Main cryogenic stage
Most of the equipment is located on top of the main cryogenic stage. This includes most of the basic electrical equipment, the guidance and telemetry systems and the attitude control system.
The Vulcain is ignited on the launch pad and is monitored for seven seconds. It provides over 116 metric tonnes of propulsion in vacuum.
The main cryogenic stage burns out in less than 600 seconds. After use, the empty stage falls back into the atmosphere and into the ocean.
The main cryogenic stage is a central part of Ariane 5 and is key to the launcher's propulsion; it contains most of the electrical and guidance systems. It carries a load of 132.27 metric tonnes of liquid oxygen and 25.84 metric tonnes of liquid hydrogen for the stage's main Vulcain engine.
The stage is 30.5 metres tall from the main Vulcain engine nozzle to the top part. Its dry mass is 12.2 metric tonnes, and its mass at takeoff with the cryogenic fuel is 170.3 metric tonnes.