Could someone explain why there is still an "Allegheny Airlines" and a "PSA" and a "Piedmont" as part of the US Airways system? All three of these carriers are wholly owned subsidiaries of US Airways Group Inc, and are dba as US Airways Express. But, why are these names still in use? Especially "PSA" operating out of Dayton, Ohio. That's an oxymoron if I've ever heard one.
Why can't they just let bygones be bygones? I assume there is some "legalese" involved here?