I was always under the impression that unless in BK a company simply couldn't drop another companies contracts. You purchase a company you purchase their debts and other obligations (contracts). Hence CHQ flying for AMR. AMR purchased TWA which CHQ had a contract with. I didn't major in business though. If I'm wrong on what happens in a merger/acquisition or in the history of the company feel free to correct me. I'm a little light headed at the moment from the pain killers