Soviet Union interceptor aircraft, the only effective anti-bomber weapon in the 1950s, were already unable to intercept the high-flying Lockheed U-2; the Valkyrie would fly at similar altitudes, but much higher speeds, and was expected to fly right by the fighters. By the late 1950s, however, anti-aircraft surface-to-air missiles (SAMs) could threaten high-altitude aircraft, as demonstrated by the 1960 downing of Gary Powers' U-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. ==Development== ===Background=== In 1955, the USAF issued requirements for a new bomber combining the payload and range of the Boeing B-52 Stratofortress with the Mach 2 maximum speed of the Convair B-58 Hustler.
In December 1957, the USAF selected North American Aviation's B-70 Valkyrie for this role, a six-engine bomber that could cruise at Mach 3 at high altitude ().
Air Force fleet , the other two being the B-2 Spirit and the B-52 Stratofortress. The B-1 was first envisioned in the 1960s as a platform that would combine the Mach 2 speed of the B-58 Hustler with the range and payload of the B-52, and was meant to ultimately replace both bombers.
Soviet Union interceptor aircraft, the only effective anti-bomber weapon in the 1950s, were already unable to intercept the high-flying Lockheed U-2; the Valkyrie would fly at similar altitudes, but much higher speeds, and was expected to fly right by the fighters. By the late 1950s, however, anti-aircraft surface-to-air missiles (SAMs) could threaten high-altitude aircraft, as demonstrated by the 1960 downing of Gary Powers' U-2.
Plans called for 240 B-1As to be built, with initial operational capability set for 1979. Rockwell's design featured a number of features common to 1960s U.S.
Because of this, and a growing shift to the intercontinental ballistic missile (ICBM) force, the B-70 bomber program was cancelled in 1961 by President John F.
A number of studies on a strategic-range counterpart followed. The first post-B-70 strategic penetrator study was known as the Subsonic Low-Altitude Bomber (SLAB), which was completed in 1961.
This was the first entry in the new bomber designation series, created in 1962.
In August 1963, the similar Low-Altitude Manned Penetrator design was completed, which called for an aircraft with a bomb load and somewhat shorter range of . These all culminated in the October 1963 Advanced Manned Precision Strike System (AMPSS), which led to industry studies at Boeing, General Dynamics, and North American.
McNamara limited the AMSA program to studies and component development beginning in 1964. Program studies continued; IBM and Autonetics were awarded AMSA advanced avionics study contracts in 1968.
McNamara limited the AMSA program to studies and component development beginning in 1964. Program studies continued; IBM and Autonetics were awarded AMSA advanced avionics study contracts in 1968.
He again vetoed funding for AMSA aircraft development in 1968. ===B-1A program=== President Richard Nixon reestablished the AMSA program after taking office, keeping with his administration's flexible response strategy that required a broad range of options short of general nuclear war.
In April 1969, the program officially became the B-1A.
The Air Force issued a request for proposals in November 1969. Proposals were submitted by Boeing, General Dynamics and North American Rockwell in January 1970.
The Air Force issued a request for proposals in November 1969. Proposals were submitted by Boeing, General Dynamics and North American Rockwell in January 1970.
In June 1970, North American Rockwell was awarded the development contract.
In 1970, the estimated unit cost was $40 million, and by 1975, this figure had climbed to $70 million. ===New problems and cancellation=== In 1976, Soviet pilot Viktor Belenko defected to Japan with his MiG-25 "Foxbat".
This was cut in 1971 to one ground and three flight test aircraft.
The fourth B-1A was equipped with a conventional ejection seat for each crew member. The B-1A mockup review occurred in late October 1971; this resulted in 297 requests for alteration to the design due to failures to meet specifications and desired improvements for ease of maintenance and operation.
The company changed its name to Rockwell International and named its aircraft division North American Aircraft Operations in 1973.
74–0158) flew on 23 December 1974.
In 1970, the estimated unit cost was $40 million, and by 1975, this figure had climbed to $70 million. ===New problems and cancellation=== In 1976, Soviet pilot Viktor Belenko defected to Japan with his MiG-25 "Foxbat".
He was informed of the relatively new work on stealth aircraft that had started in 1975, and he decided that this was a better approach than the B-1.
Engine testing also continued during this time with the YF101 engines totaling almost 7,600 hours. ===Shifting priorities=== It was during this period that the Soviets started to assert themselves in several new theaters of action, in particular through Cuban proxies during the Angolan Civil War starting in 1975 and the Soviet invasion of Afghanistan in 1979.
A fourth prototype, built to production standards, was ordered in the fiscal year 1976 budget.
In 1970, the estimated unit cost was $40 million, and by 1975, this figure had climbed to $70 million. ===New problems and cancellation=== In 1976, Soviet pilot Viktor Belenko defected to Japan with his MiG-25 "Foxbat".
During the 1976 federal election campaign, Jimmy Carter made it one of the Democratic Party's platforms, saying "The B-1 bomber is an example of a proposed system which should not be funded and would be wasteful of taxpayers' dollars." When Carter took office in 1977 he ordered a review of the entire program.
This led to the program being canceled in 1977, after the B-1A prototypes had been built. The program was restarted in 1981, largely as an interim measure due to delays in the B-2 stealth bomber program.
During the 1976 federal election campaign, Jimmy Carter made it one of the Democratic Party's platforms, saying "The B-1 bomber is an example of a proposed system which should not be funded and would be wasteful of taxpayers' dollars." When Carter took office in 1977 he ordered a review of the entire program.
A program to improve the B-52 and develop and deploy the ALCM would cost at least 20% less than the planned 244 B-1As. On 30 June 1977, Carter announced that the B-1A would be canceled in favor of ICBMs, SLBMs, and a fleet of modernized B-52s armed with ALCMs.
Carter called it "one of the most difficult decisions that I've made since I've been in office." No mention of the stealth work was made public with the program being top secret, but it is now known that in early 1978 he authorized the Advanced Technology Bomber (ATB) project, which eventually led to the B-2 Spirit. Domestically, the reaction to the cancellation was split along partisan lines.
Plans called for 240 B-1As to be built, with initial operational capability set for 1979. Rockwell's design featured a number of features common to 1960s U.S.
Engine testing also continued during this time with the YF101 engines totaling almost 7,600 hours. ===Shifting priorities=== It was during this period that the Soviets started to assert themselves in several new theaters of action, in particular through Cuban proxies during the Angolan Civil War starting in 1975 and the Soviet invasion of Afghanistan in 1979.
Air Force. During the 1980 presidential campaign, Ronald Reagan campaigned heavily on the platform that Carter was weak on defense, citing the cancellation of the B-1 program as an example, a theme he continued using into the 1980s.
This led to the program being canceled in 1977, after the B-1A prototypes had been built. The program was restarted in 1981, largely as an interim measure due to delays in the B-2 stealth bomber program.
For the price of one bomber, you can have 200 cruise missiles." Flight tests of the four B-1A prototypes for the B-1A program continued through April 1981.
During 1981, funds were allocated to a new study for a bomber for the 1990s time-frame which led to developing the Long-Range Combat Aircraft (LRCA) project.
The LRCA evaluated the B-1, F-111, and ATB as possible solutions; an emphasis was placed on multi-role capabilities, as opposed to purely strategic operations. In 1981, it was believed the B-1 could be in operation before the ATB, covering the transitional period between the B-52's increasing vulnerability and the ATB's introduction.
Reagan decided the best solution was to procure both the B-1 and ATB, and on 2 October 1981 he announced that 100 B-1s were to be ordered to fill the LRCA role. In January 1982, the U.S.
Reagan decided the best solution was to procure both the B-1 and ATB, and on 2 October 1981 he announced that 100 B-1s were to be ordered to fill the LRCA role. In January 1982, the U.S.
The first B-1B was completed and began flight testing in March 1983.
The first production B-1B was rolled out on 4 September 1984 and first flew on 18 October 1984.
Studies suggested that the existing B-52 fleet with ALCM would remain a credible threat until 1985.
After 1985, the introduction of the SA-10 missile, the MiG-31 interceptor and the first effective Soviet Airborne Early Warning and Control (AWACS) systems would make the B-52 increasingly vulnerable.
Deliveries of the B-1B began in 1986 and formally entered service with Strategic Air Command (SAC) as a nuclear bomber that same year.
By 1988, all 100 aircraft had been delivered. With the disestablishment of SAC and its reassignment to the Air Combat Command in 1992, the B-1B was converted for a conventional bombing role.
The 100th and final B-1B was delivered on 2 May 1988; before the last B-1B was delivered, the USAF had determined that the aircraft was vulnerable to Soviet air defenses. ==Design== ===Overview=== The B-1 has a blended wing body configuration, with variable-sweep wing, four turbofan engines, triangular fin control surfaces and cruciform tail.
During 1981, funds were allocated to a new study for a bomber for the 1990s time-frame which led to developing the Long-Range Combat Aircraft (LRCA) project.
By 1988, all 100 aircraft had been delivered. With the disestablishment of SAC and its reassignment to the Air Combat Command in 1992, the B-1B was converted for a conventional bombing role.
In November 1993, three B-1Bs set a long-distance record for the aircraft, which demonstrated its ability to conduct extended mission lengths to strike anywhere in the world and return to base without any stops.
The National Aeronautic Association recognized the B-1B for completing one of the 10 most memorable record flights for 1994. ===Upgrades=== The B-1 has been upgraded since production, beginning with the "Conventional Mission Upgrade Program" (CMUP), which added a new MIL-STD-1760 smart-weapons interface to enable the use of precision-guided conventional weapons.
The B-1B Block D upgrade added a Global Positioning System (GPS) receiver beginning in 1995. The B-1's defensive electronics include the Eaton AN/ALQ-161A radar warning and defensive jamming equipment, which has three sets of antennas; one at the front base of each wing and the third rear-facing in the tail radome.
It first served in combat during Operation Desert Fox in 1998 and again during the NATO action in Kosovo the following year.
Upgrades were completed in September 2006. Block F was the Defensive Systems Upgrade Program (DSUP) to improve the aircraft's electronic countermeasures and jamming capabilities, but it was canceled in December 2002 due to cost overruns and delays. In 2007, the Sniper XR targeting pod was integrated on the B-1 fleet.
Upgrades were completed in September 2006. Block F was the Defensive Systems Upgrade Program (DSUP) to improve the aircraft's electronic countermeasures and jamming capabilities, but it was canceled in December 2002 due to cost overruns and delays. In 2007, the Sniper XR targeting pod was integrated on the B-1 fleet.
Upgrades were completed in September 2006. Block F was the Defensive Systems Upgrade Program (DSUP) to improve the aircraft's electronic countermeasures and jamming capabilities, but it was canceled in December 2002 due to cost overruns and delays. In 2007, the Sniper XR targeting pod was integrated on the B-1 fleet.
Following accelerated testing, the Sniper pod was fielded in summer 2008.
Future precision munitions include the Small Diameter Bomb. The USAF commenced the Integrated Battle Station (IBS) modification in 2012 as a combination of three separate upgrades when it realised the benefits of completing them concurrently; the Fully Integrated Data Link (FIDL), Vertical Situational Display Unit (ASDU) and Central Integrated Test System (CITS).
The Air Force had 62 B-1Bs in service as of 2016.
The IBS upgrades were completed in 2020. In August 2019, the Air Force unveiled a modification to the B-1B to allow it to carry more weapons internally and externally.
The IBS upgrades were completed in 2020. In August 2019, the Air Force unveiled a modification to the B-1B to allow it to carry more weapons internally and externally.
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