What happened
On January 16, 1997, a Cessna 310, registration PT-CSN, departed from Franca, São Paulo, en route to Congonhas, São Paulo, carrying six occupants. While performing an instrument approach to the destination, air traffic control lost radar contact with the aircraft. Witnesses near the crash site reported seeing the aircraft flying at a very low altitude before it entered a cloud layer to avoid an obstacle. Radar data later showed the aircraft performing a right-hand turn and descending rapidly. The aircraft eventually struck the ground at an approximately 80-degree angle at high speed near Santana de Parnaí．ba, SP. The impact caused the aircraft to be destroyed and a post-impact fire. All six fatalities occurred at the scene.
The investigation
CENIPA's investigation revealed significant discrepancies regarding the aircraft's maintenance records. While the logbooks indicated the presence of Continental IO-470 engines, investigators discovered that the installed engines were actually IO-520 models. Furthermore, the engine logbooks and identification plates had been falsified. The investigation also noted that the propellers installed were not compatible with the discovered engine models, which could potentially cause thrust asymmetry.
Regarding the crew, the pilot was flying in the left seat for the first time in this specific aircraft. While the pilot held valid commercial and IFR licenses, there was a lack of documented experience regarding instrument flight proficiency. Additionally, the investigation looked into previous reports of total electrical failures occurring during landing gear retraction in this aircraft, though no specific records of repairs for these issues were found.
Findings
- Spatial disorientation is suspected to have occurred as the pilot transitioned into instrument meteorological conditions (IMC).
- The pilot's lack of proficiency in IFR flight was a contributing factor to the loss of control.
- The aircraft's maintenance history was deficient, characterized by falsified engine documentation and mismatched components.
- The investigation could not definitively rule out a total electrical failure as a trigger for disorientation, given the aircraft's history of electrical issues.