Also during 1994, the Air Force selected Ellsworth as the exclusive location from which to conduct a Congressionally mandated operational readiness assessment of the B-1B, known locally as "Dakota Challenge." After six months of hard work, under both peacetime and simulated wartime conditions, the 28 BW and Ellsworth, relying on extensive personnel, technical and logistical support from sister B-1 units at McConnell, Grand Forks and Dyess Air Force Bases, passed the test "with flying colors"; and proved the B-1 to be a reliable and capable weapons system; the mainstay of America's heavy bomber fleet for years to come.