What happened
On November 16, 2011, an Air France Boeing 777-200, registration F-GSPP, was performing an automated CAT3 approach to runway 08R at Paris Charles de Gaulle. Due to low visibility conditions, Low Visibility Procedures (LVP) were in effect. During the approach, an amber 'NO LAND 3' alarm appeared on the EICAS, indicating a degradation of landing capabilities. Following company procedures, which mandate a go-around for any such alarm below 1,000 feet, the crew initiated the maneuver.
During the execution of the go-around, the pilot flying (PF) unintentionally pressed the auto-throttle disconnect switches instead of the TOGA switches. While the pilot increased thrust, the aircraft's pitch began to decrease, and the airspeed increased. For several seconds, the crew failed to monitor flight parameters effectively, and the autopilot continued to command a nose-down pitch. The aircraft's vertical acceleration reached 1.84 g during the period of instability. Eventually, following prompts from the relief pilot, the crew applied simultaneous pitch-up inputs, stabilizing the aircraft and allowing the maneuver to continue successfully. The landing was subsequently completed without further incident.
The investigation
The investigation relied on data from the Quick Access Recorder (QAR) and Flight Data Recorder (FDR), as well as crew testimonies. The investigators examined the sequence of events through four distinct phases: the initial alarm and crew reaction, a period of unmonitored flight deviation, the corrective pitch inputs, and the final stabilized go-around. The investigation also reviewed the crew's experience, the prevailing meteorological conditions, and the airline's specific operational procedures for CAT3 approaches and go-arounds.