Well, well, well ... already 44 posts on a thread that has started with a very dubious translation of the BEA report by The Aviation Herald.
BEA :
Incident
20/07/2012 AD Paris Charles de Gaulle(95)
Passage sous la vitesse d'évolution en approche, déclenchement de la protection grande incidence
Vol AD Bordeaux Mérignac (33) - AD Paris Charles de Gaulle (95). Lors de l'approche, pilote automatique engagé et A/THR déconnectée, l'avion passe en dessous de la vitesse
d'évolution. Le pilote automatique se déconnecte à la suite de l'activation de la protection grande incidence ''ALPHA PROT". L'équipage reprend les commandes, réajuste la
poussée et atterrit normalement.
The Aviation Herald :
Incident: Air France A321 at Paris on Jul 20th 2012, speed drops to alpha floor on approach
By Simon Hradecky, created Wednesday, Sep 12th 2012 16:34Z, last updated Wednesday, Sep 12th 2012 16:34Z
An Air France Airbus A321-200, registration F-GTAN performing flight AF-7633 from Bordeaux to Paris Charles de Gaulle (France), was on final approach to Charles de Gaulle's runway 26L with autopilot and autothrust engaged, when autothrust disconnected and the speed decayed until the alpha floor protection activated accelerating the engines to takeoff/goaround thrust and disengaging the autopilot. The crew took control, stabilized the aircraft and continued for a safe landing on runway 26L.
The BEA reported in their weekly bulletin of Sep 11th that the autothrust system had disengaged permitting the airspeed to decay to a point where the alpha floor protection activated, disengaged the autopilot and accelerated the engines. The crew took manual control and continued the landing. The BEA is investigating the serious incident.
So it appears that autothrottle was off "A/THR déconnectée" and has NOT "disengaged" on its own and that it is not considered as a "serious incident" by BEA but just as an incident.