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The European Space Agency (ESA) is preparing for an unprecedented launch, during which two satellites – FLEX for photosynthesis research and Sentinel-3C for Earth monitoring – will go into space on a single carrier. The uniqueness of the event lies not only in the joint launch, but also in the parallel operation of two independent mission management teams, working side by side to ensure the success of both projects. This is a complex challenge that requires coordination and readiness for surprises.
“Team of Teams” in action: a rehearsal for the future
On 15 September, a launch vehicle will launch two satellites from the Kourou spaceport in French Guiana: FLEX, ESA’s mission to study photosynthesis on Earth, and Sentinel-3C, a new Copernicus satellite that will monitor the oceans, land, glaciers and atmosphere of our planet. At ESA’s Space Operations Centre (ESOC), two separate teams are already busy preparing to operate the satellites. The side-by-side rehearsals are not only aimed at preparing for their own missions, but also at working out when the operations of the two spacecraft might overlap. Each mission requires a large team of engineers, flight dynamics specialists, ground station operators, software developers and project teams. Preparing one satellite for launch is already a complex process, and ESA is preparing all this for two missions at the same time.
Challenges of parallel work and shared resources
“Launching two satellites is not the most difficult thing. We have done similar things before, such as ESA’s Herschel and Planck missions in 2009, but they were managed by a single, integrated team,” explains Franco Marchese, ESA’s head of flight operations for the launch and early orbit phase of Sentinel-3C. “What makes this launch special is that we have two teams working in parallel, and the satellites will be flying virtually in the same orbit. This is a real challenge.” ESOC is one of the few mission control centres in the world capable of handling such a task. For Sentinel-3C and FLEX, two full teams are preparing to work side by side. Each has its own flight management team, ground station operations team, flight dynamics team and project teams focused on their respective spacecraft. Although the teams prepare and operate independently, their activities overlap at key points. Some resources and support teams are shared, and certain activities require close coordination between missions. This means preparing not only for the needs of each individual mission, but also for situations where both teams may need access to shared resources at the same time or must respond simultaneously.
Simulations: practicing every second
Long before the spacecraft reaches the launch pad, mission teams undergo a simulation phase – a series of highly realistic training exercises that allow the “team of teams” to practice responding to both routine and unexpected situations. These rehearsals often last for several days, similar to the real early orbit phase. Teams practice typical and emergency scenarios, including satellite anomalies, orbit definition problems, ground segment failures and other operational contingencies. But simulations are not just about testing systems and procedures. “Simulations are not just about the technical side,” says Emily Brannan, ESA’s simulation officer for Sentinel-3C. “There’s also a human aspect.” They give teams the opportunity to practice communication, decision-making under pressure and coordination across disciplines before they do so with real satellites in orbit. Special attention is paid to situations that could affect both missions at the same time. “Teams have to remember that anything that happens to their spacecraft could have consequences for the other mission,” explains Gustavo Baldo Carvalho, ESA’s simulation officer for FLEX. “What if they suddenly need the same resource at the same time? These are the situations that we make teams think about during the simulations.”
