AoA vanes not just failed, they failed because of incorrect maintenance procedure. >One of the contributing causes was incorrect maintenance procedures which a

AoA vanes not just failed, they failed because of incorrect maintenance procedure. >One of the contributing causes was incorrect maintenance procedures which allowed water to enter the angle of attack (AOA) sensors. During fuselage rinsing with water before painting, three days before the flight, the AOA sensors were unprotected. As specified in the Structure Repair Manual by Airbus, it is mandatory to fit a protection device on AOA sensors before these tasks. In this case several failures all happening at the same time cause the crash: software, pilots following protocols and maintenance.