Picture a future crewed mission in the far reaches of the solar system, supported by a fleet of uncrewed spacecraft. Some might drift so far apart that they’re no longer visible to one another. Even so, one person is expected to monitor them all from afar.
Even when the spacecraft operate autonomously, someone needs to watch for malfunctions and possible collisions. So how many can one person manage without losing sight of the bigger picture? A 2010 document offers a surprising answer: it depends heavily on how demanding the mission is.
A Fleet With Different Jobs
Written at the Defense Intelligence Agency, the U.S. Department of Defense’s intelligence agency, the document describes a hypothetical future crewed mission. Its supporting fleet could include reconnaissance, research, and mineral-mining spacecraft. Others might shield the crew from radiation or search for approaching objects.
Many of the spacecraft would navigate and carry out tasks autonomously. But they could still malfunction or risk colliding, so someone would need to monitor them. At times, the supervisor might also have to direct them. Even when a spacecraft moves out of sight, the supervisor needs to know where it is and what it’s doing.
Why Does the Number Drop?
To estimate how many vehicles one person could manage, the document reviewed studies on supervising aircraft and remotely controlling uncrewed vehicles. These were not experiments in space. Models developed for those fields suggest that one person could oversee about 16 vehicles on simple missions, such as tracking or selecting a target. On moderately difficult missions, which require more control or task execution, the number falls to about seven. On complex missions, where the vehicles perform different roles, it drops to about four.
These figures don’t come from testing a group of spacecraft together. They are estimates based on studies in related fields that examined how people supervise and control multiple vehicles at once. The basic idea is that a person needs to keep track of each vehicle’s location, mission, and direction of travel. The document calls this “the big picture.”
Screens and automation can help someone keep track. The document also suggests monitoring physical changes, such as heart rate, to detect in real time when the workload becomes too much.
What We Still Don’t Know
