Q to CRJ operators on APU Failure procs.
 

Why do the CRJs need to be 50nm to the shore when they experience an APU failure?

I thought even one working generator is good enough for flight, so if one fails you still have one more spare.

I could understand that if an engine generator fails the situation might be more critical. However i cannot seem to understand the need for an APU once airborne. Also isn't the ram pressure on the turbines enough to restart an engine?

Do crj's not have Ram Air Turbines?

thks.

Thanks a lot for the detailed answer, now I understand much better.

brgds