What happened
On November 2, 2014, a SIAI-Marchetti S.208A, registration I-SJAU, was conducting a maintenance check flight departing from Reggio Calabria (LICR). Approximately 20 minutes into the flight, the pilot noticed irregular engine operation, characterized by white smoke and oil pressure dropping to zero. Shortly thereafter, the engine ceased functioning entirely.
Unable to return to the departure aerodrome, the pilot attempted to reach Reggio Calabria, but the engine failed completely at an altitude of approximately 1,000 feet. The pilot delegated the emergency landing maneuver to the passenger—an experienced flight instructor—who performed a forced landing on a beach near Punta Pellaro. During the landing, the aircraft's left wingtip struck a tree before the plane came to a halt on the sand. Both occupants escaped the two individuals on board without injuries, though the aircraft sustained significant damage to the fuselage, landing gear, and left wing.
The investigation
The ANSV examined the engine's maintenance history and conducted a technical teardown of the Lycoming O-540-E4A5 engine. The investigation revealed that the engine had been in service for over 44 years without ever undergoing a complete overhaul, having only received partial inspections. Investigators found that the engine's maintenance schedule, specifically the calendar-based inspections (OMC), had been inconsistent, with the most recent inspection performed over three years late.
Technical analysis of the engine showed severe internal damage, including fractured engine casing and broken connecting rods. The investigation also noted that the engine had experienced long periods of inactivity without following the manufacturer's recommended preservation procedures, which is particularly critical for aircraft operating in high-humidity coastal environments.
Findings
- The engine failure was caused by the breakage of internal rotating elements due to operating without adequate lubrication.
- The loss of oil pressure was likely caused by a structural failure of the engine casing, potentially exacerbated by the recent maintenance work that restored cylinder compression levels.
- The engine's maintenance history was irregular, failing to strictly adhere to required calendar-based inspection intervals.
- Inadequate engine preservation during extended periods of inactivity left internal components vulnerable to corrosion and degradation.
- The engine had operated for over four decades without a full overhaul, relying only on partial inspections.