Final assembly building
(BAF, for "Bâtiment d'Assemblage Final"). The last stage in a launch campaign is when Ariane 5 is transferred by rail to the Final Assembly Building which is 90 metres high.
Inside this building the launcher receives its payload and the Sylda or Speltra supporting structures (if required), and the fairing. These payload components are prepared in an encapsulation hall in the Final Assembly Building.
The payload is hoisted up by a mobile crane and transferred to the top of the launcher for installation.
The umbilical tower on the launch pad has a 20 metre extension that includes the connections for the fairing air conditioning system.
The EPS (Étage à Propergols Stockables or Storable fuel stage) and the launcher attitude control system are loaded with fuel in the Final Assembly Building. Once all the parts have been assembled in the Final Assembly Building, the mobile launch pad with the complete launcher is taken to the Launch Zone (ZL, Zone de Lancement). This stage is carried out 12 hours before the launch.