Earlier quoted context omitted.
No. Windows boxes can communicate to an RTOS like VxWorks over a network just fine.
The level of performance needed in the GCS is even less than you might think, too -- for most of the UAVs, you don't have direct flight controls -- it's more like a naval ship, where you instruct it to go to certain altitude and fly a flight path you plot on a map. Some of them have more stick/rudder style controls, mainly for landings, which are often controlled by another operator physically at the launch/recovery…
Woah, what Navy has ships like that? Bowser's navy?
But yah, I know what you're talking about.