Rockwell's B-1 Lancer, a supersonic variable-sweep wing, heavy bomber used by the United States Air Force had its first flight on 23 December 1974, 48 years ago. The Bone (from "B-One") entered service with USAF on 1 October 1974 and is one of three strategic bombers serving in the U.S. Air Force fleet along with the B-2 Spirit and the B-52 Stratofortress as of 2022.
The B-1 was intended as a platform that would combine the Mach 2 speed of the B-58 Hustler with the range and payload of the B-52. It was meant to ultimately replace both in service. As it is, it will probably be outlived by the B52 that went into service with the USAF in 1955 and is set for retirement in 2050.
Rockwell International (now part of Boeing) with its B-1A that had a planned top speed of Mach 2.2 at high altitude and the capability of flying for long distances at Mach 0.85 at very low altitudes won the design contest.
Four B-1A prototypes were built but then because of the high cost and the introduction of the AGM-86 cruise missile that flew the same basic speed and distance led to the program being cancelled in 1977.
Four years later the program was restarted as the B1B Lancers, a much improved and modernised aircraft having a lower top speed of Mach 1.25 at high altitude, but an improved low-altitude speed to Mach 0.96. The airframe was improved to allow take-off with the maximum possible fuel and weapons load.
First deliveries of the B-1B to the USAF Strategic Air Command (SAC) as a nuclear bomber began in 1985. Initial operational capability was reached on 1 October 1986 and the B-1B was placed on nuclear alert status. By 1988, all 100 aircraft that had been ordered were delivered.
In late 1990, engine fires in two Lancers led to a grounding of the fleet and the aircraft were placed on "limited alert"; in other words, they were grounded unless a nuclear war broke out. Following inspections and repairs they were returned to duty beginning on 6 February 1991.
In 1992 the SAC ceased to operate and its fleet of B1B's were re-assigned to the USAF Air Combat Command. The ex-SAC B-1B's Lancers were then converted for service in the conventional bombing role with forty of them able to drop the 500-pound (230 kg) Mk-82 General Purpose (GP) bomb.
Despite being cleared for this role, the problems with the engines prevented their use in Operation Desert Storm during the Gulf War. However, Lancers saw operational service in 1998 during Operation Desert Fox and in Kosovo in 1999. Lancers has also seen extensive service in support of US and UN forces in Afghanistan and Iraq. In 2003 in the first six months of Operation Enduring Freedom, eight B-1s dropped almost 40 percent of aerial ordnance, including some 3,900 JDAMs. JDAM munitions were heavily used by the B-1 over Iraq. During Operation Enduring Freedom, the B-1 was able to raise its mission capable rate to 79%.
Of the 100 B-1Bs built, 93 remained in 2000 after losses in accidents. In June 2001, the Pentagon sought to place one-third of its then fleet into storage. The proposal was intended to allow money to be diverted to further upgrades to the remaining B-1Bs. In 2003 the USAF decided to retire 33 aircraft to concentrate its budget on maintaining availability of the remaining B-1Bs. However, in 2004 seven mothballed bombers returned to service to increase the fleet to 67 aircraft.
In August 2012, the 9th Expeditionary Bomb Squadron returned from a six-month tour in Afghanistan where they had accounted for a quarter of all combat aircraft sorties over the country. The Squadron spent 9,500 hours airborne flying 770 sorties, the most of any B-1B squadron on a single deployment.
Beginning in 2014, the B-1 saw action when it was used against the Islamic State (IS) in the Syrian Civil War. From August 2014 to January 2015, the B-1 accounted for eight percent of USAF sorties during Operation Inherent Resolve.
As of 2021 the USAF had an inventory of 45 B-1Bs 2. The Northrop Grumman B-21 Raider is to begin replacing the B-1B after 2025; all B-1s are planned to be retired by 2036.