95-532: The Duck Club was a right-wing organization within the United States, founded in 1980 by a Florida businessman Robert White when he was diagnosed with cancer. In summer 1980 White published a magazine, and a cartoon featuring a duck in a B1 bomber defending the Panama Canal became the namesake of the clubs White founded. In 1983, White's cancer was responding to treatment and he began to restructure
190-540: A Global Positioning System (GPS) receiver beginning in 1995. The B-1's defensive electronics include the Eaton AN/ALQ-161A radar warning and defensive jamming equipment, which has three sets of antennas; one at the front base of each wing and the third rear-facing in the tail radome . Also in the tail radome is the AN/ALQ-153 missile approach warning system ( pulse-Doppler radar ). The ALQ-161
285-644: A 10,000-pound (4,500 kg) payload and a range of 10,070 miles (16,210 km) including 2,900 miles (4,700 km) flown at low altitudes. In August 1963, the similar Low-Altitude Manned Penetrator design was completed, which called for an aircraft with a 20,000-pound (9,100 kg) bomb load and somewhat shorter range of 8,230 miles (13,240 km). 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,
380-425: A channel becomes supersonic, one significant change takes place. The conservation of mass flow rate leads one to expect that contracting the flow channel would increase the flow speed (i.e. making the channel narrower results in faster air flow) and at subsonic speeds this holds true. However, once the flow becomes supersonic, the relationship of flow area and speed is reversed: expanding the channel actually increases
475-512: 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
570-439: A corresponding speed of sound (Mach 1) of 295.0 meters per second (967.8 ft/s; 659.9 mph; 1,062 km/h; 573.4 kn), 86.7% of the sea level value. The terms subsonic and supersonic are used to refer to speeds below and above the local speed of sound, and to particular ranges of Mach values. This occurs because of the presence of a transonic regime around flight (free stream) M = 1 where approximations of
665-407: A gas or a liquid. The boundary can be travelling in the medium, or it can be stationary while the medium flows along it, or they can both be moving, with different velocities : what matters is their relative velocity with respect to each other. The boundary can be the boundary of an object immersed in the medium, or of a channel such as a nozzle , diffuser or wind tunnel channelling the medium. As
760-430: A long-distance record for the aircraft, which demonstrated its ability to conduct extended mission lengths to strike anywhere in the world and return to base without any stops. The National Aeronautic Association recognized the B-1B for completing one of the 10 most memorable record flights for 1994. The B-1 has been upgraded since production, beginning with the "Conventional Mission Upgrade Program" (CMUP), which added
855-591: 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: 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
950-572: 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
1045-584: A new attitude indicator. 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
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#17327974556291140-494: 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 500-pound (230 kg) 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 during
1235-663: 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. Secretary of Defense Robert McNamara preferred ICBMs over bombers for
1330-619: 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 ) active electronically scanned array , and
1425-466: A sharp object, there is no air between the nose and the shock wave: the shock wave starts from the nose.) As the Mach number increases, so does the strength of the shock wave and the Mach cone becomes increasingly narrow. As the fluid flow crosses the shock wave, its speed is reduced and temperature, pressure, and density increase. The stronger the shock, the greater the changes. At high enough Mach numbers
1520-575: A six-engine bomber that could cruise at Mach 3 at high altitude (70,000 ft or 21,000 m). Soviet Union interceptor aircraft , the only effective anti-bomber weapon in the 1950s, were already unable to intercept the high-flying Lockheed U-2 ; the Valkyrie would fly at similar altitudes, but much higher speeds, and was expected to fly right by the fighters. By the late 1950s, however, anti-aircraft surface-to-air missiles (SAMs) could threaten high-altitude aircraft, as demonstrated by
1615-599: A supersonic compressible flow can be found from the Rayleigh supersonic pitot equation (above) using parameters for air: M ≈ 0.88128485 ( q c p + 1 ) ( 1 − 1 7 M 2 ) 2.5 {\displaystyle \mathrm {M} \approx 0.88128485{\sqrt {\left({\frac {q_{c}}{p}}+1\right)\left(1-{\frac {1}{7\,\mathrm {M} ^{2}}}\right)^{2.5}}}} where: As can be seen, M appears on both sides of
1710-769: A supersonic compressible flow is derived from the Rayleigh supersonic pitot equation: p t p = [ γ + 1 2 M 2 ] γ γ − 1 ⋅ [ γ + 1 1 − γ + 2 γ M 2 ] 1 γ − 1 {\displaystyle {\frac {p_{t}}{p}}=\left[{\frac {\gamma +1}{2}}\mathrm {M} ^{2}\right]^{\frac {\gamma }{\gamma -1}}\cdot \left[{\frac {\gamma +1}{1-\gamma +2\gamma \,\mathrm {M} ^{2}}}\right]^{\frac {1}{\gamma -1}}} Mach number
1805-439: 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 radar cross-section, the B-1B uses serpentine air intake ducts (see S-duct ) and fixed intake ramps , which limit its speed compared to
1900-461: Is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound . It is named after the Austrian physicist and philosopher Ernst Mach . M = u c , {\displaystyle \mathrm {M} ={\frac {u}{c}},} where: By definition, at Mach 1, the local flow velocity u is equal to
1995-642: Is a function of temperature and true airspeed. Aircraft flight instruments , however, operate using pressure differential to compute Mach number, not temperature. Assuming air to be an ideal gas , the formula to compute Mach number in a subsonic compressible flow is found from Bernoulli's equation for M < 1 (above): M = 5 [ ( q c p + 1 ) 2 7 − 1 ] {\displaystyle \mathrm {M} ={\sqrt {5\left[\left({\frac {q_{c}}{p}}+1\right)^{\frac {2}{7}}-1\right]}}\,} The formula to compute Mach number in
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#17327974556292090-550: Is linked to a total of eight AN/ALE-49 flare 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 flares at a weight of over 3.3 pounds (1.5 kg). The B-1 has also been equipped to carry the ALE-50 towed decoy system . Also aiding
2185-418: Is not a constant; in a gas, it increases proportionally to the square root of the absolute temperature , and since atmospheric temperature generally decreases with increasing altitude between sea level and 11,000 meters (36,089 ft), the speed of sound also decreases. For example, the standard atmosphere model lapses temperature to −56.5 °C (−69.7 °F) at 11,000 meters (36,089 ft) altitude, with
2280-800: Is one of the United States Air Force's three strategic bombers , along with the B-2 Spirit and the B-52 Stratofortress . Its 75,000-pound (34,000 kg) payload is the heaviest of any U.S. bomber. The B-1 was first envisioned in the 1960s as a bomber that would combine the Mach 2 speed of the B-58 Hustler with the range and payload of the B-52, ultimately replacing both. After a long series of studies, North American Rockwell (subsequently renamed Rockwell International , B-1 division later acquired by Boeing ) won
2375-621: Is that range of speeds within which the airflow over different parts of an aircraft is between subsonic and supersonic. So the regime of flight from Mcrit up to Mach 1.3 is called the transonic range. Aircraft designed to fly at supersonic speeds show large differences in their aerodynamic design because of the radical differences in the behavior of flows above Mach 1. Sharp edges, thin aerofoil sections, and all-moving tailplane / canards are common. Modern combat aircraft must compromise in order to maintain low-speed handling. Flight can be roughly classified in six categories: At transonic speeds,
2470-468: 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
2565-462: The B-2 stealth bomber program. The B-1A design was altered, reducing top speed to Mach 1.25 at high altitude , 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 1985; the plane formally entered service with Strategic Air Command (SAC) as a nuclear bomber
2660-702: The General Dynamics F-16 Fighting Falcon . It is also the basis for the non- afterburning GE F118 used in the B-2 Spirit and the U-2S . The F101 engine core is also used in the CFM56 civil engine. The nose-gear door is the location for ground-crew control of the auxiliary power unit (APU) which can be used during a scramble for quick-starting the APU. The B-1's main computer is
2755-532: The Gulf War . 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
2850-885: The IBM AP-101 , which was also used on the Space Shuttle orbiter and the B-52 bomber. The computer is programmed with the JOVIAL programming language . The Lancer's offensive avionics include the Westinghouse (now Northrop Grumman ) 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 , ground moving target indication (GMTI), and terrain-following radar modes, Doppler navigation , radar altimeter , and an inertial navigation suite. The B-1B Block D upgrade added
2945-750: The Navier-Stokes equations used for subsonic design no longer apply; the simplest explanation is that the flow around an airframe locally begins to exceed M = 1 even though the free stream Mach number is below this value. Meanwhile, the supersonic regime is usually used to talk about the set of Mach numbers for which linearised theory may be used, where for example the ( air ) flow is not chemically reacting, and where heat-transfer between air and vehicle may be reasonably neglected in calculations. Generally, NASA defines high hypersonic as any Mach number from 10 to 25, and re-entry speeds as anything greater than Mach 25. Aircraft operating in this regime include
Duck Club - Misplaced Pages Continue
3040-670: The Northwest Territorial Imperative , an irredentist movement to establish a White homeland in the Pacific Northwest. On July 19, 1988, Robert White was shot and killed in rural Belize , in what was believed to be a robbery. B1 bomber The Rockwell B-1 Lancer is a supersonic variable-sweep wing , heavy bomber used by the United States Air Force . It has been nicknamed the "Bone" (from "B-One"). As of 2024 , it
3135-748: The Small Diameter Bomb . The USAF commenced the Integrated Battle Station (IBS) modification in 2012 as a combination of three separate upgrades when it realised the benefits of completing them concurrently; the Fully Integrated Data Link (FIDL), Vertical Situational Display Unit (VSDU) 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,
3230-421: The Space Shuttle and various space planes in development. The subsonic speed range is that range of speeds within which, all of the airflow over an aircraft is less than Mach 1. The critical Mach number (Mcrit) is lowest free stream Mach number at which airflow over any part of the aircraft first reaches Mach 1. So the subsonic speed range includes all speeds that are less than Mcrit. The transonic speed range
3325-557: 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 60,000 pounds (27,000 kg), 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. Although effective,
3420-551: The compressibility characteristics of fluid flow : the fluid (air) behaves under the influence of compressibility in a similar manner at a given Mach number, regardless of other variables. As modeled in the International Standard Atmosphere , dry air at mean sea level , standard temperature of 15 °C (59 °F), the speed of sound is 340.3 meters per second (1,116.5 ft/s; 761.23 mph; 1,225.1 km/h; 661.49 kn). The speed of sound
3515-400: The sound barrier ), a large pressure difference is created just in front of the aircraft . This abrupt pressure difference, called a shock wave , spreads backward and outward from the aircraft in a cone shape (a so-called Mach cone ). It is this shock wave that causes the sonic boom heard as a fast moving aircraft travels overhead. A person inside the aircraft will not hear this. The higher
3610-696: The Air Force has 45 B-1Bs. The Northrop Grumman B-21 Raider is to begin replacing the B-1B after 2025; all B-1s are planned to be retired by 2036. 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,
3705-516: The Air Force portion of the deterrent force and felt a new expensive bomber was not needed. McNamara limited the AMSA program to studies and component development beginning in 1964. Program studies continued; IBM and Autonetics were awarded AMSA advanced avionics study contracts in 1968. McNamara 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
3800-468: 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
3895-513: 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 its RCS is about 1/50th that of the similar sized B-52. This is approximately 26 ft or 2.4 m , comparable to that of a small fighter aircraft . 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
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3990-665: 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 , F-15K/SG variants and later versions of
4085-415: 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
4180-432: 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 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
4275-425: 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 , 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
4370-524: The B-58. He again vetoed funding for AMSA aircraft development in 1968. 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
4465-622: The Duck Club organization to stem financial losses. Among White's subscribers, David Lewis Rice was a member of the Duck Club, and in 1985 murdered four members of the Goldmark family in Seattle, mistakenly believing them to be Communists. A 1988 report by the Center for World Indigenous Studies lists the Duck Club as one of several anti-Native American organizations operating in support of
4560-488: 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. With the wings set to their widest position the aircraft had a much better airfield performance than
4655-399: The Mach number is defined as the ratio of two speeds, it is a dimensionless quantity. If M < 0.2–0.3 and the flow is quasi-steady and isothermal , compressibility effects will be small and simplified incompressible flow equations can be used. The Mach number is named after the physicist and philosopher Ernst Mach , in honour of his achievements, according to a proposal by
4750-619: 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 1981, it
4845-481: 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. On 26 April 1991, ten B-1Bs narrowly avoided being hit by the 1991 Andover tornado while located at McConnell AFB , which took a direct hit. Two of the bombers were equipped with nuclear warheads. Mach number The Mach number ( M or Ma ), often only Mach , ( / m ɑː k / ; German: [max] )
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#17327974556294940-445: The U.S. Air Force. During the 1980 presidential campaign, Ronald Reagan campaigned heavily on the platform that Carter was weak on defense, citing the cancellation of the B-1 program as an example, a theme he continued using into the 1980s. 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. On taking office, Reagan
5035-452: The USAF equal capability of penetrating Soviet airspace. With a range of 1,500 miles (2,400 km), 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
5130-451: 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 actually stood for "America's Most Studied Aircraft". The arguments that led to
5225-456: The aeronautical engineer Jakob Ackeret in 1929. The word Mach is always capitalized since it derives from a proper name, and since the Mach number is a dimensionless quantity rather than a unit of measure , the number comes after the word Mach. It was also known as Mach's number by Lockheed when reporting the effects of compressibility on the P-38 aircraft in 1942. Mach number is a measure of
5320-582: 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
5415-411: 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
5510-454: 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
5605-470: The bomber which, combining both internal and external weapon carriage, could conceivably bring the total number of hypersonic weapons to 31. 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,
5700-428: 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 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
5795-441: The decision. NATO commander Alexander Haig 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
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#17327974556295890-405: 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
5985-545: The design contest for what emerged as the B-1A. Prototypes of this version could fly Mach 2.2 at high altitude and long distances at Mach 0.85 at very low altitudes. The program was canceled in 1977 due to its high cost, the introduction of the AGM-86 cruise missile that flew the same basic speed and distance, and early work on the B-2 stealth bomber. The program was restarted in 1981, largely as an interim measure due to delays in
6080-539: 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. In 1976, Soviet pilot Viktor Belenko defected to Japan with his MiG-25 "Foxbat" . During debriefing he described
6175-454: The design of which was tuned for high-altitude performance. Higher aerodynamic drag 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 (ICBM) force, the B-70 bomber program was cancelled in 1961 by President John F. Kennedy , and
6270-586: 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
6365-577: 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 missiles; the AGM-183 ARRW is planned for integration onto the bomber. In the future the HAWC could be used by
6460-473: The equation, and for practical purposes a root-finding algorithm must be used for a numerical solution (the equation is a septic equation in M and, though some of these may be solved explicitly, the Abel–Ruffini theorem guarantees that there exists no general form for the roots of these polynomials). It is first determined whether M is indeed greater than 1.0 by calculating M from the subsonic equation. If M
6555-402: 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 capability). The switch from high-altitude to low-altitude flight profiles severely affected the B-70,
6650-408: The flow field around the object includes both sub- and supersonic parts. The transonic period begins when first zones of M > 1 flow appear around the object. In case of an airfoil (such as an aircraft's wing), this typically happens above the wing. Supersonic flow can decelerate back to subsonic only in a normal shock; this typically happens before the trailing edge. (Fig.1a) As the speed increases,
6745-705: The following year. By 1988, all 100 aircraft had been delivered. With the disestablishment of SAC and its reassignment to the Air Combat Command in 1992, the B-1B's nuclear capabilities were disabled and it was outfitted for conventional bombing. It first served in combat during Operation Desert Fox in 1998 and again during the NATO action in Kosovo the following year. The B-1B has supported U.S. and NATO military forces in Afghanistan and Iraq . As of 2021
6840-521: 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 United States Navy 's carrier-based attack aircraft, leaving this role to
6935-414: 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 for each crew member. The B-1A mockup review occurred in late October 1971; this resulted in 297 requests for alteration to
7030-502: 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
7125-418: The radar (and human observers) incapable of seeing it. Additionally, radars of the era were subject to " clutter " 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
7220-473: The required Mach 2 performance at high altitudes, the exhaust nozzles and air intake ramps 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
7315-463: The speed of sound is known, the Mach number at which an aircraft is flying can be calculated by M = u c {\displaystyle \mathrm {M} ={\frac {u}{c}}} where: and the speed of sound varies with the thermodynamic temperature as: c = γ ⋅ R ∗ ⋅ T , {\displaystyle c={\sqrt {\gamma \cdot R_{*}\cdot T}},} where: If
7410-779: The speed of sound is not known, Mach number may be determined by measuring the various air pressures (static and dynamic) and using the following formula that is derived from Bernoulli's equation for Mach numbers less than 1.0. Assuming air to be an ideal gas , the formula to compute Mach number in a subsonic compressible flow is: M = 2 γ − 1 [ ( q c p + 1 ) γ − 1 γ − 1 ] {\displaystyle \mathrm {M} ={\sqrt {{\frac {2}{\gamma -1}}\left[\left({\frac {q_{c}}{p}}+1\right)^{\frac {\gamma -1}{\gamma }}-1\right]}}\,} where: The formula to compute Mach number in
7505-418: The speed of sound. At Mach 0.65, u is 65% of the speed of sound (subsonic), and, at Mach 1.35, u is 35% faster than the speed of sound (supersonic). The local speed of sound, and hence the Mach number, depends on the temperature of the surrounding gas. The Mach number is primarily used to determine the approximation with which a flow can be treated as an incompressible flow . The medium can be
7600-405: The speed, the more narrow the cone; at just over M = 1 it is hardly a cone at all, but closer to a slightly concave plane. At fully supersonic speed, the shock wave starts to take its cone shape and flow is either completely supersonic, or (in case of a blunt object), only a very small subsonic flow area remains between the object's nose and the shock wave it creates ahead of itself. (In the case of
7695-425: The speed. The obvious result is that in order to accelerate a flow to supersonic, one needs a convergent-divergent nozzle, where the converging section accelerates the flow to sonic speeds, and the diverging section continues the acceleration. Such nozzles are called de Laval nozzles and in extreme cases they are able to reach hypersonic speeds (Mach 13 (15,900 km/h; 9,900 mph) at 20 °C). When
7790-399: The temperature increases so much over the shock that ionization and dissociation of gas molecules behind the shock wave begin. Such flows are called hypersonic. It is clear that any object travelling at hypersonic speeds will likewise be exposed to the same extreme temperatures as the gas behind the nose shock wave, and hence choice of heat-resistant materials becomes important. As a flow in
7885-444: 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 suites to deal with radars. During
7980-508: 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." Western military leaders were generally happy with
8075-437: The zone of M > 1 flow increases towards both leading and trailing edges. As M = 1 is reached and passed, the normal shock reaches the trailing edge and becomes a weak oblique shock: the flow decelerates over the shock, but remains supersonic. A normal shock is created ahead of the object, and the only subsonic zone in the flow field is a small area around the object's leading edge. (Fig.1b) When an aircraft exceeds Mach 1 (i.e.
8170-562: 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
8265-504: Was believed the B-1 could be in operation before the ATB, covering the transitional period between the B-52's increasing vulnerability and the ATB's introduction. Reagan decided the best solution was to procure both the B-1 and ATB, and on 2 October 1981 he announced that 100 B-1s were to be ordered to fill the LRCA role. In January 1982, the U.S. Air Force awarded two contracts to Rockwell worth
8360-961: 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 B‑;1 as of 2024. The B-1 has a blended wing body configuration, with variable-sweep wing , four turbofan engines , triangular ride-control fins and cruciform tail . The wings can sweep from 15 degrees to 67.5 degrees (full forward to full sweep). Forward-swept wing settings are used for takeoff , landings and high-altitude economical cruise . Aft-swept wing settings are used in high subsonic and supersonic flight. The B-1's variable-sweep wings and thrust-to-weight ratio provide it with improved takeoff performance, allowing it to use shorter runways than previous bombers. The length of
8455-463: 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,
8550-504: 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
8645-560: Was made public with the program being top secret , but it is now known that in early 1978 he authorized the Advanced Technology Bomber (ATB) project, which eventually led to the B-2 Spirit . Domestically, the reaction to the cancellation was split along partisan lines. 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
8740-745: Was reached by the second B-1A. Engine testing also continued during this time with the YF101 engines totaling almost 7,600 hours. 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
8835-434: 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 477,000 pounds (216,000 kg) from the B-1A's 395,000 pounds (179,000 kg). The weight increase
8930-478: 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
9025-423: 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 was minimal. 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
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