Introduction Although the B-52A was the first production variant, these aircraft were used only in testing. The first operational version was the B-52B, which had been developed in parallel with the prototypes since 1951. First flying in December 1954, B-52B, AF Serial Number 52-8711, entered operational service with
93rd Heavy Bombardment Wing (93rd BW) at
Castle Air Force Base, California, on 29 June 1955. The wing became operational on 12 March 1956. The training for B-52 crews consisted of five weeks of ground school and four weeks of flying, accumulating 35 to 50 hours in the air. The new B-52Bs replaced operational B-36s on a one-to-one basis. Early operations were problematic; in addition to supply problems, there were also technical issues. Ramps and taxiways deteriorated under the aircraft's weight, the fuel system was prone to leaks and icing, and bombing and fire control computers were unreliable. The split-level cockpit presented a temperature control problem– the pilots' cockpit was heated by sunlight while the observer and the navigator on the bottom deck sat on the ice-cold floor. Thus, a comfortable temperature setting for the pilots caused the other crew members to freeze, while a comfortable temperature for the bottom crew caused the pilots to overheat. The J57 engines proved unreliable.
Alternator failure caused the first fatal B-52 crash in February 1956; as a result, the fleet was briefly grounded. In July, fuel and hydraulic issues grounded the B-52s again. In response to maintenance issues, the USAF set up "Sky Speed" teams of 50 contractors at each B-52 base to perform maintenance and routine checkups, taking an average of one week per aircraft. for Castle Air Force Base, California, after their record-setting round-the-world flight in 1957. On 21 May 1956, a B-52B (52–13) dropped a
Mk-15 nuclear bomb over the
Bikini Atoll in a test code-named
Cherokee. It was the first air-dropped
thermonuclear weapon. This aircraft now is on display at the
National Museum of Nuclear Science and History in
Albuquerque,
New Mexico. From 24 to 25 November 1956, four B-52Bs of the 93rd BW and four B-52Cs of the 42nd BW flew nonstop around the perimeter of North America in
Operation Quick Kick, which covered in 31 hours, 30 minutes. SAC noted the flight time could have been reduced by 5 to 6 hours had the four inflight refuelings been done by fast jet-powered tanker aircraft rather than propeller-driven
Boeing KC-97 Stratofreighters. In a demonstration of the B-52's global reach, from 16 to 18 January 1957, three B-52Bs made a
non-stop flight around the world during
Operation Power Flite, during which was covered in 45 hours 19 minutes () with several in-flight refuelings by KC-97s. The B-52 set many records over the next few years. On 26 September 1958, a B-52D set a world speed record of over a closed circuit without a payload. The same day, another B-52D established a world speed record of over a closed circuit without a payload. On 14 December 1960, a B-52G set a world distance record by flying unrefueled for ; the flight lasted 19 hours 44 minutes (). From 10 to 11 January 1962, a B-52H (60–40) set a world distance record by flying unrefueled, surpassing the prior B-52 record set two years earlier, from
Kadena Air Base,
Okinawa Prefecture, Japan, to
Torrejón Air Base, Spain, which covered . The flight passed over Seattle, Fort Worth and the Azores.
Cold War airborne nuclear alert|alt=Diagram of the route that nuclear bomb-carrying B-52s would take to enemy countries. It follows the Mediterranean Sea, and passes over Italy before turning north over the Adriatic Sea. When the B-52 entered service, the
Strategic Air Command (SAC) intended to use it to deter and counteract the vast and modernizing
Soviet Union's military. As the Soviet Union increased its nuclear capabilities, destroying or "countering" the forces that would deliver nuclear strikes (bombers, missiles, etc.) became of great strategic importance. The
Eisenhower administration endorsed this switch in focus; the President in 1954 expressed a preference for military targets over civilian ones, a principle reinforced in the
Single Integrated Operation Plan (SIOP), a plan of action in the case of nuclear war breaking out. Throughout the
Cold War, B-52s and other US strategic bombers performed airborne alert patrols under code names such as
Head Start,
Chrome Dome,
Hard Head,
Round Robin and
Giant Lance. Bombers
loitered at high altitudes near the borders of the Soviet Union to provide rapid first strike or retaliation capability in case of nuclear war. These airborne patrols formed one component of the US's nuclear deterrent, which would act to prevent the breakout of a large-scale war between the US and the Soviet Union under the concept of
Mutually Assured Destruction. Due to the late 1950s-era threat of
surface-to-air missiles (SAMs) that could threaten high-altitude aircraft, seen in practice in the
1960 U-2 incident, the intended use of B-52 was changed to serve as a
low-level penetration bomber during a foreseen attack upon the Soviet Union, as
terrain masking provided an effective method of avoiding radar and thus the threat of the SAMs. The aircraft was planned to fly towards the target at and deliver their weapons from or lower. Although never intended for the low-level role, the B-52's flexibility allowed it to outlast several intended successors as the nature of aerial warfare changed. The B-52's large airframe enabled the addition of multiple design improvements, new equipment, and other adaptations over its service life. In November 1959, to improve the aircraft's combat capabilities in the changing strategic environment, SAC initiated the
Big Four modification program (also known as
Modification 1000) for all operational B-52s except early B models. The program was completed by 1963. The four modifications were the ability to launch AGM-28 Hound Dog standoff nuclear missiles and
ADM-20 Quail decoys, an advanced electronic countermeasures (ECM) suite, and upgrades to perform the all-weather, low-altitude (below 500 feet or 150 m) interdiction mission in the face of advancing Soviet missile-based air defenses. In the 1960s, there were concerns over the fleet's capable lifespan. Several projects beyond the B-52, the
Convair B-58 Hustler and
North American XB-70 Valkyrie, had either been aborted or proved disappointing in light of changing requirements, which left the older B-52 as the main bomber as opposed to the planned successive aircraft models. On 19 February 1965, General Curtis E. LeMay testified to Congress that the lack of a follow-up bomber project to the B-52 raised the danger that, "The B-52 is going to fall apart on us before we can get a replacement for it." Other aircraft, such as the
General Dynamics F-111 Aardvark, later complemented the B-52 in roles the aircraft was not as capable in, such as missions involving high-speed, low-level penetration dashes.
Vietnam War With the escalating situation in Southeast Asia, 28 B-52Fs were fitted with external racks for 24 of the bombs under project
South Bay in June 1964; an additional 46 aircraft received similar modifications under project
Sun Bath. In March 1965, the United States commenced
Operation Rolling Thunder. The first combat mission,
Operation Arc Light, was flown by B-52Fs on 18 June 1965, when 30 bombers of the 9th and 441st Bombardment Squadrons struck a communist stronghold near the
Bến Cát District in South Vietnam. The first wave of bombers arrived too early at a designated rendezvous point, and while maneuvering to maintain station, two B-52s collided, which resulted in the loss of both bombers and eight crewmen. The remaining bombers, minus one more that turned back due to mechanical problems, continued towards the target. Twenty-seven Stratofortresses bombed a target box from between , with a little more than 50% of the bombs falling within the target zone. The force returned to
Andersen Air Force Base except for one bomber with electrical problems that recovered to
Clark Air Base, the mission having lasted 13 hours. Post-strike assessment by teams of South Vietnamese troops with American advisors found evidence that the Viet Cong had departed from the area before the raid, and it was suspected that infiltration of the south's forces may have tipped off the north because of the
South Vietnamese Army troops involved in the post-strike inspection. Beginning in late 1965, a number of B-52Ds underwent
Big Belly modifications to increase bomb capacity for
carpet bombings. While the external payload remained at 24 of or bombs, the internal capacity increased from 27 to 84 for bombs, or from 27 to 42 for bombs. The modification created enough capacity for a total of using 108 bombs. Thus modified, B-52Ds could carry more than B-52Fs. Designed to replace B-52Fs, modified B-52Ds entered combat in April 1966 flying from
Andersen Air Force Base,
Guam. Each bombing mission lasted 10 to 12 hours and included an aerial refueling by
KC-135 Stratotankers. In spring 1967, B-52s began flying from
U-Tapao Airfield in Thailand so that refueling was not required. B-52s were employed during the
Battle of Ia Drang in November 1965, notable as the aircraft's first use in a tactical support role. On 22 November 1972, a B-52D (55–110) from U-Tapao was hit by a SAM while on a raid over
Vinh. The crew was forced to abandon the damaged aircraft over Thailand. This was the first B-52 destroyed by hostile fire. The zenith of B-52 attacks in Vietnam was
Operation Linebacker II (also known as the Christmas bombings), conducted from 18 to 29 December 1972, which consisted of waves of B-52s (mostly D models, but some Gs without jamming equipment and with a smaller bomb load). Over 12 days, B-52s flew 729
sorties and dropped 15,237 tons of bombs on
Hanoi,
Haiphong, and other targets in North Vietnam. Originally 42 B-52s were committed to the war; however, numbers were frequently twice this figure. During Operation Linebacker II, fifteen B-52s were shot down, five were heavily damaged (one crashed in Laos), and five suffered medium damage. A total of 25 crewmen were killed in these losses. During the war, 31 B-52s were lost, including ten shot down over North Vietnam.
Air-to-air combat During the
Vietnam War, B-52D
tail gunners were credited with shooting down two
MiG-21 "Fishbeds". On 18 December 1972 tail gunner
Staff Sergeant Samuel O. Turner's B-52 had just completed a bomb run for Operation Linebacker II and was turning away when a
Vietnam People's Air Force (VPAF) MiG-21 approached. The MiG and the B-52 locked onto each other. When the fighter drew within range, Turner fired his quad (four guns on one mounting)
.50 (12.7 mm) caliber machine guns. The MiG exploded aft of the bomber, as confirmed by
Master Sergeant Louis E. Le Blanc, the tail gunner in a nearby Stratofortress. Turner received a
Silver Star for his actions. His B-52, tail number 56-676, is preserved on display with air-to-air kill markings at
Fairchild Air Force Base in
Spokane, Washington. On 24 December 1972, during the same bombing campaign, the B-52
Diamond Lil was headed to bomb the
Thái Nguyên railroad yards when tail gunner
Airman First Class Albert E. Moore spotted a fast-approaching MiG-21. Moore opened fire with his quad .50 caliber guns at , and kept shooting until the fighter disappeared from his scope.
Technical Sergeant Clarence W. Chute, a tail gunner aboard another Stratofortress, watched the MiG catch fire and fall away; this was not confirmed by the VPAF.
Diamond Lil is preserved on display at the
United States Air Force Academy in
Colorado. Moore was the last
bomber gunner believed to have shot down an enemy aircraft with machine guns in
aerial combat. The two B-52 tail gunner kills were not confirmed by VPAF, and they admitted to the loss of only three MiGs, all by F-4s.
Post-Vietnam War service B-52Bs reached the end of their structural service life by the mid-1960s and all were retired by June 1966, followed by the last of the B-52Cs on 29 September 1971; except for
NASA's B-52B "
008" which was eventually retired in 2004 at
Edwards Air Force Base, California. Another of the remaining B Models, "
52-005" is on display at the
Wings Over the Rockies Air and Space Museum in
Denver, Colorado. B drones A few time-expired E models were retired in 1967 and 1968, but the bulk (82) were retired between May 1969 and March 1970. Most F models were also retired between 1967 and 1973, but 23 survived as trainers until late 1978. The fleet of D models served much longer; 80 D models were extensively overhauled under the
Pacer Plank program during the mid-1970s. Skinning on the lower wing and fuselage was replaced, and various structural components were renewed. The fleet of D models stayed largely intact until late 1978 when 37 not already upgraded Ds were retired. The remainder were retired between 1982 and 1983. The remaining G and H models were used for nuclear standby ("alert") duty as part of the United States'
nuclear triad; the combination of nuclear-armed land-based missiles, submarine-based missiles, and manned bombers. The B-1, intended to supplant the B-52, replaced only the older models and the supersonic FB-111. In 1991, B-52s ceased continuous 24-hour SAC alert duty. After Vietnam, the experience of operations in a hostile air defense environment was considered. Due to this, B-52s were modernized with new weapons, equipment, and both offensive and defensive avionics. This, and the use of low-level tactics, marked a major shift in the B-52's utility. The upgrades were: • Supersonic short-range nuclear missiles: G and H models were modified to carry up to 20 SRAM missiles, replacing existing gravity bombs. Eight SRAMs were carried internally on a special rotary launcher and 12 SRAMs were mounted on two wing pylons. With SRAM, the B-52s could strike heavily defended targets without entering the terminal defenses. • New countermeasures: Phase VI ECM modification, codenamed "Rivet Ace", was the sixth major ECM program for the B-52. It improved the aircraft's self-protection capability in the dense Soviet air defense environment. The new equipment expanded signal coverage, improved threat warnings, provided new countermeasures techniques, and increased the quantity of expendables. The power requirements of Phase VI ECM also consumed most of the excess electrical capacity on the B-52G. • B-52G and Hs were also modified with an electro-optical viewing system (EVS) that made low-level operations and terrain avoidance much easier and safer. EVS system contained a low light level television (LLTV) camera and a forward-looking infrared (FLIR) camera to display information needed for penetration at lower altitudes. • Subsonic-cruise unarmed decoy: SCUD resembled the B-52 on the radar. As an active decoy, it carried ECM and other devices, and it had a range of several hundred miles. Although SCUD was never deployed operationally, the concept was developed, becoming known as the air-launched cruise missile (ALCM-A). These modifications increased weight by nearly and decreased operational range by 8–11%. This was considered acceptable for the increase in capabilities. After the fall of the Soviet Union, all B-52Gs remaining in service were destroyed in accordance with the terms of the
Strategic Arms Reduction Treaty (START). The
Aerospace Maintenance and Regeneration Center (AMRC) cut the 365 B-52s into pieces. Russia verified the completion destruction task via satellite and first-person inspection at the AMARC facility.
Gulf War and later (formerly AMARC), a desert storage facility often called the "Boneyard" at
Davis–Monthan Air Force Base, near
Tucson, Arizona. B-52 strikes were an important part of
Operation Desert Storm. Starting on 16 January 1991, a flight of B-52Gs flew from
Barksdale Air Force Base, Louisiana, refueled in the air en route, struck targets in Iraq, and returned home a journey of 35 hours and round trip. It set a record for the longest-distance combat mission, breaking the record previously held by an RAF
Vulcan bomber in 1982; however, this was achieved using forward refueling. B-52Gs operating from the
King Abdullah Air Base at Jeddah, Saudi Arabia,
RAF Fairford in the United Kingdom,
Morón Air Base, Spain, and the island of
Diego Garcia in the
British Indian Ocean Territory flew bombing missions over Iraq, initially at low altitude. After the first three nights, the B-52s moved to high-altitude missions instead, which reduced their effectiveness and psychological impact compared to the low-altitude role initially played. The conventional strikes were carried out by three bombers, which dropped up to 153 of the
M117 bomb over an area of . The bombings demoralized the defending Iraqi troops, many of whom surrendered in the wake of the strikes. In 1999, the science and technology magazine
Popular Mechanics described the B-52's role in the conflict: "The Buff's value was made clear during the Gulf War and Desert Fox. The B-52 turned out the lights in Baghdad." During Operation Desert Storm, B-52s flew about 1,620 sorties and delivered 40% of the weapons dropped by coalition forces. From 2 to 3 September 1996, two B-52Hs conducted a mission as part of
Operation Desert Strike. The B-52s struck Baghdad power stations and communications facilities with 13 AGM-86C conventional air-launched cruise missiles (CALCM) during a 34-hour, round trip mission from Andersen Air Force Base, Guam, the longest distance ever flown for a combat mission. takes off from
Andersen Air Force Base,
Guam. On 24 March 1999, when
Operation Allied Force began, B-52 bombers bombarded Serb targets throughout the
Federal Republic of Yugoslavia, including during the
Battle of Kosare. The B-52 contributed to
Operation Enduring Freedom in 2001 (Afghanistan/Southwest Asia), providing the ability to loiter high above the battlefield and provide Close Air Support (CAS) through the use of precision-guided munitions, a mission which previously would have been restricted to fighter and ground attack aircraft. In late 2001, ten B-52s dropped a third of the bomb tonnage in Afghanistan. B-52s also played a role in
Operation Iraqi Freedom, which commenced on 20 March 2003 (Iraq/Southwest Asia). On the night of 21 March 2003, B-52Hs launched at least 100 AGM-86C CALCMs at targets within Iraq.
B-52 and maritime operations The B-52 can be employed in ocean surveillance, anti-ship and mine-laying operations. For example, a pair of B-52s, in two hours, can monitor of the ocean surface. During the 2018 Baltops exercise, B-52s conducted mine-laying missions off the coast of Sweden, simulating a counter-amphibious invasion mission in the Baltic. In the 1970s, the US Navy worried that combined attacks from Soviet bombers, submarines, and warships could overwhelm its defenses and sink its aircraft carriers. After the
Falklands War, US planners feared the damage that could be created by -range missiles carried by
Tupolev Tu-22M "Backfire" bombers and -range missiles carried by Soviet surface ships. New US Navy maritime strategy in the early 1980s called for the aggressive use of carriers and surface action groups against the Soviet navy. To help protect the carrier battle groups, some B-52Gs were modified to fire Harpoon anti-ship missiles. These bombers were based in Guam and Maine in the later 1970s to support both the Atlantic and Pacific fleets. In case of war, B-52s would coordinate with tanker support and surveillance aircraft. B-52Gs could strike Soviet Navy targets on the flanks of the US carrier battle groups, leaving them free to concentrate on offensive strikes against Soviet surface combatants. Mines laid by B-52s could establish minefields in significant enemy chokepoints (mainly the
Kuril Islands and the
GIUK gap). These minefields would force the Soviet fleet to disperse, making individual ships more vulnerable to Harpoon attacks. From the 1980s, B-52Hs were modified to use a wide range of cruise missiles, laser- and satellite-guided bombs, and unguided munitions. B-52 bomber crews honed sea-skimming flight profiles that would allow them to penetrate stiff enemy defenses and attack Soviet ships. Recent expansion and modernization of the
People's Liberation Army Navy of China has caused the USAF to re-implement strategies for finding and attacking ships. The B-52 fleet has been certified to use the
Quickstrike family of naval mines using JDAM-ER guided wing kits. This weapon provides the ability to lay minefields over wide areas, in a single pass, with extreme accuracy, at a range of over . Besides this, with a view to enhancing B-52 maritime patrol and strike performance, an AN/ASQ-236 Dragon's Eye underwing pod, has also been certified for use by B-52H bombers. Dragon's Eye contains an advanced electronically scanned array radar that will allow B-52s to quickly scan vast Pacific Ocean areas. This radar will complement the Litening infrared targeting pod already used by B-52s for inspecting ships. In 2019, Boeing selected the
Raytheon to develop the new AN/APQ-188 AESA radar to replace its mechanically scanning
AN/APQ-166 attack radar; the APQ-188 is a variant of the
AN/APG-79 and also incorporates technology from the
AN/APG-82(V)1.
21st century service , in part of the
Military intervention against ISIL at
Al Udeid Air Base, in Qatar On 20 August 2003, a B-52 publicly landed in Russia for the first time, at
Zhukovsky International Airport for the
MAKS air show. In the early 1990s a B-52 "flew into Russia" as part of a "military contact visit". In August 2007, a B-52H ferrying AGM-129 ACM cruise missiles from Minot Air Force Base to Barksdale Air Force Base for dismantling was
mistakenly loaded with six missiles with their nuclear warheads. The weapons did not leave USAF custody and were secured at Barksdale. Four of 18 B-52Hs from
Barksdale Air Force Base were retired and were in the "boneyard" of 309th AMARG at
Davis-Monthan Air Force Base as of 8 September 2008. In February 2015, hull 61-0007
Ghost Rider became the first stored B-52 to return to service after six years in storage at Davis-Monthan Air Force Base. In May 2019, a second aircraft was resurrected from long-term storage in Davis-Monthan. The B-52, nicknamed "Wise Guy", had been at AMARG since 2008. It flew to Barksdale Air Force Base on 13 May 2019. It was completed in four months by a team of 13–20 maintainers from the 307th Maintenance Squadron. B-52s are periodically refurbished at USAF maintenance depots such as
Tinker Air Force Base,
Oklahoma. Even while the USAF works on the new
Long Range Strike Bomber, it intends to keep the B-52H in service until 2050, which is 95 years after the B-52 first entered service (and will be about 88 years after the last B-52H was delivered to the US Air Force), an unprecedented length of service for any aircraft, civilian or military. The USAF continues to rely on the B-52 because it remains an effective and economical heavy bomber in the absence of sophisticated air defenses, particularly in the type of missions that have been conducted since the end of the Cold War against nations with limited defensive capabilities. The B-52 has also continued in service because there has been no reliable replacement. The B-52 has the capacity to "loiter" for extended periods, and can deliver precision
standoff and
direct fire munitions from a distance, in addition to direct bombing. It has been a valuable asset in supporting ground operations during conflicts such as
Operation Iraqi Freedom. The B-52 had the highest
mission capable rate of the three types of heavy bombers operated by the USAF in the 2000–2001 period. The B-1 averaged a 53.7% ready rate, the B-2 Spirit achieved 30.3%, and the B-52 averaged 80.5%. The B-52's cost per hour of flight is more than the B-1B's cost per hour, but less than the B-2's per hour. The Long Range Strike Bomber program is intended to yield a stealthy successor for the B-52 and B-1 that would begin service in the 2020s; it is intended to produce 80 to 100 aircraft. Two competitors, Northrop Grumman and a joint team of Boeing and Lockheed Martin, submitted proposals in 2014; Northrop Grumman was awarded a contract in October 2015. On 12 November 2015, the B-52 began
freedom of navigation operations in the
South China Sea in response to
Chinese human-made islands in the region. Chinese forces,
claiming jurisdiction within a 12-mile exclusion zone of the islands, ordered the bombers to leave the area, but they refused, not recognizing jurisdiction. On 10 January 2016, a B-52 overflew parts of South Korea escorted by South Korean F-15Ks and US F-16s in response to the supposed test of a hydrogen bomb by North Korea. On 9 April 2016, an undisclosed number of B-52s arrived at
Al Udeid Air Base in Qatar as part of
Operation Inherent Resolve, part of the
military intervention against ISIL. The B-52s took over heavy bombing after B-1 Lancers that had been conducting airstrikes rotated out of the region in January 2016. In April 2016, B-52s arrived in Afghanistan to take part in the war in Afghanistan and began operations in July, proving its flexibility and precision carrying out close-air support missions. According to a statement by the US military, an undisclosed number of B-52s participated in the
US strikes on pro-government forces in eastern Syria on 7 February 2018. A number of B-52s were deployed in airstrikes against the Taliban during the
2021 Taliban offensive. In 2022, the US Air Force used a B-52 as a platform to test a
Hypersonic Air-breathing Weapon Concept (HAWC) missile. In late October 2022,
ABC News reported that the USAF intended to deploy six B-52s at
RAAF Tindal in Australia in the near future, which would include building facilities to handle the aircraft. cruise missiles during the
2026 Iran conflict, March 4, 2026 On 3 November 2024, CENTCOM confirmed an undisclosed number of B-52s from Minot Air Force Base's 5th Bomb Wing arrived in the Middle East. On 8 December 2024, CENTCOM announced that B-52s, alongside undisclosed numbers of
F-15E fighter aircraft and
A-10 attack aircraft, had participated in a number of airstrikes against over 75 Islamic State targets within Syria, following the
ousting of the al-Assad government in the country in the days prior. On 3 March 2026, CENTCOM announced that a B-52 bomber force was deployed during the
2026 Iran war, and was used to strike ballistic missile sites along with command & control posts within Iran. On 31 March, it was announced that B-52 bombers had begun flying over Iranian territory after the level of air superiority achieved was deemed adequate. ==Variants==