raf fairford england u.s. department defense lockheed martin corp final stag negotiations two contract 160 fighter jet tandem deal value 14 billion pentagon f-35 program manager say saturday end game air force lieutenant general chris bogdan say interview royal international air tattoo world large military airshow six f-35 lightning ii jet fly week bogdan say agreement could finalise soon decline predict could announce farnborough international airshow next week say major issue resolve fate deal largely lockheed hand moment lockheed f-35 program manager jeff babione tell reporters thursday expect reach agreement soon contract ninth 10th production contract new warplane source familiar two contract say would likely value 14 billion 15 billion babione say price f-35a conventional takeoff land version jet would drop 100 million per plane 10th low-rate production batch include engine build pratt whitney unit unite technologies corp. bogdan say continue work block buy deal international partner 379 billion warplane project large arm program world part large effort drive jet cost buy large number jet time start 12th production batch jet could generate save billion 2.8 billion even u.s. military able join get congressional approval say u.s. military service would likely join start 13th 14th production lot would reduce initially anticipate save hundreds millions dollars say bogdan tell reporters program office carefully assess potential impact trade tariff stem britain vote leave european union initial expectation would much impact drop value british pound could help low cost since 15 percent jet build uk firm pentagon say near deal lockheed f-35 fighter jet