Pilot

"Now we're talkin"
 * USA Pilot

'Pilot' is a generic term for anyone operating a vehicle; however when most US commanders referred to a 'Pilot,' they were referring to Pilots who had survived the destruction of US vehicles. US vehicles had titanium-plated cockpits and US aircraft equipped their pilots with parachutes, giving them a good chance of survival. Since Pilots able to survive such destruction were highly skilled, they were deemed a valuable asset. If they could be escorted to another vehicle they could show its crew what they had learned on the battlefield, making the crew more efficient.

Counters
Being unarmed and poorly armored, any attack would likely kill them, in spite of the fact that they were fast runners. Quad Cannons and Gattling Tanks could easily chase down and slaughter Pilots before they had a chance of getting to another vehicle, or even kill them while they were still in the air. Killing an enemy Pilot was a smart move, because the more units a pilot has been in the more experience he brings to his next vehicle.