration and fuel reserves, leading to an emergency landing in a field. The aircraft sustained extensive damage, but the pilot was unhurt.
- Grob Twin Astir, registration I-IVAS: During a local flight near Monte Marzola, the glider suddenly lost altitude after separating from its tow plane, impacting the ground in a wooded area. The two occupants sustained only minor injuries.
- Yak 50, registration LY-AKU: During an approach at Florence Peretola, the pilot experienced a failure in the left main landing gear. The pilot performed a precautionary landing, favoring the right gear, which resulted in the left wing making contact with the ground. No injuries occurred.
- Socata TB 9, registration I-IAEO: During a flight to the Sabaudia airpark, the aircraft overran the grass runway, impacting trees beyond the landing area. The pilot was uninjured, though the aircraft was heavily damaged.
- Piper PA-28-140, registration I-ICES: During a student pilot's solo training flight at Biella Cerrione, a heavy touchdown during a touch-and-go maneuver triggered a severe bouncing effect (porpoising). This led to the structural failure of the nose gear and the aircraft veering off the runway.
The investigation
The ANSV examined technical components, including the landing gear assemblies of the I-MIMU and LY-AKU aircraft, and reviewed pilot flight logs and maintenance records. For the I-FFSH incident, investigators analyzed flight planning and fuel management. Technical inspections of the I-MIMary nose gear revealed a broken steering flange, while the LY-AKU investigation identified a worn seal in the landing gear piston.
Findings
Key causal factors identified across the incidents include:
- Mechanical failure: A worn seal in the LY-AKU landing gear prevented proper locking, and a broken steering flange contributed to the I-MIMU gear retraction.
- Pilot performance and planning: The I-FFSH incident was caused by inadequate flight planning and failure to monitor fuel reserves. The I-ICES incident resulted from a heavy landing and improper longitudinal control (over-controlling) during a bounce. The I-IAEO overrun was attributed to improper braking technique.
- Operational errors: Previous excessive steering maneuvers on the ground were identified as a likely cause for the I-MIMU landing gear malfunction.