What happened
On September 12, 2011, an Air France Airbus A321-211, registration F-GTAT, was performing a scheduled domestic flight from Marseille Provence to Paris Charles de Gaulle. The approach was stabilized on the ILS 26L runway until approximately 50 feet above the ground. However, as the aircraft descended below 100 feet, it encountered a significant wind shear effect, with the headwind component dropping from 17 knots to 4 knots in just eight seconds.
This sudden change caused the aircraft's airspeed to decay below the target speed. At approximately 20 feet, the pilot flying (PF) experienced a sensation of the aircraft sinking and responded with a reflexive, full-aft input on the side stick. This action increased the aircraft's pitch to approximately 8.4 degrees, causing the main landing gear to strike the runway firmly with a load factor of 1.9g. This impact triggered a bounce.
During the subsequent bounce, the deployment of the spoilers further increased the pitch angle to a maximum of 9.1 degrees. The aircraft subsequently made a second touchdown with an excessive pitch attitude, resulting in the scraping of the lower fuselage between frames 62 and 67 and damage to the rear drainage mast.
The investigation
The investigation focused on the flight parameters, the crew's actions, and the aircraft's configuration. Investigators analyzed the flight path, noting that while the approach was stabilized, the crew had manually disconnected the autopilot and autothrust earlier in the descent. The investigation also examined the cockpit environment, noting that the aircraft was not equipped with optional visual or audible pitch limit alerts. Furthermore, the investigation looked into the crew's training, specifically regarding the aerodynamic differences between the A320 and the longer-fuselage A321.
Findings
- A significant decrease in headwind occurred during the final stages of the approach, leading to a drop in airspeed below the minimum required speed.
- The pilot flying executed a reflexive full-aft stick input to counter a perceived sink rate, which induced the initial bounce.
- The pilot non-flying (PNF) failed to announce the airspeed deviation or the excessive pitch angle.
- The deployment of spoilers during the bounce contributed to the increase in pitch attitude.
- The aircraft lacked optional cockpit alerts that would have notified the crew of the excessive pitch.
- There was a lack of specific training regarding the unique pitch limitations of the A321 compared to the A320.