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By Andrea Shalal
WASHINGTON, March 7 (Reuters) - The U.S. Air Force on Mondaynamed Pratt & Whitney as the engine maker for the new NorthropGrumman Corp long-range strike bomber, and defended theplane's "cost plus incentive fee" contract that has beenchallenged by U.S. lawmakers.
U.S. Air Force Secretary Deborah James revealed the names ofthe engine maker, a unit of United Technologies Corp andother key suppliers at a Pentagon news conference amid growingcalls for more transparency about the classified arms program.
Other key suppliers for the new B-21 bomber include the U.S.units of two British suppliers, BAE Systems Plc and GKNPlc, as well as Spirit AeroSystems Holdings Inc,Orbital ATK Inc, Rockwell Collins Inc and JanickiIndustries, a family-owned company, James said.
Boeing Co and Lockheed Martin Corp last monthdropped their challenge to the multibillion-dollar bombercontract that Northrop won in October.
James said the suppliers named Monday would work on theairframe and mission systems of the new flying wing stealthbomber, but gave no details.
Lieutenant General Arnold Bunch, the Air Force's topmilitary acquisition official, declined to say where Northropwould assemble the planes.
He said the Air Force hoped in time to provide the value ofthe bomber development contract and associated incentive fees.
He said the incentive fees were based on cost andperformance, with an emphasis on meeting plans to start usingthe new planes in combat from the mid 2020s.
The Air Force initially estimated it would cost $23.5billion to develop the new bomber, but has not released terms ofits contract with Northrop. Analysts have said the overall dealcould be worth $80 billion to Northrop and its suppliers overtime.
James said the Air Force was working to address questionsraised by Senate Armed Services Committee Chairman John McCainabout the Northrop contract. McCain fears it could leave theU.S. government liable for potential cost increases.
She said it would take "money and time" to cancel and redothe deal if McCain succeeds in blocking it.
McCain says the Air Force has been spared from $1 billion incost overruns on a new refueling plane being built by Boeingsince that plane was developed under a fixed price contract.
But Bunch said this program was different since it involveda wholly new airplane, and the company had no potentialcommercial or foreign military sales customers to help defrayits costs. (Reporting by Andrea Shalal; Editing by Bill Rigby and TomBrown)