The Boeing Co. is quietly pitching the U.S. Air Force a new F-15 jet fighter jet using the same business strategy that convinced the Trump administration to buy more F/A-18E/F Super Hornet jet fighter-bombers for the U.S. Navy. Dubbed the F-15X, the new variant of the venerable F-15 jet offers modern flight controls, cockpit displays, and radar, say military and industry sources with knowledge of the plan. The plane also would pack a lot of firepower, carrying more than two dozen air-to-air missiles, the most of any U.S. Air Force aircraft. Boeing officials declined explicitly to confirm their efforts to sell the F-15X, except perhaps obliquely. The Air Force has not purchased new F-15s since placing a 2001 order for five F-15E Strike Eagles, a two-seat version that can bomb ground targets and shoot down other aircraft. The original F-15 first flew in 1972, and many of the Air Force’s current air-to-air Eagles entered service in the 1980s. Many of them are older than the pilots who fly them.