What happened
On February 1, 2013, a Reims/Cessna FRA 150L was conducting a flight training mission departing from Rome Urbe Airport. During the initial climb, at approximately 800 feet, the crew noticed slight engine vibrations. Upon reaching 1,200 feet, the instructor attempted a magneto check, which revealed that switching to the right magneto resulted in no change in engine RPM.
While attempting to return to the airport, the engine experienced a power loss followed by a total shutdown. The instructor identified a nearby field and executed a forced landing. Upon impact with the ground, the aircraft struck the terrain with a high vertical velocity and a nose-down attitude, causing the nose gear to collapse and the aircraft to flip onto its back. The two occupants, an instructor and a student, escaped the wreckage without injuries.
The investigation
The ANSV examined the wreckage and the engine components. The investigation found no mechanical failures or broken parts within the engine or the fuel system. The fuel tanks and carburetor bowl were empty due to fuel spilling from the vents while the aircraft was overturned.
Meteorological analysis showed that at the time of the incident, the ambient temperature was 13°C with a dew point of 8°C. These conditions, combined with the temperature drop that occurs during air passage through the carburetor, created a high risk for ice formation. The investigation also noted that the crew did not implement the carburetor icing procedures outlined in the flight manual, nor did they fully follow the prescribed emergency landing checklist during the forced landing.
Findings
- The engine shutdown was caused by carburetor icing.
- The crew did not apply the required carburetor icing mitigation procedures.
- The forced landing procedure was not fully executed according to the flight manual.
- The aircraft struck the ground with high vertical speed and a nose-down pitch, leading to the structural failure of the nose gear and the subsequent capsize.