Steve Trimble responds: Lockheed Martin flew the first weight-optimized F-35, known as “BF-1,” on June 11, 2008. The first Lockheed Martin F-22, bearing tail number 4001, flew on Sept. 7, 1997, or about 6.5 years after contract award. Finally, Northrop flew the original B-2 on July 17, 1989, or about eight years after winning the contract. For the B-21, the Air Force would like to move faster. One clue is in the name of the organization managing the program: the Rapid Capabilities Office. Upon contract award in October 2015, the Air Force also emphasized that the B-21 would mainly leverage existing technologies, in hopes of avoiding lengthy delays caused by high-risk technology glitches.