What happened
On December 16, 2000, an Alitalia Team McDonnell Douglas MD-82, registration I-DAVT, experienced a left engine flame-out during the initial climb phase after departing Naples Capodichino Airport for Palermo. The crew declared an emergency and returned to the airport, landing safely.
On October 27, 2002, a Cessna 120, registration I-FFLJ, performed an emergency landing in a field at Pian Grande, Castelluccio di Norcia, after experiencing engine power fluctuations at altitudes above 5,000 feet during a recreational flight.
On December 19, 2002, at Torino Aeritalia Airport, an ASK 21 glider, registration I-PAIS, sustained damage to its tail section. The glider had taken off while still attached to a ground handling dolly. Upon being notified of the dolly's presence via radio, the pilot disconnected from the tow plane and initiated an immediate landing, during which the dolly struck the ground and impacted the glider's tail.
The investigation
For the I-DAVT event, investigators examined the engine's P&D valve and reviewed flight data from the DFDR. They discovered a significant external fuel leak originating from the valve.
Regarding the I-FFLJ incident, the investigation focused on the engine's performance and spark plug condition. Technicians found that several spark plugs were heavily fouled and that improper copper gaskets had been used during maintenance.
In the case of the I-PAIS glider, the ANSV examined the pre-flight inspection process and the operator's reporting procedures. The investigation noted that the operator failed to notify the authorities of the damage promptly and had sent the aircraft for repairs before the investigation could take place.
Findings
- The engine failure on the MD-82 was likely caused by maintenance error, specifically the over-tightening of two closing nuts on the P&D valve cover, which damaged the valve body's threaded seat.
- The Cessna 120 engine instability was primarily due to the pilot's failure to use the carburetor heat system at high altitudes, compounded by technical factors including fouled spark plugs and the use of incorrect gaskets.
- The damage to the ASK 21 resulted from an incomplete pre-flight inspection that failed to identify the attached dolly.