PHILADELPHIA, PA. -- Boeing officials plan to seek clarity from the Air Force about changes included in the latest draft request for proposals in the competition to replace the UH-1N Huey fleet, saying they’re unsure why the service is pushing certain requirements and seem to be pursuing a development program rather than an off-the-shelf procurement. But the defense giant, which hosted reporters at its Italian bid partner Leonardo’s facility here Monday, is undaunted by the Air Force’s shift to a...