Editing Mars Express (section)

=== Mission preparation ===
In the years preceding the launch of a spacecraft numerous teams of experts distributed over the contributing companies and organisations prepared the space and ground segments. Each of these teams focussed on the area of its responsibility and interfacing as required. A major additional requirement raised for the Launch and Early Orbit Phase (LEOP) and all critical operational phases was that it was not enough merely to interface; the teams had to be integrated into one Mission Control Team. All the different experts had to work together in an operational environment and the interaction and interfaces between all elements of the system (software, hardware and human) had to run smoothly for this to happen:

* the flight operations procedures had to be written and validated down to the smallest detail;
* the [[control system]] had to be validated;
* system Validation Tests (SVTs) with the satellite had to be performed to demonstrate the correct interfacing of the ground and space segments;
* mission Readiness Test with the [[Ground station|Ground Stations]] had to be performed;
* a Simulations Campaign was run.