The B-21 Raider is expected to have its first flight in December 2021, according to Air Force Vice Chief of Staff Gen. Stephen Wilson. Speaking at a Mitchell Institute event, Wilson said he has an app on his phone that is "counting down the days . . . And don't hold it to me, but I think it’s something like 863 days until the first flight of the B-21." He said Northrop Grumman, under contract to develop the aircraft, is...