What really can the co-pilot do in a battle other than just sit there, I have tried looking it up and can't find out what they do and also does anybody know what the middle set on an arc-170 is

There is a whole list of actions in the CRBs. Page 232-237 in the EotE CRB.

A co-pilot can fire weapons, angle shields, co-pilot, etc., and can take over if the pilot is incapacitated.

The second seat in an ARC is the co-pilot/forward gunner, the third is the tailgunner.

A successful Co-Piloting action can downgrade the difficulty of the pilot's... Piloting check. Knocking down a Challenge die from the pool is very helpful indeed.

Not to mention Gunnery, emergency repairs, and more.

So, in short, a co-pilot doubles the amount of actions available (except for, you know, really moving and piloting). Some of my dead characters would have wished for an extra action in damage control or shield angling in a single round.

Thanks for the info, I could seem to find at what the did when reading the rulebooks

Hey @Rimsen , thanks, but don't be sad. It was a blast. Such "going out in a blaze of glory" situations as you would have wanted to see. That brave rebel pilot up against that rival starfighter ace and simply not having that last action to angle deflectors, or use emergency repairs to get that one or two hull trauma back that incapacitated the ship. Age of Rebellion starfighter squadron based games. A "Kaboom!" was to be expected at one time or another.

But it also did show the strength of a copilot. Doubling the amount of actions from within the cockpit, and as such providing that extra combat check, or a shield boost. That sort of colpiloting thing.