New F-15EX Jet’s First Flight Clears Path for Deliveries to U.S. Air Force Our Bureau 1857 F-15EX fighter's maiden flight The new Boeing F-15EX fighter jet completed its first flight today, paving the way for the early delivery of the first two jets to the U.S. Air Force later this quarter. In July, the Air Force awarded Boeing a contract to build the first lot of eight jets. Future plans call for as many as 144 aircraft. The jet took off and landed from St. Louis Lambert International Airport, completing a 90-minute test flight before returning to the airport.