Exclusive: U.S. Air Force to work on alternative GPS ground system

By Andrea Shalal WASHINGTON (Reuters) - The U.S. Air Force will continue work on an alternative ground control program and explore outside options to hedge against further cost spikes and delays on Raytheon Co's troubled ground control system for next-generation GPS satellites, according to an Air Force document seen by Reuters. The Air Force on Tuesday said a "deep dive" review led by the Pentagon's chief arms buyer last week resulted in a further two-year delay in completion of the Raytheon pr