Pentagon acquisition chief John Young might not approve the production of seven Navy F-35 Joint Strike Fighters until aircraft builder Lockheed Martin and engine maker Pratt & Whitney certify short-take-off-and-vertical-landing power plants for flight, he told reporters today. Noting that last week's Defense Acquisition Board meeting on whether to approve phase three of low-rate initial production "was a fairly successful and productive discussion," Young said he would likely approve the production of seven Air Force conventional jets. "I'm anxious for...