Executives from F135 engine-maker Pratt & Whitney estimate that they will have retrofitted the program's 21 test aircraft with an interim engine fix by January of next year. Bennett Croswell, president of Pratt's military engine business, told reporters during a Sept. 15 news briefing at the Air Force Association's annual conference in National Harbor, MD, that the company -- working with the F-35 joint program office and prime contractor Lockheed Martin -- is close to validating the root cause of...