What happened
On March 11, 2013, an Air France Airbus A320-214, registration F-HBNE, was performing a scheduled passenger flight from Marseille to Paris Charles de Gaulle. While approaching Marseille Provence Airport, the crew accepted a request from Air Traffic Control for a relatively short visual approach to runway 31L.
During the base leg, the pilot flying (PF) decided to transition to full landing configuration early. During the final turn, the PF executed a prolonged pitch-up command to correct for a perceived high approach, which caused the airspeed to drop below the target. This led to the activation of the "SPEED, SPEED, SPEED" low-energy alarm, followed by the Alpha Floor protection mode and the TOGA LOCK feature. The crew subsequently performed a go-around and eventually landed the aircraft normally on a subsequent approach.
The investigation
The BEA examined flight data from the maintenance recorder (QAR), radio communications, and crew testimonies. The investigation focused on the flight management system (FMS) behavior, the crew'-s approach stability, and the effectiveness of the automated protections. Investigators also reviewed the crew's workload, fatigue levels, and the impact of non-standard approach procedures requested by ATC.
Findings
- The primary cause was a prolonged pitch-up maneuver during a turn, which occurred while the aircraft had low energy reserves due to its high-drag configuration and low airspeed.
- The crew implemented a non-standard, shortened visual approach that had not been specifically briefed or prepared for.
- The pilot flying was experiencing fatigue and had requested monitoring from the pilot monitoring (PM).
- The PM failed to intervene or announce significant deviations in descent rate or airspeed loss.
- The crew's task distribution was ineffective, as the PF was poorly positioned to maintain visual contact with the runway.
- An internal FMS reset occurred during the approach, causing a temporary reversion in speed mode, though its direct contribution to the incident could not be definitively established.
- The crew's reliance on automation led to a hesitation in manual thrust adjustment when the low-speed alarm first sounded.