The Senate Armed Services Committee has approved a defense policy bill, that if enacted, would require the F-35 Joint Strike Fighter's follow-on modernization program to be classified as a major defense acquisition program and put a 2019 expiration date on the joint program office. The F-35 follow-on modernization program -- also known as Block 4 -- is estimated to cost more than $8 billion for the first block upgrade. The committee states in its summary that classifying Block 4 as...