What happened
On February 14, 2006, a SOCATA TB20 Trinidad GT, registration CS-DEO, was conducting a visual flight rules (VFR) instructional flight from Évora to Portimão. The aircraft was occupied by a student pilot, an instructor, and a second student pilot acting as a passenger.
After completing a visual circuit at Portimão Aerodrome, the student pilot performed an approach to runway 29. The landing was long, touching down in the second third of the runway, and was characterized by an approach speed exceeding the recommended Vref. Upon touchdown, the student pilot applied the brakes aggressively. This caused the aircraft to veer to the left, resulting in the burst of the left main tire. As the instructor took control and applied opposite rudder to correct the heading, the right main tire also burst due to the dynamic forces and high speed. The aircraft eventually came to a halt on the left side of the runway. There were no injuries and no damage to third parties, though the aircraft sustained damage to its main gear tires.
The investigation
The GPIAAF investigation examined the flight history, meteorological conditions, and the actions of the crew. The investigation established that the weather conditions were favorable, with calm winds, clear skies, and high visibility. The investigation also reviewed the aircraft's maintenance and documentation, finding all certificates and licenses to be valid. Witnesses at the aerodrome noted that the approach speed appeared higher than the standard Vref and that the landing was long.
Findings
- The approach speed was higher than the ideal Vref.
- The landing was long, occurring in the second third of the runway.
- The student pilot applied aggressive braking during the landing phase.
- The simultaneous bursting of the tires was caused by the combination of excessive speed and the dynamic forces exerted on the tires during the sudden change in the aircraft's trajectory.
- The instructor's failure to intervene during the unstable approach allowed the situation to develop.