The B1 bomber, officially known as the Rockwell B-1 Lancer, is a supersonic strategic bomber used by the United States Air Force. Designed for long-range missions, it can carry both conventional and nuclear weapons. The B1 features a variable-sweep wing design, allowing it to adapt its shape for different flight speeds and missions. First introduced in the 1980s, the B1 bomber has undergone several upgrades to enhance its capabilities. It is known for its speed, range, and ability to evade radar detection, making it a key component of the U.S. military's strategic bombing forces.