What happened
On March 25, 2016, a Neiva 56-C-1, registration PP-HPL, was conducting a flight instruction mission involving touch-and-go maneuvers at the Araras Aerodrome (SDAA) in São Paulo, Brazil. The flight originated from Rio Claro (SDRK) at flight level 035.
During the third touch-and-go attempt at Araras, the engine lost power and subsequently flamed out while the aircraft was at approximately 100 feet of altitude. The instructor in command took control of the aircraft and performed an emergency landing on the remaining runway length. The aircraft touched down in the final third of the runway and veered to the left, colliding with the aerodrome's perimeter fence. The aircraft sustained light damage, and both occupants escaped without injury.
The investigation
CENIPA investigators examined the aircraft's fuel, lubrication, and ignition systems, but post-accident tests revealed no mechanical defects or operational discrepancies that would justify the engine failure. Meteorological data from the nearby Pirassununga station indicated high relative humidity, a condition known to promote carburetor icing.
The investigation noted that the instructor observed a drop in engine RPM shortly before the failure but did not activate the carburetor heat. While the investigation concluded that the heat system is more effective as a preventive measure than a corrective one, the lack of activation was a factor in the engine's subsequent shutdown.
Findings
- High relative humidity in the area created conditions conducive to carburetor icing.
- The Neiva 56-C-1 is particularly susceptible to carburetor ice formation.
- The pilot's judgment regarding the use of carburetor heat following a drop in RPM contributed to the engine failure.
- The engine failure occurred at a low altitude (100ft), leaving insufficient time to identify and rectify the cause before the engine flamed out.