What happened
On October 10, 2012, an Embraer EMB-500, registration PR-PNM, was performing a private passenger flight from Rosário, Argentina, to Porto Alegre, Brazil. The aircraft was carrying one pilot and four passengers.
During the landing roll at Porto Alegre Airport (SBPA), the aircraft gradually drifted to the right, eventually exiting the paved surface. Once on the grass area, the aircraft struck a concrete box, which caused the nose gear to collapse, and subsequently struck another concrete structure, bringing the aircraft to a final stop. The impact caused substantial damage to the fuselage, radome, wings, flaps, landing gear, and various antennas. All five occupants escaped the accident without injury.
The investigation
CENIPA investigators analyzed data from the Cockpit Voice and Data Recorder (CVDR) and the Brake Control Unit (BCU). The investigation established that the aircraft crossed the runway threshold at 50 feet with a speed of 106 knots, which was 8 knots above the reference landing speed (VREF).
Data indicated that the aircraft experienced wind gusts during both the final approach and immediately after touchdown. While the pilot applied the brakes for approximately 2.4 seconds, the investigation found that the right side of the aircraft was not experiencing sufficient weight on the wheels (WOW) due to a lateral tilt. This lack of downward pressure on the right strut caused the anti-skid system to reduce braking pressure on the right side to prevent a skid. Furthermore, the investigation noted that after the initial braking application, the pilot did not apply further braking, even differentially, and likely attempted to correct the trajectory using only the rudder.
Findings
- Adverse meteorological conditions: The aircraft encountered crosswind gusts from the right. While the reported winds were within the aircraft's operational limits, the gusts contributed to a significant deviation in the aircraft's heading, which increased to 126 degrees during the landing roll.
- Control inputs: The pilot's application of controls contributed to the excursion. The aircraft's primary aerodynamic controls had reduced effectiveness due to the low speed at touchdown, and the pilot failed to use differential braking or sufficient rudder input to correct the deviation after the initial braking period ended.