An Air France A340-300 nearly crashed while on approach to Paris Charles de Gaulle Airport (CDG) on March 13 last year because the crew failed to understand the danger cues the aircraft’s flight systems were showing them, according to the French BEA accident investigation agency. The aircraft was already above the recommended altitude for glideslope intercept–with speedbrakes deployed–as it was being vectored for the Runway 8R Cat III ILS at CDG. On low-visibility approaches at CDG, ATC procedures also require aircraft to be slowed to less than 180 knots within 15 miles.
Just inside the 17-nm point, the A340 was still indicating 220 knots. Nine miles out, the aircraft was 1,750 feet above the glideslope, and at four miles from the threshold the aircraft was still 2,100 feet above the glideslope and descending. Two miles from the end of the runway, the A340 was 1,600 feet above the glideslope with gear down when the autopilot sensed a problem and changed modes. The nose of the aircraft pitched up 26 degrees and vertical speed increased from 1,600 feet per minute down to more than 3,300 feet per minute up, reducing the airspeed to 130 knots from 163 knots. As the nose of the Airbus pitched up, the crew disconnected the autopilot and pushed the sidestick forward to the stop to reduce the angle of attack.
When the aircraft accelerated, however, the auto-thrust system disconnected. The crew re-engaged the autopilot a few moments later to perform an automated go-around maneuver. The automation re-engaged in speed mode as the aircraft crossed the threshold at 2,700 feet agl. The aircraft then suddenly pitched down and began to descend. The crew again disconnected the autopilot, while also advancing the thrust levers to TOGA (takeoff go-around) and hand flying the aircraft back around to a safe landing.
In addition to faulting the crew for continuing the approach even after realizing they were much too high, as well as not fully understanding precisely what they were telling the aircraft’s automation to do, the BEA also faulted air traffic controllers at CDG for failing to adequately monitor a Cat III approach.