What happened
On July 24, 2010, an EMB 711ST aircraft, registration PT-RLK, was performing a passenger transport flight from São Luís to Pinheiro, Brazil. The flight path was diverted to the municipality of Matinha to pick up three passengers. The landing strip used in Matinha was neither registered nor homologated by the Brazilian National Civil Aviation Agency (ANAC).
During the takeoff roll, after rotation, the aircraft was struck by a strong right crosswind. This wind caused the aircraft to drift toward the left side of the runway. The pilot attempted to apply right rudder to correct the deviation, but was unable to maintain the centerline. Consequently, the left wing of the aircraft collided with soccer goalposts located approximately three meters from the edge of the runway. The impact caused severe damage to the engine, wings, flaps, ailerons, and the propeller.
All four occupants—the pilot and three passengers—escaped the accident without injuries.
The investigation
CENIPA's investigation focused on the circumstances leading to the loss of control. The investigation established that the aircraft was within its weight and balance limits, though it was operating near its maximum takeoff weight. The investigation also noted that the pilot had intentionally deviated from the filed flight plan to land at an unauthorized aerodrome.
Investigators examined two possible aerodynamic hypotheses for the loss of control: either the aircraft had rotated before reaching sufficient airspeed to maintain directional control against the crosswind, or the strong wind caused the right wing to lift prematurely, inducing a roll toward the left. The investigation also noted that the lack of official wind indicators, such as a windsock, at the unregistered site contributed to the pilot's inability to anticipate the wind conditions.
Findings
- Flight indiscipline: The pilot intentionally operated at an unregistered and unhomologated aerodrome, violating aviation regulations.
- Inadequate flight planning: The pilot failed to consider the safety risks of operating at an uncertified landing site that lacked minimum safety infrastructure.
- Environmental factors: A strong right crosswind significantly impacted the aircraft's stability during the critical rotation phase.
- Managerial oversight: The aircraft owner permitted the operation of the aircraft at an unauthorized landing site.
Safety action
CENIPA issued several safety recommendations following the investigation:
- To the aircraft owner: To participate in theoretical courses regarding aerodynamics, specifically focusing on longitudinal, directional, and lateral stability.
- To the Mayor of Matinha: To prohibit aerial operations at the local landing strip until it is properly registered and meets ANAC infrastructure requirements.
- To ANAC: To disseminate the final report to general aviation operators to emphasize the necessity of using only registered and homologated aerodromes.