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 ().
Soviet Union interceptor aircraft, the only effective anti-bomber weapon in the 1950s, the Valkyrie would fly at similar altitudes, but much higher speeds, and was expected to fly right by the fighters. as demonstrated by the
1960 downing of
Gary Powers' U-2. The USAF
Strategic Air Command (SAC) was aware of these developments and had begun moving its bombers to low-level penetration even before the U-2 incident. This tactic greatly reduces radar detection distances through the use of
terrain masking; using features of the terrain like hills and valleys, the line-of-sight from the radar to the bomber can be broken, rendering the radar (and human observers) incapable of seeing it. and the two XB-70 prototypes were used in a supersonic research program. Although never intended for the low-level role, the B-52's flexibility allowed it to outlast its intended successor as the nature of the air war environment changed. The B-52's huge fuel load allowed it to operate at lower altitudes for longer times, and its large airframe allowed the addition of improved
radar jamming and deception suites to deal with radars. During the
Vietnam War, the concept that all future wars would be nuclear was turned on its head, and the "big belly" modifications increased the B-52's total bomb load to , turning it into a powerful tactical aircraft which could be used against ground troops along with strategic targets from high altitudes. 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 produced a design that looked more like an airliner than a bomber, with a large, swept wing,
T-tail, and large
high-bypass engines. This was followed by the similar Extended Range Strike Aircraft (ERSA), which added a
variable-sweep wing, then en vogue in the aviation industry. ERSA envisioned a relatively small aircraft with a payload and a range of including flown at low altitudes. 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 (later
North American Rockwell). In mid-1964, the USAF had revised its requirements and retitled the project as Advanced Manned Strategic Aircraft (AMSA), which differed from AMPSS primarily in that it also demanded a high-speed high-altitude capability, similar to that of the existing Mach 2-class F-111. Given the lengthy series of design studies, North American Rockwell engineers joked that the new name, AMSA actually stood for "America's Most Studied Aircraft". The arguments that led to the cancellation of the B-70 program caused some to question the need for a new strategic bomber of any sort. The USAF was adamant about retaining bombers as part of the
nuclear triad concept that included bombers, ICBMs, and
submarine-launched ballistic missiles (SLBMs) in a combined package that complicated any potential defense. They argued that the bomber was needed to attack hardened military targets and to provide a safe
counterforce option because the bombers could be quickly launched into safe loitering areas where they could not be attacked. However, the introduction of the SLBM made moot the mobility and survivability argument, and a newer generation of ICBMs, such as the
Minuteman III, had the accuracy and speed needed to attack point targets. During this time, ICBMs were seen as a less costly option based on their lower unit cost, but development costs were much higher. and felt a new expensive bomber was not needed. Program studies continued;
IBM and
Autonetics were awarded AMSA advanced avionics study contracts in 1968.
B-1A program radar for the B-1A 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. Nixon's Secretary of Defense,
Melvin Laird, reviewed the programs and decided to lower the numbers of FB-111s, since they lacked the desired range, and recommended that the AMSA design studies be accelerated. In June 1970, North American Rockwell was awarded the development contract. The original program called for two test airframes, five flyable aircraft, and 40 engines. This was cut in 1971 to one ground and three flight test aircraft. The company changed its name to
Rockwell International and named its aircraft division North American Aircraft Operations in 1973. A fourth prototype, built to production standards, was ordered in the fiscal year 1976 budget. Plans called for 240 B-1As to be built, with
initial operational capability set for 1979. Rockwell's design had features common to the F-111 and XB-70. It used a
crew escape capsule, that ejected as a unit to improve crew survivability if the crew had to abandon the aircraft at high speed. Additionally, the design featured large variable-sweep wings in order to provide both more
lift during takeoff and landing, and lower drag during a high-speed dash phase. Initially, it had been expected that a Mach 1.2 performance could be achieved at low altitude, which required that titanium be used in critical areas in the fuselage and wing structure. The low altitude performance requirement was later lowered to Mach 0.85, reducing the amount of titanium and therefore cost. The first three B-1As featured the escape capsule that ejected the cockpit with all four crew members inside. 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 first B-1A prototype (Air Force serial no. 74-0158) flew on 23 December 1974. As the program continued the per-unit cost continued to rise in part because of high
inflation during that period. In 1970, the estimated unit cost was $40 million, and by 1975, this figure had climbed to $70 million.
New problems and cancellation underside in 1981 |alt= A B-1A flying with its wings swept forward, showing its anti-flash white underside In 1976, Soviet pilot
Viktor Belenko defected to
Japan with his
MiG-25 "Foxbat". During debriefing he described a new "super-Foxbat" (almost certainly referring to the
MiG-31) that had look-down/shoot-down
radar in order to attack cruise missiles. This would also make any low-level penetration aircraft "visible" and easy to attack. Given that the B-1's armament suite was similar to the B-52, and it then appeared no more likely to survive Soviet airspace than the B-52, the program was increasingly questioned. In particular, Senator
William Proxmire continually derided the B-1 in public, arguing it was an outlandishly expensive dinosaur. 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. By this point the projected cost of the program had risen to over $100 million per aircraft, although this was lifetime cost over 20 years. 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.
Pentagon officials also stated that the
AGM-86 Air-Launched Cruise Missile (ALCM) launched from the existing B-52 fleet would give the USAF equal capability of penetrating Soviet airspace. With a range of , the ALCM could be launched well outside the range of any Soviet defenses and penetrate at low altitude like a bomber (with a much lower
radar cross-section (RCS) due to smaller size), and in much greater numbers at a lower cost. A small number of B-52s could launch hundreds of ALCMs, saturating the defense. 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. Domestically, the reaction to the cancellation was split along partisan lines. The Department of Defense was surprised by the announcement; it expected that the number of B-1s ordered would be reduced to around 150. Congressman
Robert Dornan (R-CA) claimed, "They're breaking out the vodka and caviar in Moscow." However, it appears the Soviets were more concerned by large numbers of ALCMs representing a much greater threat than a smaller number of B-1s. Soviet news agency
TASS commented that "the implementation of these militaristic plans has seriously complicated efforts for the limitation of the strategic arms race."
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. U.S. strategy to this point had been focused on
containing Communism and preparation for war in Europe. The new Soviet actions revealed that the military lacked capability outside these narrow confines. The U.S. Department of Defense responded by accelerating its
Rapid Deployment Forces concept but suffered from major problems with airlift and sealift capability. 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. During this time Carter's defense secretary,
Harold Brown, announced the stealth bomber project, apparently implying that this was the reason for the B-1 cancellation.
B-1B program , 1984.|alt= The first B-1B at its roll-out ceremony outside a hangar in Palmdale, California in 1984 On taking office, Reagan was faced with the same decision as Carter before: whether to continue with the B-1 for the short term, or to wait for the development of the ATB, a much more advanced aircraft. Studies suggested that the existing B-52 fleet with ALCM would remain a credible threat until 1985. It was predicted that 75% of the B-52 force would survive to attack its targets. 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. 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 January 1982, the U.S. Air Force awarded two contracts to Rockwell worth a combined $2.2 billion for the development and production of 100 new B-1 bombers. Numerous changes were made to the design to make it better suited to the now expected missions, resulting in the
B-1B. High subsonic speeds at low altitude became a focus area for the revised design, To deal with the introduction of the
MiG-31 equipped with the new
Zaslon radar system, and other aircraft with look-down capability, the B-1B's
electronic warfare suite was significantly upgraded. In particular it seemed the B-52 fitted with electronics similar to the B-1B would be equally able to avoid interception, as the speed advantage of the B-1 was now minimal. It also appeared that the "interim" time frame served by the B-1B would be less than a decade, being rendered obsolete shortly after the introduction of a much more capable ATB design. The primary argument in favor of the B-1 was its large
conventional weapon payload, and that its takeoff performance allowed it to operate with a credible bomb load from a much wider variety of airfields. Production subcontracts were spread across many congressional districts, making the aircraft more popular on
Capitol Hill. B-1A No. 1 was disassembled and used for radar testing at the
Rome Air Development Center in the former
Griffiss Air Force Base,
New York. B-1As No. 2 and No. 4 were then modified to include B-1B systems. 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. 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. In 1996, Rockwell International sold most of its space and defense operations to Boeing, which continues as the primary contractor for the B1 as of 2024. ==Design==