What happened
On March 29, 2013, an Airbus A321, registration SX-BHS, operated by Hermes Airlines, was performing a scheduled passenger flight arriving at Lyon Saint-Exupéry Airport. The flight was operating under Low Visibility Procedures (LVP) due to fog and rain.
During the ILS approach to runway 36R, the crew failed to verify the navigation database, resulting in the aircraft remaining tuned to the ILS frequency for Ajaccio rather than the active Lyon runway. As the aircraft descended, the crew's attention was diverted by managing the incorrect frequency and navigating the localizer. This led to an unstabilized approach where the aircraft was neither properly configured nor on the correct flight path.
At a low altitude, the aircraft's vertical guidance was mismanaged, and the crew selected a target altitude of 400 ft, despite the airport elevation being 880 ft. This error, combined with an inappropriate descent, triggered a Ground Proximity Warning System (GPWS) 'PULL UP' alert. During the subsequent emergency maneuvers, the instructor and the student pilot provided conflicting control inputs, leading to a 'DUAL INPUT' alarm and significant fluctuations in the aircraft's pitch and altitude.
The investigation
The BEA examined flight data from the FDR and CVR, air traffic control recordings, and crew testimonies. The investigation focused on the crew's management of the approach, the impact of low-visibility procedures, and the effectiveness of the emergency maneuvers. The investigation also scrutinized the training and experience levels of the crew, noting that the student pilot was in line training with only 25 hours of experience on the A320 type, and both pilots were highly experienced on the Boeing 737, which features a different control logic.