The Rockwell B-1 Lancer[b] is a supersonic variable-sweep wing, heavy bomber used by the United States Air Force. It has been nicknamed the "Bone" (from "B-One"). As of 2024, it is one of the U.S. Air Force's three strategic bomber types, along with the B-2 Spirit and the B-52 Stratofortress.

The B-1 has a blended wing body configuration, with variable-sweep wings, four turbofan engines, triangular ride-control fins and a cruciform tail. The wings can sweep from 15 degrees to 67.5 degrees (full forward to full sweep). Forward-swept wing settings are used for takeoff, landings and high-altitude economical cruise. Aft-swept wing settings are used in high subsonic and supersonic flight. The B-1's variable-sweep wings and thrust-to-weight ratio provide it with improved takeoff performance, allowing it to use shorter runways than previous bombers. The length of the aircraft presented a flexing problem due to air turbulence at low altitude. To alleviate this, Rockwell included small triangular fin control surfaces or vanes near the nose on the B-1. The B-1's Structural Mode Control System moves the vanes, and lower rudder, to counteract the effects of turbulence and smooth out the ride.

B-1b Lancer on full afterburner with fully swept wings