B-21 Still on Track for First Flight This Year. But Are There Enough in the Pipeline? Sept. 13, 2023 | By John A. Tirpak While the Air Force eagerly awaits the first flight of the B-21, there aren’t enough Raiders behind that first aircraft in the pipeline to do everything the nation needs the bomber fleet to do, a top analyst said Sept. 13 at AFA’s Air, Space & ...