FARNBOROUGH, ENGLAND -- The use of international partners is paying dividends during the F-35 Joint Strike Fighter's system design and development phase and may enable the Air Force, Navy and Marine Corps to receive refunds for some funding they invest, top program officials say. Similar to the accounting strategy used during the production phase, SDD was set up without a dependence on the international investment that has come flowing in. SDD was budgeted with U.S. funds and $2 billion in...