NEW YORK - The Official Committee of Unsecured Creditors in the Chapter 11 bankruptcy of AMR Corp., the parent company of American Airlines Inc., on Aug. 8 filed a brief in support of confirmation of the airline's second amended joint Chapter 11 plan that is premised on the proposed merger of American Airlines and US Airways Inc. (In Re: AMR Corporation, No. 11-15463, Chapter 11, S.D. N.Y. Bkcy.).