Rolls-Royce Corp., Indianapolis, Ind., is being awarded a $52,267,510 modification to a previously awarded firm-fixed-price contract (N00019-10-C-0020) to exercise an option for engine sustainment services for V-22 AE1107C engines in support of the U.S. Marine Corps and the U.S. Air Force.  The services to be provided include low power repairs, turboshaft engine support and fleet site support.  Work will be performed in Indianapolis, Ind. (80 percent), and Oakland, Calif. (20 percent), and is expected to be completed in November 2013.  Contract funds in the amount of $52,267,510 will be obligated on this award of which $50,378,962 will expire at the end of the current fiscal year.  The Naval Air Systems Command, Patuxent River, Md., is the contracting activity.