What happened
On February 7, 2014, a Cirrus SR22, registration PR-JTP, was performing a takeoff from the Fazenda Perdizes airstrip (SWLR) in Silvânia, Goiás, bound for Curitiba, Paraná. The aircraft was carrying one pilot and two passengers.
As the aircraft approached rotation speed on runway 09, the pilot experienced a sudden leftward yaw. Despite applying full right rudder to correct the deviation, the aircraft continued to drift leftward. Realizing that the aircraft was exiting the runway, the pilot reduced engine power. The left wing subsequently struck a soybean plantation located in the side area of the runway, causing the aircraft to come to a stop. All three occupants escaped the incident without injury, though the aircraft sustained substantial damage to the main landing gear, right flap, right elevator, step, and pitot tube.
The investigation
CENIPA's investigation revealed significant discrepancies between the official aeronautical information and the actual conditions at the airstrip. While the ANAC database listed the runway as a 700-meter gravel surface, the investigation established that the runway was actually a 1,050-meter grass surface with a width of only 12 meters. Furthermore, the runway surface was convex, with the edges being lower than the center.
The investigation found that the grass was approximately 12 cm high, uneven, and had not been recently maintained. The safety margins were critically narrow, as the aircraft's wingspan is 11.67 meters, leaving less than a meter of clearance on either side of the 12-meter wide runway. The investigation determined that the initial deviation was likely caused by irregularities in the runway surface, which then led to the left wing making contact with the tall soybean crops in the unmaintained escape area.
Findings
- The primary cause of the deviation was the inadequate runway width and surface irregularities which provided insufficient safety margins for an aircraft with an 11.67m wingspan.
- The pilot failed to properly assess the operational risks associated with using a narrow, uneven grass runway with encroaching vegetation.
- Inaccurate aeronautical information regarding the runway surface and dimensions was present in official records.
- The lack of maintenance on the runway edges and the presence of tall crops in the safety area contributed to the loss of control.
- Flight planning and pilot judgment were contributing factors in the decision to operate in these conditions.