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The Rockwell B-1 Lancer is a supersonic
variable-sweep wing A variable-sweep wing, colloquially known as a "swing wing", is an airplane wing, or set of wings, that may be swept back and then returned to its original straight position during flight. It allows the aircraft's shape to be modified in fli ...
,
heavy bomber Heavy bombers are bomber aircraft capable of delivering the largest payload of air-to-ground weaponry (usually bombs) and longest range ( takeoff to landing) of their era. Archetypal heavy bombers have therefore usually been among the larg ...
used by the
United States Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Si ...
. It is commonly called the "Bone" (from "B-One"). It is one of three
strategic bomber A strategic bomber is a medium- to long-range Penetrator (aircraft), penetration bomber aircraft designed to drop large amounts of air-to-ground weaponry onto a distant target for the purposes of debilitating the enemy's capacity to wage war. Unl ...
s serving in the U.S. Air Force fleet along with the
B-2 Spirit The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American heavy strategic bomber, featuring low-observable stealth technology designed to penetrate dense anti-aircraft defenses. A subsonic flying w ...
and the
B-52 Stratofortress The Boeing B-52 Stratofortress is an American long-range, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing, which has continued to provide support and upgrades. It has been operated by the United States Air ...
. The B-1 was first envisioned in the 1960s as a platform that would combine the Mach 2 speed of the
B-58 Hustler The Convair B-58 Hustler, designed and produced by American aircraft manufacturer Convair, was the first operational bomber capable of Mach 2 flight. The B-58 was developed during the 1950s for the United States Air Force (USAF) Strategic Air ...
with the range and payload of the B-52, and was meant to ultimately replace both bombers. After a long series of studies,
Rockwell International Rockwell International was a major American manufacturing conglomerate involved in aircraft, the space industry, defense and commercial electronics, components in the automotive industry, printing presses, avionics and industrial products. R ...
(now part of
Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...
) won the design contest for what emerged as the B-1A. This version had a top speed of Mach 2.2 at high altitude and the ability to fly for long distances at Mach 0.85 at very low altitudes. The combination of the high cost of the aircraft, the introduction of the
AGM-86 The AGM-86 ALCM is an American subsonic air-launched cruise missile (ALCM) built by Boeing and operated by the United States Air Force. This missile was developed to increase the effectiveness and survivability of the Boeing B-52H Stratofortres ...
cruise missile A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warh ...
that flew the same basic speed and distance, and early work on the B-2 stealth bomber reduced the need for the B-1. The program was 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 Stealth aircraft are designed to avoid detection using a variety of technologies that reduce reflection/emission of radar, infrared, visible light, radio frequency (RF) spectrum, and audio, collectively known as stealth technology. The F-117 Nig ...
program. The B-1A design was altered, reducing top speed to Mach 1.25 at high
altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...
, increasing low-altitude speed to Mach 0.96, extensively improving electronic components, and upgrading the airframe to carry more fuel and weapons. Dubbed the B-1B, deliveries of the new variant began in 1986; the plane formally entered service with
Strategic Air Command Strategic Air Command (SAC) was both a United States Department of Defense Specified Command and a United States Air Force (USAF) Major Command responsible for command and control of the strategic bomber and intercontinental ballistic missile ...
(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 Air Combat Command (ACC) is one of nine Major Commands (MAJCOMs) in the United States Air Force, reporting to Headquarters, United States Air Force (HAF) at the Pentagon. It is the primary provider of air combat forces for the Air Force, and i ...
in 1992, the B-1B was converted for a conventional bombing role. It first served in combat during
Operation Desert Fox The 1998 bombing of Iraq (code-named Operation Desert Fox) was a major four-day bombing campaign on Iraqi targets from 16 to 19 December 1998, by the United States and the United Kingdom. On 16 December 1998, President of the United States Bill ...
in 1998 and again during the NATO action in Kosovo the following year. The B-1B has supported U.S. and
NATO The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two N ...
military forces in
Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is borde ...
and
Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
. As of 2021 the Air Force has 45 B-1Bs. The
Northrop Grumman B-21 Raider The Northrop Grumman B-21 Raider is an American strategic bomber under development for the United States Air Force (USAF) by Northrop Grumman. As part of the Long Range Strike Bomber (LRS-B) program, it is to be a long-range, stealth intercon ...
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 The Boeing B-52 Stratofortress is an American long-range, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing, which has continued to provide support and upgrades. It has been operated by the United States Air ...
with the Mach 2 maximum speed of the
Convair B-58 Hustler The Convair B-58 Hustler, designed and produced by American aircraft manufacturer Convair, was the first operational bomber capable of Mach 2 flight. The B-58 was developed during the 1950s for the United States Air Force (USAF) Strategic Air ...
.Jenkins 1999, p. 10. In December 1957, the USAF selected
North American Aviation North American Aviation (NAA) was a major American aerospace manufacturer that designed and built several notable aircraft and spacecraft. Its products included: the T-6 Texan trainer, the P-51 Mustang fighter, the B-25 Mitchell bomber, the ...
's B-70 Valkyrie for this role, a six-engine bomber that could cruise at Mach 3 at high altitude ().
Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...
interceptor aircraft An interceptor aircraft, or simply interceptor, is a type of fighter aircraft designed specifically for the defensive interception role against an attacking enemy aircraft, particularly bombers and reconnaissance aircraft. Aircraft that are ...
, the only effective anti-bomber weapon in the 1950s, were already unable to intercept the high-flying
Lockheed U-2 The Lockheed U-2, nicknamed "''Dragon Lady''", is an American single- jet engine, high altitude reconnaissance aircraft operated by the United States Air Force (USAF) and previously flown by the Central Intelligence Agency (CIA). It provides d ...
; 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 missile A surface-to-air missile (SAM), also known as a ground-to-air missile (GTAM) or surface-to-air guided weapon (SAGW), is a missile designed to be launched from the ground to destroy aircraft or other missiles. It is one type of anti-aircraft syst ...
s (SAMs) could threaten high-altitude aircraft, as demonstrated by the 1960 downing of
Gary Powers Francis Gary Powers (August 17, 1929 – August 1, 1977) was an American pilot whose Central Intelligence Agency (CIA) Lockheed U-2 spy plane was shot down while flying a reconnaissance mission in Soviet Union airspace, causing the 1960 U-2 i ...
' U-2. The USAF
Strategic Air Command Strategic Air Command (SAC) was both a United States Department of Defense Specified Command and a United States Air Force (USAF) Major Command responsible for command and control of the strategic bomber and intercontinental ballistic missile ...
(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 Nap-of-the-earth (NOE) is a type of very low-altitude flight course used by military aircraft to avoid enemy detection and attack in a high-threat environment. Other, mostly older terms include "ground-hugging", "terrain masking", "flying under t ...
; 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. Additionally, radars of the era were subject to "
clutter Clutter and its derivations may refer to any of the following: Excessive physical disorder * Clutter, a confusing, or disorderly, state or collection, and possible symptom of compulsive hoarding * Clutter (marketing), numerous advertisements, a ...
" from stray returns from the ground and other objects, which meant a minimum angle existed above the horizon where they could detect a target. Bombers flying at low altitudes could remain under these angles simply by keeping their distance from the radar sites. This combination of effects made SAMs of the era ineffective against low-flying aircraft. The same effects also meant that low-flying aircraft were difficult to detect by higher-flying interceptors, since their radar systems could not readily pick out aircraft against the clutter from ground reflections (lack of
look-down/shoot-down A radar system has look-down/shoot-down capability if it can detect, track and guide a weapon to an air target that (as seen by the radar) is silhouetted against the ground. Problem and naming Airborne intercept radar relying exclusively on time ...
capability). The switch from high-altitude to low-altitude flight profiles severely affected the B-70, the design of which was tuned for high-altitude performance. Higher
aerodynamic drag In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding ...
at low level limited the B-70 to subsonic speed while dramatically decreasing its range. The result would be an aircraft with somewhat higher subsonic speed than the B-52, but less range. Because of this, and a growing shift to the
intercontinental ballistic missile An intercontinental ballistic missile (ICBM) is a ballistic missile with a range greater than , primarily designed for nuclear weapons delivery (delivering one or more thermonuclear warheads). Conventional, chemical, and biological weapo ...
(ICBM) force, the B-70 bomber program was cancelled in 1961 by President John F. Kennedy, 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 the large airframe allowed the addition of improved
radar jamming and deception Radar jamming and deception is a form of electronic countermeasures that intentionally sends out radio frequency signals to interfere with the operation of radar by saturating its receiver with noise or false information. Concepts that blanket the ...
suites to deal with radars. During the
Vietnam War The Vietnam War (also known by #Names, other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vie ...
, 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. The much smaller bomb bay of the B-70 would have made it much less useful in this role.


Design studies and delays

Although effective, the B-52 was not ideal for the low-level role. This led to a number of aircraft designs known as penetrators, which were tuned specifically for long-range low-altitude flight. The first of these designs to see operation was the supersonic
F-111 The General Dynamics F-111 Aardvark is a retired supersonic, medium-range, multirole combat aircraft. Production variants of the F-111 had roles that included ground attack (e.g. interdiction), strategic bombing (including nuclear weapons ca ...
fighter-bomber, which used variable-sweep wings for tactical missions. 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 A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane is ...
, and large high-bypass engines. This was followed by the similar Extended Range Strike Aircraft (ERSA), which added a
variable-sweep wing A variable-sweep wing, colloquially known as a "swing wing", is an airplane wing, or set of wings, that may be swept back and then returned to its original straight position during flight. It allows the aircraft's shape to be modified in fli ...
, 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 The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and ...
,
General Dynamics General Dynamics Corporation (GD) is an American publicly traded, aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth-largest defense contractor in the world by arms sales, and 5th largest in the Uni ...
, and
North American North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the ...
. 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, Rockwell engineers joked that the new name actually stood for "America's Most Studied Aircraft". The arguments that led to the cancellation of the B-70 program had led 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 A nuclear triad is a three-pronged military force structure that consists of land-launched nuclear missiles, nuclear-missile-armed submarines, and strategic aircraft with nuclear bombs and missiles. Specifically, these components are land-based ...
concept that included bombers, ICBMs, and
submarine-launched ballistic missile A submarine-launched ballistic missile (SLBM) is a ballistic missile capable of being launched from submarines. Modern variants usually deliver multiple independently targetable reentry vehicles (MIRVs), each of which carries a nuclear warhead ...
s (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 In nuclear strategy, a counterforce target is one that has a military value, such as a launch silo for intercontinental ballistic missiles, an airbase at which nuclear-armed bombers are stationed, a homeport for ballistic missile submarines, or ...
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.
Secretary of Defense A defence minister or minister of defence is a cabinet official position in charge of a ministry of defense, which regulates the armed forces in sovereign states. The role of a defence minister varies considerably from country to country; in so ...
Robert McNamara Robert Strange McNamara (; June 9, 1916 – July 6, 2009) was an American business executive and the eighth United States Secretary of Defense, serving from 1961 to 1968 under Presidents John F. Kennedy and Lyndon B. Johnson. He remains the ...
preferred ICBMs over bombers for the Air Force portion of the deterrent force and felt a new expensive bomber was not needed."B-1A page."
''fas.org''. Retrieved: 20 March 2008.
McNamara limited the AMSA program to studies and component development beginning in 1964. Program studies continued; IBM and
Autonetics Autonetics was a division of North American Aviation that produced various avionics but is best known for their inertial navigation systems used in submarines and intercontinental ballistic missiles. Its 188-acre facility in Anaheim, California, ...
were awarded AMSA advanced avionics study contracts in 1968. McNamara remained opposed to the program in favor of upgrading the existing B-52 fleet and adding nearly 300 FB-111s for shorter range roles then being filled by the B-58.Schwartz 1998, p. 119. He again vetoed funding for AMSA aircraft development in 1968.


B-1A program

President
Richard Nixon Richard Milhous Nixon (January 9, 1913April 22, 1994) was the 37th president of the United States, serving from 1969 to 1974. A member of the Republican Party, he previously served as a representative and senator from California and was ...
reestablished the AMSA program after taking office, keeping with his administration's
flexible response Flexible response was a defense strategy implemented by John F. Kennedy in 1961 to address the Kennedy administration's skepticism of Dwight Eisenhower's New Look and its policy of massive retaliation. Flexible response calls for mutual deterre ...
strategy that required a broad range of options short of general nuclear war. Nixon's Secretary of Defense,
Melvin Laird Melvin Robert Laird Jr. (September 1, 1922 – November 16, 2016) was an American politician, writer and statesman. He was a U.S. congressman from Wisconsin from 1953 to 1969 before serving as Secretary of Defense from 1969 to 1973 under Pres ...
, 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 April 1969, the program officially became the ''B-1A''. This was the first entry in the new bomber designation series, created in 1962. 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. 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 Rockwell International was a major American manufacturing conglomerate involved in aircraft, the space industry, defense and commercial electronics, components in the automotive industry, printing presses, avionics and industrial products. R ...
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 Initial operating capability or initial operational capability (IOC) is the state achieved when a capability is available in its minimum usefully deployable form. The term is often used in government or military procurement. The United States D ...
set for 1979. Rockwell's design had features common to the
General Dynamics F-111 Aardvark The General Dynamics F-111 Aardvark is a retired supersonic, medium-range, multirole combat aircraft. Production variants of the F-111 had roles that included ground attack (e.g. interdiction), strategic bombing (including nuclear weapons c ...
and
North American XB-70 Valkyrie The North American Aviation XB-70 Valkyrie was the prototype version of the planned B-70 nuclear-armed, deep-penetration supersonic strategic bomber for the United States Air Force Strategic Air Command. Designed in the late 1950s by North Ame ...
. 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 Lift or LIFT may refer to: Physical devices * Elevator, or lift, a device used for raising and lowering people or goods ** Paternoster lift, a type of lift using a continuous chain of cars which do not stop ** Patient lift, or Hoyer lift, mobil ...
during takeoff and landing, and lower drag during a high-speed dash phase. With the wings set to their widest position the aircraft had a much better airfield performance than the B-52, allowing it to operate from a wider variety of bases. Penetration of the Soviet Union's defenses would take place at
supersonic speed Supersonic speed is the speed of an object that exceeds the speed of sound ( Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately . Speeds greater than five times ...
, crossing them as quickly as possible before entering the more sparsely defended interior of the country where speeds could be reduced again. The large size and fuel capacity of the design would allow the "dash" portion of the flight to be relatively long. In order to achieve the required Mach 2 performance at high altitudes, the exhaust nozzles and air
intake ramp An intake ramp is a rectangular, plate-like device within the air intake of a jet engine, designed to generate a number of shock waves to aid the inlet compression process at supersonic speeds. The ramp sits at an acute angle to deflect the intake ...
s were variable. 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. A pair of small vanes mounted near the nose are part of an active vibration damping system that smooths out the otherwise bumpy low-altitude ride. 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 In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rock ...
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 In economics, inflation is an increase in the general price level of goods and services in an economy. When the general price level rises, each unit of currency buys fewer goods and services; consequently, inflation corresponds to a reduct ...
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

In 1976, Soviet pilot
Viktor Belenko Viktor Ivanovich Belenko (russian: Виктор Иванович Беленко, born 15 February 1947) is a Russian-born American aerospace engineer and former Soviet pilot who defected in 1976 to the West while flying his MiG-25 jet intercep ...
defected to
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...
with his MiG-25 "Foxbat". During debriefing he described a new "super-Foxbat" (almost certainly referring to the
MiG-31 The Mikoyan MiG-31 (russian: link=no, Микоян МиГ-31; NATO reporting name: Foxhound) is a supersonic interceptor aircraft that was developed for use by the Soviet Air Forces. The aircraft was designed by the Mikoyan design bureau as a ...
) that had look-down/shoot-down
radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...
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 now appeared no more likely to survive Soviet airspace than the B-52, the program was increasingly questioned. In particular, Senator
William Proxmire Edward William Proxmire (November 11, 1915 – December 15, 2005) was an American politician. A member of the Democratic Party, he served as a United States Senator from Wisconsin from 1957 to 1989. He holds the record for being the longest-serv ...
continually derided the B-1 in public, arguing it was an outlandishly expensive dinosaur. During the 1976 federal election campaign,
Jimmy Carter James Earl Carter Jr. (born October 1, 1924) is an American politician who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party (United States), Democratic Party, he previously served as th ...
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.""Carter's Big Decision: Down Goes the B-1, Here Comes the Cruise."
''Time'', 11 July 1977. Retrieved: 8 October 2009.
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 Stealth aircraft are designed to avoid detection using a variety of technologies that reduce reflection/emission of radar, infrared, visible light, radio frequency (RF) spectrum, and audio, collectively known as stealth technology. The F-117 ...
that had started in 1975, and he decided that this was a better approach than the B-1.
Pentagon In geometry, a pentagon (from the Greek πέντε ''pente'' meaning ''five'' and γωνία ''gonia'' meaning ''angle'') is any five-sided polygon or 5-gon. The sum of the internal angles in a simple pentagon is 540°. A pentagon may be sim ...
officials also stated that the
AGM-86 The AGM-86 ALCM is an American subsonic air-launched cruise missile (ALCM) built by Boeing and operated by the United States Air Force. This missile was developed to increase the effectiveness and survivability of the Boeing B-52H Stratofortres ...
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 Radar cross-section (RCS), also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. An object reflects a limited amount of radar energy back to the source. ...
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. 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 Classified information is material that a government body deems to be sensitive information that must be protected. Access is restricted by law or regulation to particular groups of people with the necessary security clearance and need to kn ...
, 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 The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American heavy strategic bomber, featuring low-observable stealth technology designed to penetrate dense anti-aircraft defenses. A subsonic flying w ...
. 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 The Russian News Agency TASS (russian: Информацио́нное аге́нтство Росси́и ТАСС, translit=Informatsionnoye agentstvo Rossii, or Information agency of Russia), abbreviated TASS (russian: ТАСС, label=none) ...
commented that "the implementation of these militaristic plans has seriously complicated efforts for the limitation of the strategic arms race." Western military leaders were generally happy with the decision. NATO commander
Alexander Haig Alexander Meigs Haig Jr. (; December 2, 1924February 20, 2010) was United States Secretary of State under President Ronald Reagan and White House Chief of Staff under Presidents Richard Nixon and Gerald Ford. Prior to and in between these ...
described the ALCM as an "attractive alternative" to the B-1. French General Georges Buis stated "The B-1 is a formidable weapon, but not terribly useful. 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. The program included 70 flights totaling 378 hours. A top speed of Mach 2.22 was reached by the second B-1A. 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 The Angolan Civil War ( pt, Guerra Civil Angolana) was a civil war in Angola, beginning in 1975 and continuing, with interludes, until 2002. The war immediately began after Angola became independent from Portugal in November 1975. The war was ...
starting in 1975 and the
Soviet invasion of Afghanistan The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...
in 1979. U.S. strategy to this point had been focused on containing
Communism Communism (from Latin la, communis, lit=common, universal, label=none) is a far-left sociopolitical, philosophical, and economic ideology and current within the socialist movement whose goal is the establishment of a communist society, ...
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. In order to slow an enemy invasion of other countries, air power was critical; however the key Iran-Afghanistan border was outside the range of the
U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage o ...
's carrier-based attack aircraft, leaving this role to the U.S. Air Force. During the 1980 presidential campaign,
Ronald Reagan Ronald Wilson Reagan ( ; February 6, 1911June 5, 2004) was an American politician, actor, and union leader who served as the 40th president of the United States from 1981 to 1989. He also served as the 33rd governor of California from 1967 ...
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

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.Mitchell, Douglas D
"IB81107, "Bomber Options for Replacing B-52s."
''Library of Congress Congressional Research Service, via Digital Library, UNT,'' 3 May 1982. Retrieved: 16 July 2011.
After 1985, the introduction of the
SA-10 The S-300 (NATO reporting name SA-10 Grumble) is a series of long range surface-to-air missile systems developed and operated by the former Soviet Union, now fielded by the militaries of Russia and Ukraine as well as several other former Easte ...
missile, the MiG-31 interceptor and the first effective Soviet
Airborne Early Warning and Control Airborne or Airborn may refer to: Arts, entertainment, and media Films * ''Airborne'' (1962 film), a 1962 American film directed by James Landis * ''Airborne'' (1993 film), a comedy–drama film * ''Airborne'' (1998 film), an action film sta ...
(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 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.Coates, James
"Reagan approves B-1, alters basing for MX."
''Chicago Tribune'', 3 October 1981. Retrieved: 28 July 2010.
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''. These changes included a reduction in maximum speed, which allowed the variable-aspect intake ramps to be replaced by simpler fixed geometry intake ramps. This reduced the B-1B's radar cross-section which was seen as a good trade off for the speed decrease. High subsonic speeds at low altitude became a focus area for the revised design, and low-level speeds were increased from about Mach 0.85 to 0.92. The B-1B has a maximum speed of Mach 1.25 at higher altitudes. The B-1B's maximum takeoff weight was increased to from the B-1A's . The weight increase was to allow for takeoff with a full internal fuel load and for external weapons to be carried. Rockwell engineers were able to reinforce critical areas and lighten non-critical areas of the airframe, so the increase in
empty weight The empty weight of a vehicle is based on its weight without any payload (cargo, passengers, usable fuel, etc.). Aviation Many different empty weight definitions exist. Here are some of the more common ones used. GAMA standardization In 1975 ...
was minimal. To deal with the introduction of the
MiG-31 The Mikoyan MiG-31 (russian: link=no, Микоян МиГ-31; NATO reporting name: Foxhound) is a supersonic interceptor aircraft that was developed for use by the Soviet Air Forces. The aircraft was designed by the Mikoyan design bureau as a ...
equipped with the new
Zaslon The Russian (former USSR) BRLS-8B "Zaslon" (Barrier) is an all-weather multimode airborne radar developed between 1975 and 1980 by the Tikhomirov Scientific Research Institute of Instrument Design as part of the weapons control system of the MiG- ...
radar system, and other aircraft with look-down capability, the B-1B's
electronic warfare Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum (EM spectrum) or directed energy to control the spectrum, attack an enemy, or impede enemy assaults. The purpose of electronic warfare is to deny the opponent ...
suite was significantly upgraded. Opposition to the plan was widespread within Congress. Critics pointed out that many of the original problems remained in both areas of performance and expense. 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 The terms conventional weapons or conventional arms generally refer to weapons whose ability to damage comes from kinetic, incendiary, or explosive energy and exclude weapons of mass destruction (''e.g.'' nuclear, biological, radiological and ...
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 Capitol Hill, in addition to being a metonym for the United States Congress, is the largest historic residential neighborhood in Washington, D.C., stretching easterly in front of the United States Capitol along wide avenues. It is one of the ...
. B-1A No. 1 was disassembled and used for radar testing at the
Rome Air Development Center Rome Laboratory (Rome Air Development Center until 1991) is the US "Air Force 'superlab' for command, control, and communications" research and development and is responsible for planning and executing the USAF science and technology program. ...
at the former
Griffiss Air Force Base Griffiss Air Force Base is a former United States Air Force installation in the northeastern United States, located in Central New York state at Rome, about northwest of Utica. Missions included fighter interceptors, electronic research, ...
,
New York New York most commonly refers to: * New York City, the most populous city in the United States, located in the state of New York * New York (state), a state in the northeastern United States New York may also refer to: Film and television * '' ...
. 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;"B-1B Background Information."
''Boeing''. Retrieved: 8 October 2009.
before the last B-1B was delivered, the USAF had determined that the aircraft was vulnerable to Soviet air defenses.Dao 2001, p.1


Design


Overview

The B-1 has a
blended wing body A blended wing body (BWB), also known as blended body or hybrid wing body (HWB), is a fixed-wing aircraft having no clear dividing line between the wings and the main body of the craft. The aircraft has distinct wing and body structures, which ar ...
configuration, with
variable-sweep wing A variable-sweep wing, colloquially known as a "swing wing", is an airplane wing, or set of wings, that may be swept back and then returned to its original straight position during flight. It allows the aircraft's shape to be modified in fli ...
, four
turbofan engines The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which achieves mechanical ...
, triangular ride-control fins and
cruciform tail __NOTOC__ The cruciform tail is an aircraft empennage configuration which, when viewed from the aircraft's front or rear, looks much like a cross. The usual arrangement is to have the horizontal stabilizer intersect the vertical tail somewhere ...
. The wings can sweep from 15 degrees to 67.5 degrees (full forward to full sweep). Forward-swept wing settings are used for
takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a ...
,
landing Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...
s and high-altitude economical
cruise A cruise is any travel on a cruise ship. Cruise or Cruises may also refer to: Tourism * Booze cruise * Music cruise * River cruise Aeronautics and aircraft * Cruise (aeronautics), a distinct stage of an aircraft's flight * Aviasouz Cruise, a R ...
. Aft-swept wing settings are used in high subsonic and supersonic flight. The B-1's variable-sweep wings and
thrust-to-weight ratio Thrust-to-weight ratio is a dimensionless ratio of thrust to weight of a rocket, jet engine, propeller engine, or a vehicle propelled by such an engine that is an indicator of the performance of the engine or vehicle. The instantaneous thrust-to- ...
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. Unlike the B-1A, the B-1B cannot reach Mach 2+ speeds; its maximum speed is Mach 1.25 (about 950 mph or 1,530 km/h at altitude), but its low-level speed increased to Mach 0.92 (700 mph, 1,130 km/h). The speed of the current version of the aircraft is limited by the need to avoid damage to its structure and air intakes. To help lower its RCS, the B-1B uses serpentine air intake ducts (see
S-duct An S-duct (or '' serpentine inlet'') is a type of jet engine intake duct used in several types of trijet aircraft. In this configuration, the intake is in the upper rear center of the aircraft, above or below the stabilizer, while the exhaust and ...
) and fixed intake ramps, which limit its speed compared to the B-1A. Vanes in the intake ducts serve to deflect and shield radar returns from the highly reflective engine compressor blades. The B-1A's engine was modified slightly to produce the GE F101-102 for the B-1B, with an emphasis on durability, and increased efficiency. The core from this engine was subsequently used in several other engines, including the GE F110 used in the
F-14 Tomcat The Grumman F-14 Tomcat is an American carrier-capable supersonic aircraft, supersonic, twinjet, twin-engine, two-seat, twin-tail, variable-sweep wing fighter aircraft. The Tomcat was developed for the United States Navy's Naval Fighter Experi ...
, F-15K/SG variants and later versions of the
General Dynamics F-16 Fighting Falcon The General Dynamics F-16 Fighting Falcon is a single-engine multirole fighter aircraft originally developed by General Dynamics for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a success ...
."F110 Family."
''GE Aviation.'' Retrieved: 25 January 2010
It is also the basis for the non- afterburning GE F118 used in the B-2 Spirit and the
U-2S The Lockheed U-2, nicknamed "''Dragon Lady''", is an American single-jet engine, high altitude reconnaissance aircraft operated by the United States Air Force (USAF) and previously flown by the Central Intelligence Agency (CIA). It provides day ...
. The F101 engine core is also used in the
CFM56 The CFM International CFM56 (U.S. military designation F108) series is a Franco-American family of high-bypass turbofan aircraft engines made by CFM International (CFMI), with a thrust range of . CFMI is a 50–50 joint-owned company of Safran ...
civil engine. The nose-gear door is the location for ground-crew control of the
auxiliary power unit An auxiliary power unit (APU) is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft and naval ships as well as some large land vehicles. Aircraft APUs generally produce 115& ...
(APU) which can be used during a scramble for quick-starting the APU.


Avionics

The B-1's main computer is the
IBM AP-101 The IBM System/4 Pi is a family of avionics computers used, in various versions, on the F-15 Eagle fighter, E-3 Sentry AWACS, Harpoon Missile, NASA's Skylab, MOL, and the Space Shuttle, as well as other aircraft. Development began in 1965, d ...
, which was also used on the
Space Shuttle orbiter The Space Shuttle orbiter is the spaceplane component of the Space Shuttle, a partially reusable orbital spacecraft system that was part of the discontinued Space Shuttle program. Operated from 1977 to 2011 by NASA, the U.S. space agency, thi ...
and the B-52 bomber. The computer is programmed with the
JOVIAL JOVIAL is a high-level programming language based on ALGOL 58, specialized for developing embedded systems (specialized computer systems designed to perform one or a few dedicated functions, usually embedded as part of a larger, more complete dev ...
programming language. The Lancer's offensive
avionics Avionics (a blend of ''aviation'' and ''electronics'') are the electronic systems used on aircraft. Avionic systems include communications, navigation, the display and management of multiple systems, and the hundreds of systems that are fit ...
include the Westinghouse (now
Northrop Grumman Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military tech ...
) AN/APQ-164 forward-looking offensive passive electronically scanned array radar set with electronic beam steering (and a fixed antenna pointed downward for reduced radar observability),
synthetic aperture radar Synthetic-aperture radar (SAR) is a form of radar that is used to create two-dimensional images or three-dimensional reconstructions of objects, such as landscapes. SAR uses the motion of the radar antenna over a target region to provide fine ...
, ground
moving target indication Moving target indication (MTI) is a mode of operation of a radar to discriminate a target against the clutter. It describes a variety of techniques used for finding moving objects, like an aircraft, and filter out unmoving ones, like hills or tree ...
(GMTI), and
terrain-following radar Terrain-following radar (TFR) is a military aerospace technology that allows a very-low-flying aircraft to automatically maintain a relatively constant altitude above ground level and therefore make detection by enemy radar more difficult. It is ...
modes,
Doppler navigation The Doppler effect or Doppler shift (or simply Doppler, when in context) is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who d ...
,
radar altimeter A radar altimeter (RA), also called a radio altimeter (RALT), electronic altimeter, reflection altimeter, or low-range radio altimeter (LRRA), measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it t ...
, and an inertial navigation suite. The B-1B Block D upgrade added a
Global Positioning System The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite ...
(GPS) receiver beginning in 1995. The B-1's defensive electronics include the
Eaton Eaton may refer to: Buildings Canada * Eaton Centre, the name of various shopping malls in Canada due to having been anchored by an Eaton's store * Eaton's / John Maryon Tower, a cancelled skyscraper in Toronto * Eaton Hall (King City), a conferen ...
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 A radome (a portmanteau of radar and dome) is a structural, weatherproof enclosure that protects a radar antenna. The radome is constructed of material transparent to radio waves. Radomes protect the antenna from weather and conceal antenna e ...
. Also in the tail radome is the AN/ALQ-153
missile approach warning system A missile approach warning system (MAW) is part of the avionics package on some military aircraft. A sensor detects attacking missiles. Its automatic warning cues the pilot to make a defensive maneuver and deploy the available countermeasures to ...
(
pulse-Doppler radar A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. It combines the features of pulse radars and ...
). The ALQ-161 is linked to a total of eight AN/ALE-49
flare A flare, also sometimes called a fusée, fusee, or bengala in some Latin-speaking countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illumination, ...
dispensers located on top behind the canopy, which are handled by the AN/ASQ-184 avionics management system. Each AN/ALE-49 dispenser has a capacity of 12 MJU-23A/B flares. The MJU-23A/B flare is one of the world's largest
infrared countermeasure An infrared countermeasure (IRCM) is a device designed to protect aircraft from infrared homing ("heat seeking") missiles by confusing the missiles' infrared guidance system so that they miss their target (electronic countermeasure). Heat-see ...
flares at a weight of over . The B-1 has also been equipped to carry the
ALE-50 towed decoy system The AN/ALE-50 towed decoy system is an electronic countermeasure tool designed by Raytheon to protect multiple US military aircraft from air-to-air and surface-to-air radar-guided missiles. The AN/ALE-50 towed decoy system is an anti-missile c ...
.. ''U.S. Air Force''. Retrieved: 25 June 2017. Also aiding the B-1's survivability is its relatively low RCS. Although not technically a stealth aircraft, thanks to the aircraft's structure, serpentine intake paths and use of
radar-absorbent material In materials science, radiation-absorbent material, usually known as RAM, is a material which has been specially designed and shaped to absorb incident RF radiation (also known as non-ionising radiation), as effectively as possible, from as ma ...
its RCS is about 1/50th that of the similar sized B-52. This is approximately 26 ft2 or 2.4 m2, comparable to that of a small
fighter aircraft Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...
. The B-1 holds 61 FAI world records for speed, payload, distance, and time-to-climb in different aircraft weight classes. 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 The National Aeronautic Association of the United States (NAA) is a non-profit 501(c)(3) organization and a founding member of the Fédération Aéronautique Internationale (FAI). Founded in 1905, it is the oldest national aviation club in the Uni ...
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. CMUP was delivered through a series of upgrades: *Block A was the standard B-1B with the capability to deliver non-precision gravity bombs. *Block B brought an improved Synthetic Aperture Radar, and upgrades to the Defensive Countermeasures System and was fielded in 1995. *Block C provided an "enhanced capability" for delivery of up to 30 cluster bomb units (CBUs) per
sortie A sortie (from the French word meaning ''exit'' or from Latin root ''surgere'' meaning to "rise up") is a deployment or dispatch of one military unit, be it an aircraft An aircraft is a vehicle that is able to flight, fly by gaining supp ...
with modifications made to 50 bomb racks. *Block D added a "Near Precision Capability" via improved weapons and targeting systems, and added advanced secure communications capabilities. The first part of the electronic countermeasures upgrade added
Joint Direct Attack Munition The Joint Direct Attack Munition (JDAM) is a guidance kit that converts unguided bombs, or "dumb bombs", into all-weather precision-guided munitions. JDAM-equipped bombs are guided by an integrated inertial guidance system coupled to a Global Po ...
(JDAM), ALE-50 towed decoy system, and anti-jam radios. *Block E upgraded the avionics computers and incorporated the Wind Corrected Munitions Dispenser (WCMD), the
AGM-154 Joint Standoff Weapon The AGM-154 Joint Standoff Weapon (JSOW) is a glide bomb that resulted from a joint venture between the United States Navy and Air Force to deploy a standardized medium range precision guided weapon, especially for engagement of defended targets ...
(JSOW) and the AGM-158 JASSM (Joint Air to Surface Standoff Munition), substantially improving the bomber's capability. 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. The pod is mounted on an external hardpoint at the aircraft's chin near the forward bomb bay. Following accelerated testing, the Sniper pod was fielded in summer 2008. Future precision munitions include the
Small Diameter Bomb The GBU-39/B Small Diameter Bomb (SDB) is a precision-guided glide bomb that is intended to provide aircraft with the ability to carry a higher number of more accurate bombs. Most US Air Force aircraft will be able to carry (using the BRU-61/A ...
. 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). FIDL enables electronic data sharing, eliminating the need to enter information between systems by hand. VSDU replaces existing flight instruments with multifunction color displays, a second display aids with threat evasion and targeting, and acts as a back-up display. CITS saw a new diagnostic system installed that allows crew to monitor over 9,000 parameters on the aircraft. Other additions are to replace the two spinning mass gyroscopic inertial navigation system with ring laser gyroscopic systems and a GPS antenna, replacement of the APQ-164 radar with the Scalable Agile Beam Radar – Global Strike (
SABR-GS The Northrop Grumman AN/APG-83 Scalable Agile Beam Radar (SABR) is a full-performance fire control radar for the General Dynamics F-16 Fighting Falcon and other aircraft. SABR is a multi-function active electronically scanned array (AESA) rada ...
)
active electronically scanned array An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled array antenna in which the beam of radio waves can be electronically steered to point in different directions without moving the an ...
, and a new attitude indicator.Air Force Begins Massive B-1B Overhaul
– Defensetech.org, 21 February 2014
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. Using the moveable forward bulkhead, space in the intermediate bay was increased from 180 to 269 in (457 to 683 cm). Expanding the internal bay to make use of the Common Strategic Rotary Launcher (CSRL), as well as utilizing six of the eight external hardpoints that had been previously out of use to keep in line with the New START Treaty, would increase the B-1B's weapon load from 24 to 40. The configuration also enables it to carry heavier weapons in the 5,000 lb (2,300 kg) range, such as
hypersonic In aerodynamics, a hypersonic speed is one that exceeds 5 times the speed of sound, often stated as starting at speeds of Mach 5 and above. The precise Mach number at which a craft can be said to be flying at hypersonic speed varies, since ind ...
missiles; the
AGM-183 ARRW The AGM-183 ARRW ("Air-Launched Rapid Response Weapon") is a hypersonic air-to-ground missile planned for use by the United States Air Force. Developed by Lockheed Martin, the boost-glide vehicle is propelled to a maximum speed of more than Mac ...
is planned for integration onto the bomber. In the future the HAWC could be used by the bomber which, combining both internal and external weapon carriage, could conceivably bring the total number of hypersonic weapons to 31.


Operational history


Strategic Air Command

The second B-1B, "The Star of Abilene", was the first B-1B delivered to SAC in June 1985. Initial operational capability was reached on 1 October 1986 and the B-1B was placed on nuclear alert status. The B-1 received the official name "Lancer" on 15 March 1990. However, the bomber has been commonly called the "Bone"; a nickname that appears to stem from an early newspaper article on the aircraft wherein its name was phonetically spelled out as "B-ONE" with the hyphen inadvertently omitted. In late 1990, engine fires in two Lancers led to a grounding of the fleet. The cause was traced back to problems in the first-stage fan, 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. By 1991, the B-1 had a fledgling conventional capability, forty of them able to drop the Mk-82 General Purpose (GP) bomb, although mostly from low altitude. Despite being cleared for this role, the problems with the engines prevented their use in
Operation Desert Storm Operation or Operations may refer to: Arts, entertainment and media * ''Operation'' (game), a battery-operated board game that challenges dexterity * Operation (music), a term used in musical set theory * ''Operations'' (magazine), Multi-Ma ...
during the
Gulf War The Gulf War was a 1990–1991 armed campaign waged by a 35-country military coalition in response to the Iraqi invasion of Kuwait. Spearheaded by the United States, the coalition's efforts against Iraq were carried out in two key phases: ...
. B-1s were primarily reserved for strategic nuclear strike missions at this time, providing the role of airborne nuclear deterrent against the Soviet Union. The B-52 was more suited to the role of conventional warfare and it was used by coalition forces instead. Originally designed strictly for nuclear war, the B-1's development as an effective conventional bomber was delayed. The collapse of the Soviet Union had brought the B-1's nuclear role into question, leading to President George H. W. Bush ordering a $3 billion conventional refit.Dao 2001, p. 4. After the inactivation of SAC and the establishment of the
Air Combat Command Air Combat Command (ACC) is one of nine Major Commands (MAJCOMs) in the United States Air Force, reporting to Headquarters, United States Air Force (HAF) at the Pentagon. It is the primary provider of air combat forces for the Air Force, and i ...
(ACC) in 1992, the B-1 developed a greater conventional weapons capability. Part of this development was the start-up of the U.S. Air Force Weapons School B-1 Division. In 1994, two additional B-1 bomb wings were also created in the
Air National Guard The Air National Guard (ANG), also known as the Air Guard, is a federal military reserve force of the United States Air Force, as well as the air militia of each U.S. state, the District of Columbia, the Commonwealth of Puerto Rico, and the ter ...
, with former fighter wings in the
Kansas Air National Guard The Kansas Air National Guard (KS ANG) is the aerial militia of the State of Kansas, United States of America. It is, along with the Kansas Army National Guard, an element of the Kansas National Guard. As state militia units, the units in the K ...
and the Georgia Air National Guard converting to the aircraft. By the mid-1990s, the B-1 could employ GP weapons as well as various CBUs. By the end of the 1990s, with the advent of the "Block D" upgrade, the B-1 boasted a full array of guided and unguided munitions. The B-1B no longer carries nuclear weapons; its nuclear capability was disabled by 1995 with the removal of nuclear arming and fuzing hardware. Under provisions of the
New START New START ( Russian abbrev.: СНВ-III, ''SNV-III'' from ''сокращение стратегических наступательных вооружений'' "reduction of strategic offensive arms") is a nuclear arms reduction treaty betwee ...
treaty with Russia, further conversions were performed. These included modification of aircraft hardpoints to prevent nuclear weapon pylons from being attached, removal of weapons bay wiring bundles for arming nuclear weapons, and destruction of nuclear weapon pylons. The conversion process was completed in 2011, and Russian officials inspect the aircraft every year to verify compliance.


Air Combat Command

The B-1 was first used in combat in support of operations in
Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...
during
Operation Desert Fox The 1998 bombing of Iraq (code-named Operation Desert Fox) was a major four-day bombing campaign on Iraqi targets from 16 to 19 December 1998, by the United States and the United Kingdom. On 16 December 1998, President of the United States Bill ...
in December 1998, employing unguided GP weapons. B-1s have been subsequently used in
Operation Allied Force The North Atlantic Treaty Organization (NATO) carried out an aerial bombing campaign against the Federal Republic of Yugoslavia during the Kosovo War. The air strikes lasted from 24 March 1999 to 10 June 1999. The bombings continued until an a ...
(Kosovo) and, most notably, in
Operation Enduring Freedom Operation Enduring Freedom (OEF) was the official name used synonymously by the U.S. government for both the War in Afghanistan (2001–2014) and the larger-scale Global War on Terrorism. On 7 October 2001, in response to the September 11 a ...
in Afghanistan and the
2003 invasion of Iraq The 2003 invasion of Iraq was a United States-led invasion of the Republic of Iraq and the first stage of the Iraq War. The invasion phase began on 19 March 2003 (air) and 20 March 2003 (ground) and lasted just over one month, including ...
. The B-1 has deployed an array of conventional weapons in war zones, most notably the GBU-31, JDAM. 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, notably on 7 April 2003 in an unsuccessful attempt to kill
Saddam Hussein Saddam Hussein ( ; ar, صدام حسين, Ṣaddām Ḥusayn; 28 April 1937 – 30 December 2006) was an Iraqi politician who served as the fifth president of Iraq from 16 July 1979 until 9 April 2003. A leading member of the revolutio ...
and his two sons. 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; this proposal resulted in several U.S. Air National Guard officers and members of Congress lobbying against the proposal, including the drafting of an amendment to prevent such cuts. The 2001 proposal was intended to allow money to be diverted to further upgrades to the remaining B-1Bs, such as computer modernization. In 2003, accompanied by the removal of B-1Bs from the two bomb wings in the Air National Guard, the USAF decided to retire 33 aircraft to concentrate its budget on maintaining availability of remaining B-1Bs. In 2004, a new
appropriation bill An appropriation, also known as supply bill or spending bill, is a proposed law that authorizes the expenditure of government funds. It is a bill that sets money aside for specific spending. In some democracies, approval of the legislature is ne ...
called for some retired aircraft to return to service, and the USAF returned seven mothballed bombers to service to increase the fleet to 67 aircraft.Mehuron, Tamar A
"USAF Almanac: Facts and Figures" (data as of 30 September 2004).
''Air Force Magazine,'' May 2005. Retrieved: 3 July 2011.
On 14 July 2007, the Associated Press reported on the growing USAF presence in Iraq, including reintroduction of B-1Bs as a close-at-hand platform to support Coalition ground forces.Hanley, Charles J
"Air Force Quietly Building Iraq Presence."
''commondreams.org'', 14 July 2007. Retrieved: 30 June 2011.
Beginning in 2008, B-1s were used in Iraq and Afghanistan in an "armed overwatch" role, loitering for surveillance purposes while ready to deliver guided bombs in support of ground troops as required.Door 2010, pp. 40–45. The B-1B underwent a series of flight tests using a 50/50 mix of synthetic and petroleum fuel; on 19 March 2008, a B-1B from
Dyess Air Force Base Dyess Air Force Base (AFB) is a United States Air Force (USAF) base located about southwest of downtown Abilene, Texas, and west of Fort Worth, Texas. The host unit at Dyess is the 7th Bomb Wing assigned to the Global Strike Command E ...
, Texas, became the first USAF aircraft to fly at supersonic speed using a synthetic fuel during a flight over Texas and New Mexico. This was conducted as part of an USAF testing and certification program to reduce reliance on traditional oil sources. On 4 August 2008, a B-1B flew the first Sniper Advanced Targeting Pod equipped combat sortie where the crew successfully targeted enemy ground forces and dropped a GBU-38 guided bomb in Afghanistan.Pate, Capt. Kristen. ''US Air Force'', 11 August 2008. Retrieved: 8 October 2009. In March 2011, B-1Bs from
Ellsworth Air Force Base Ellsworth Air Force Base (AFB) is a United States Air Force base located about northeast of Rapid City, South Dakota, just north of the town of Box Elder. The host unit at Ellsworth is the 28th Bomb Wing (28 BW). Assigned to the Global Str ...
attacked undisclosed targets in
Libya Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to the east, Suda ...
as part of
Operation Odyssey Dawn Operation Odyssey Dawn was the U.S. code name for the American role in the international military operation in Libya to enforce United Nations Security Council Resolution 1973 during the initial period of 19–31 March 2011, which continued af ...
. With upgrades to keep the B-1 viable, the USAF may keep it in service until approximately 2038. Despite upgrades, a single flight hour needs 48.4 hours of repair. The fuel, repairs, and other needs for a 12-hour mission cost $720,000 as of 2010. The $63,000 cost per flight hour is, however, less than the $72,000 for the B-52 and the $135,000 of the B-2.Axe, David
"Why Can't the Air Force Build an Affordable Plane?"
''The Atlantic,'' 26 March 2012. Retrieved: 30 June 2012.
In June 2010, senior USAF officials met to consider retiring the entire fleet to meet budget cuts. The Pentagon plans to begin replacing the aircraft with the
B-21 Raider The Northrop Grumman B-21 Raider is an American strategic bomber under development for the United States Air Force (USAF) by Northrop Grumman. As part of the Long Range Strike Bomber (LRS-B) program, it is to be a long-range, stealth interc ...
after 2025. In the meantime, its "capabilities are particularly well-suited to the vast distances and unique challenges of the Pacific region, and we'll continue to invest in, and rely on, the B-1 in support of the focus on the Pacific" as part of President Obama's "Pivot to East Asia". In August 2012, the 9th Expeditionary Bomb Squadron returned from a six-month tour in Afghanistan. Its 9 B-1Bs flew 770 sorties, the most of any B-1B squadron on a single deployment. The squadron spent 9,500 hours airborne, keeping one of its bombers in the air at all times. They accounted for a quarter of all combat aircraft sorties over the country during that time and fulfilled an average of two to three air support requests per day. On 4 September 2013, a B-1B participated in a maritime evaluation exercise, deploying munitions such as laser-guided 500 lb GBU-54 bombs, 500 lb and 2,000 lb JDAM, and Long Range Anti-Ship Missiles (LRASM). The aim was to detect and engage several small craft using existing weapons and tactics developed from conventional warfare against ground targets; the B-1 is seen as a useful asset for maritime duties such as patrolling shipping lanes. Beginning in 2014, the B-1 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 Operation Inherent Resolve (OIR) is the U.S. military's operational name for the International military intervention against IS, including both a campaign in Iraq and a campaign in Syria, with a closely-related campaign in Libya. Throu ...
. The 9th Bomb Squadron was deployed to Qatar in July 2014 to support missions in Afghanistan, but when the air campaign against IS began on 8 August, the aircraft were employed in Iraq. During the
Battle of Kobane A battle is an occurrence of combat in warfare between opposing military units of any number or size. A war usually consists of multiple battles. In general, a battle is a military engagement that is well defined in duration, area, and force ...
in Syria, the squadron's B-1s dropped 660 bombs over 5 months in support of Kurdish forces defending the city. This amounted to one-third of all bombs used during OIR during the period, and they killed some 1,000 ISIL fighters. The 9th Bomb Squadron's B-1s went "Winchester"–dropping all weapons on board–31 times during their deployment. They dropped over 2,000 JDAMs during the 6-month rotation. B-1s from the 28th Bomb Wing flew 490 sorties where they dropped 3,800 munitions on 3,700 targets during a six-month deployment. In February 2016, the B-1s were sent back to the U.S. for cockpit upgrades.


Air Force Global Strike Command

As part of a USAF reorganization announced in April 2015, all B-1s were reassigned from Air Combat Command to
Global Strike Command Air Force Global Strike Command (AFGSC) is a Major Command (MAJCOM) of the United States Air Force, headquartered at Barksdale Air Force Base, Louisiana. AFGSC provides combat-ready forces to conduct strategic nuclear deterrence and global s ...
(GSC) in October 2015. On 8 July 2017, the USAF flew two B-1s near the North Korean border in a show of force amid increasing tensions, particularly in response to North Korea's 4 July test of an ICBM capable of reaching Alaska. On 14 April 2018, B-1s launched 19 JASSM missiles as part of the
2018 bombing of Damascus and Homs On 14 April 2018, beginning at 04:00 Syrian time (UTC+3), the United States, France, and the United Kingdom carried out a series of military strikes involving aircraft and ship-based missiles against multiple government sites in Syria during ...
in Syria. In August 2019, six B-1Bs met full mission capablity; 15 were undergoing depot maintenance and 39 under repair and inspection. In February 2021, the USAF announced it will retire 17 B-1s, leaving 45 aircraft in service. Four of these will be stored in a condition that will allow their return to service if required. In March 2021, B-1s deployed to Norway's
Ørland Main Air Station Ørland Main Air Station (Norwegian: Ørland hovedflystasjon) is situated at the mouth of the Trondheimsfjorden in the municipality of Ørland in Trøndelag county in the center of Norway. Ørland is operated by the Royal Norwegian Air Force and i ...
for the first time. During the deployment, they conducted bombing training with Norwegian and Swedish ground force Joint terminal attack controllers. One B-1 also conducted a ''warm-pit refuel'' at
Bodø Main Air Station Bodø Air Station (; no, Bodø hovedflystasjon) is a military air base of the Royal Norwegian Air Force (RNoAF) located in the town of Bodø in Bodø Municipality, Nordland county, Norway. It is home to the General Dynamics F-16 Fighting Falcons ...
, marking the first landing inside Norway's
Arctic Circle The Arctic Circle is one of the two polar circles, and the most northerly of the five major circles of latitude as shown on maps of Earth. Its southern equivalent is the Antarctic Circle. The Arctic Circle marks the southernmost latitude at ...
, and integrated with four
Swedish Air Force The Swedish Air Force ( sv, Svenska flygvapnet or just ) is the air force branch of the Swedish Armed Forces. History The Swedish Air Force was created on 1 July, 1926 when the aircraft units of the Army and Navy were merged. Because of the e ...
JAS 39 Gripen The Saab JAS 39 Gripen (; English: ''griffin'') is a light single-engine multirole fighter aircraft manufactured by the Swedish aerospace and defense company Saab AB. The Gripen has a delta wing and canard configuration with relaxed stabilit ...
fighters.


Variants

;B-1A: The B-1A was the original B-1 design with variable engine intakes and Mach 2.2 top speed. Four prototypes were built; no production units were manufactured.Donald 1997, p. 723. ;B-1B: The B-1B is a revised B-1 design with reduced radar signature and a top speed of Mach 1.25. It is optimized for low-level penetration. A total of 100 B-1Bs were produced. ;B-1R: The B-1R was a 2004 proposed upgrade of existing B-1B aircraft. The B-1R (R for "regional") would be fitted with advanced radars,
air-to-air missile The newest and the oldest member of Rafael's Python family of AAM for comparisons, Python-5 (displayed lower-front) and Shafrir-1 (upper-back) An air-to-air missile (AAM) is a missile fired from an aircraft for the purpose of destroying a ...
s, and new Pratt & Whitney F119 engines (from the
Lockheed Martin F-22 Raptor The Lockheed Martin F-22 Raptor is an American single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). As the result of the USAF's Advanced Tactical Fighter (ATF) program, th ...
). This variant would have a top speed of Mach 2.2, but with 20% shorter range.Hebert, Adam J
"Long-Range Strike in a Hurry."
''Air Force Magazine'', November 2004. Retrieved: 8 October 2009.
Existing external hardpoints would be modified to allow multiple conventional weapons to be carried, increasing overall loadout. For air-to-air defense, an active electronically scanned array (AESA) radar would be added and some existing hardpoints modified to carry air-to-air missiles.


Operators

The USAF had 62 B-1Bs in service as of August 2017.


Aircraft on display

;B-1A: ;B-1B:


Accidents and incidents

From 1984 to 2001, ten B-1s were lost due to accidents with 17 crew members or people on board killed.
''
USA Today ''USA Today'' (stylized in all uppercase) is an American daily middle-market newspaper and news broadcasting company. Founded by Al Neuharth on September 15, 1982, the newspaper operates from Gannett's corporate headquarters in Tysons, Virgini ...
'', 12 December 2001. Retrieved: 18 July 2006.
* In September 1987, B-1B (
serial number A serial number is a unique identifier assigned incrementally or sequentially to an item, to ''uniquely'' identify it. Serial numbers need not be strictly numerical. They may contain letters and other typographical symbols, or may consist enti ...
84–0052) from the
96th Bomb Wing The 96th Test Wing is a United States Air Force unit assigned to the Air Force Test Center of Air Force Materiel Command at Eglin Air Force Base, Florida. The wing was activated at Eglin in 1994 as the 96th Air Base Wing, the headquarters for ...
, 338th Combat Crew Training Squadron, Dyess AFB, crashed near
La Junta, Colorado La Junta is a home rule municipality in , the county seat of, and the most populous municipality of Otero County, Colorado, United States. The city population was 7,322 at the 2020 United States Census. La Junta is located on the Arkansas ...
, while flying on a low-level training route. This was the only B-1B crash to occur with six crew members aboard. The two crew members in
jump seat In aviation, a jump seat or jumpseat is an auxiliary seat for individuals—other than normal passengers—who are not operating the aircraft. In general, the term 'jump seat' can also refer to a seat in any type of vehicle which can fold up out ...
s, and one of the four crew members in
ejection seat In aircraft, an ejection seat or ejector seat is a system designed to rescue the pilot or other crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rock ...
s perished. The root cause of the accident was thought to be a
bird strike A bird strike—sometimes called birdstrike, bird ingestion (for an engine), bird hit, or bird aircraft strike hazard (BASH)—is a collision between an airborne animal (usually a bird or bat) and a moving vehicle, usually an aircraft. The term ...
on a wing's leading edge during the low-level flight. The impact was severe enough to sever fuel and hydraulic lines on one side of the aircraft, the other side's engines functioned long enough to allow for ejection. The B-1B fleet was later modified to protect these supply lines. * In October 1990, while flying a training route in eastern Colorado, B-1B (86-0128) from the 384th Bomb Wing, 28th Bomb Squadron,
McConnell AFB McConnell Air Force Base is a United States Air Force base located four miles (6 km) southeast of the central business district of Wichita, a city in Sedgwick County, Kansas, United States., effective 2007-12-20 The airbase was named in ...
, experienced an explosion as the engines reached full power without afterburners. Fire on the aircraft's left was spotted. The No. 1 engine was shut down and its
fire extinguisher A fire extinguisher is a handheld active fire protection device usually filled with a dry or wet chemical used to extinguish or control small fires, often in emergencies. It is not intended for use on an out-of-control fire, such as one which ha ...
was activated. The accident investigation determined that the engine had suffered catastrophic failure, engine blades had cut through the engine mounts and the engine became detached from the aircraft. * In December 1990, B-1B (83-0071) from the 96th Bomb Wing, 337th Bomb Squadron, Dyess AFB, Texas, experienced a jolt that caused the No. 3 engine to shut down with its fire extinguisher activating. This event, coupled with the October 1990 engine incident, led to a 50+ day grounding of the B-1Bs not on nuclear alert status. The problem was eventually traced back to problems in the first-stage fan, and all B-1Bs were equipped with modified engines.


Specifications (B-1B)


Weapons loads


Notable appearances in media


See also


Notes


References


Bibliography

* * Dao, James
"Much-Maligned B-1 Bomber Proves Hard to Kill."
''The New York Times'', 1 August 2001. * Donald, David, ed. "Rockwell B-1B". ''The Complete Encyclopedia of World Aircraft''. New York: Barnes & Noble, 1997. . * . * * . * . * * * * * * * * * . * * * *


External links


B-1B Fact Sheet on af.mil

B-1B product page
an
B-1B history page on Boeing.com



B-1B Lancer in Airman Magazine's Airframe Profiles
* {{Authority control Aircraft first flown in 1974 Cruciform tail aircraft Quadjets B-001 1970s United States bomber aircraft Variable-sweep-wing aircraft Supersonic aircraft Strategic bombers