As the F-35 Joint Strike Fighter transitions from its development phase to follow-on modernization, the Air Force, Navy and Marine Corps are seeking a total of $587 million in fiscal year 2018 to support F-35 Block 4 development -- more than double what they requested in FY-17. International partners are also chipping in $212 million, bringing the total projected Block 4 funding for FY-18 to $799 million, according to budget documents. The services' requests come after two subsequent years of...