Aerial view of Ariane-5 launch pad and surrounds at the European Spaceport

Flight Operations, also known as 'Flight Ops', are a very complex set of written rules and procedures. They are essential for a complex mission such as the ATV, to bring together its logistics, its ground segment - including control centres, launch, tests and training facilities, its contingencies and its different scenarios.

For the ATV, Flight Ops are quite elaborate since they involve:

• Kourou, ESA's launch site in French Guiana where the ATV takes off on top of an Ariane-5. The early mission software sequences are loaded onto ATV at the launch site.

• ATV Control Centre (ATV-CC) in Toulouse, France, from where a ground team controls the ATV mission.

• Mission Control Centre in Moscow (MCC-M) because ATV docks with the Russian segment of ISS, which takes control 'most of the time' of the ATV-ISS joint operations during the six-month docked phase.

• Mission Control Center in Houston (MCC-H), which is responsible for the entire ISS and coordinates overall ATV-ISS joint operations.

• Crew, who are in charge of monitoring tasks during the ATV rendezvous and cargo transfer during the docked phase.

ATV-CC is able to communicate with ATV to control and monitor its behaviour and performance, in real-time, and when needed, to send commands. The communications between the ATV Control Centre and ATV itself are routed either via NASA relay satellites, or by the European relay satellite Artemis. Both paths are available at all times.

The Flight Control Room of the ATV Control Centre, Toulouse, France

Pre-programmed sequences

Since the ATV is a highly automated spaceship, the task of the ground controllers is essentially to monitor the ATV in flight and, at predefined steps, to send 'Go' commands to the spaceship in orbit for onboard pre-programmed sequences.

The ATV is loaded with Onboard Mission Plans, which automatically run software sequences, controlling the ATV configuration mission and off-nominal scenarios. However some Onboard Mission Plans, which correspond to the flight to be flown, are up-linked by the ATV-CC to the ATV sequentially as the mission goes on, with the proper data corresponding in particular to the manoeuvres that the ATV shall perform.

Down on Earth, this remote surveillance mission requires a huge and complex ground infrastructure. In case of off-nominal situations, the role of the ATV-CC is to understand what went wrong and to implement proper solutions to recover the mission, for which controllers operating the ATV-CC are trained.