Blog 31: 04/24/2023: Historical Aviation: B-52 Stratofortress
B-52H of the 307th Bomb Wing, Based at Barksdale Air Force Base, Louisiana - Seen here approaching a KC-135 Stratotanker
Barksdale AFB B-52H showing off its capable ordnance with the logo of the 2nd Bomb Wing, 8th Air Force - another B-52H is airborne in the background.
(Source: U.S. Air Force photo by USAF Tech. Sgt. Robert J Horstman)
This week in historical aviation we take a look at one of, if not the most, infamous bomber and one of the most infamous military jets to ever fly! I am, of course, referring to the bomber known as the Stratofortress, of more colloquially, the B.U.F.F. - or Big Ugly Fat F***er, but officially the aforementioned Stratofortress - the B-52 Stratofortress.
B-17Gs of the 398th Bombardment Group, 8th Air Force, USAAF
Flying a bombing mission to Neumunster, Germany, on 13 April 1945, a month before the end of the war.
Originally built and designed to carry nuclear ordnance for Cold War-era deterrence missions, and first flying in 1952, entering active combat service in 1955, the B-52 has only ever dropped conventional ordnance in 68 years of combat service.
The B-52H (modern) Stratofortress is a long-range, heavy bomber that can perform a variety of missions. The bomber is capable of flying at high subsonic speeds at altitudes of up to 50,000 feet (15,166.6 meters). It can carry nuclear or precision guided conventional ordnance with worldwide precision navigation capability.
The Stratofortress has a maximum combat range of 8,000 nautical miles without aid from mid-air refueling, one of the longest ranges of any aircraft, military or no. 72 units are still well in active operation, 58 operated by regular active duty air force units - 2nd Bomb Wing and 5th Bomb Wing, both of the 8th Air Force and belonging to the Global Strike Command, the successor to Strategic Air Command during the Cold War, formed around the nucleus of the 8th Air Force. The 8th Air Force was undoubtedly the most famed and storied combatant command to emerge from the fires of World War II and notably the air war and daylight bombings over Hitler’s “Fortress Europe” primarily using B-17 heavy bombers, escorted by (first) Supermarine Spitfires, though this didn’t last long. Next, were Republic-built P-47 Thunderbolts which served till the end of the war in various roles, and finally, the North American-made P-51D Mustang, arguably the most feared fighter in Europe. The remaining 18 B-52 units are in use with USAF Reserve and their respect reserve bomber wing (namely, the 307th Bomb Wing).
While certainly large, the Boeing B-52 could still comfortably fit inside an also-Boeing built 747 Jumbo jetliner. Superior performance at high subsonic speeds and relatively low operating costs have kept them in service despite the advent of later, more advanced strategic bombers, including the Mach 2+ Convair B-58 Hustler, the canceled Mach 3 North American XB-70 Valkyrie, the variable-geometry Rockwell B-1 Lancer and the stealth Northrop Grumman B-2 Spirit, all of which, except for the B-1 Lancer and the B-2 Spirit, have been canceled and retired from service; the B-52 has outlasted them all. With the advent of the Northrop-Grumman B-21 Raider, it is safe to say the B-2s days are numbered but that is a subject for a different blog and video. After substantial upgrades, the B-52 is expected to serve until the mid-2050s or perhaps even beyond, with some Department of Defense estimates for the B-52 going into the 2080s.
ORIGINS
XB-52 prototype on flight line (X-4 Prototype in foreground; B-36 can bne seen behind). Note original tandem-seat
Note the prototype’s bubble-style tandem-seat cockpit canopy.
On 23 November 1945, Air Materiel Command (AMC) of the then-US Army Air Force issued desired performance characteristics for a new strategic bomber "capable of carrying out the strategic mission without dependence upon advanced and intermediate bases controlled by other countries". The aircraft was to have a crew of five or more turret gunners, and a six-man relief crew. It was required to cruise at 300 miles per hour (260 kn; 480 km/h) at 34,000 feet (10,000 m) with an initial optimal combat radius of 5,000 miles (4,300 nmi; 8,000 km). The armament was to consist of an unspecified number of 20 mm cannons and 10,000 pounds (4,500 kg) of bombs. On 13 February 1946, the USAF issued bid invitations for these specifications, with Boeing, Consolidated Aircraft - who built the famed B-24 Liberator heavy bomber, and Glenn L. Martin Company submitting proposals.
The final B-52 that we know and love today looked much different initially. On 5 June 1946, Boeing's Model 462, a straight-wing aircraft powered by six Wright T35 Turboprops with a gross weight of 360,000 pounds (160,000 kg) and a combat radius of 3,110 miles (2,700 nmi; 5,010 km), was declared the winner. On 28 June 1946, Boeing was issued a letter of contract for US$1.7 million to build a full-scale mockups of the new XB-52 and do preliminary engineering and testing. However, by October 1946, the USAF began to express concern about the sheer size of the new aircraft and its inability to meet the specified design requirements. In response, Boeing produced the Model 464, a smaller four-engine version with a 230,000-pound (100,000 kg) gross weight, which was briefly deemed acceptable.
Subsequently, in November 1946, the Deputy Chief of Air Staff for Research and Development, General Curtis LeMay of World War II fame, expressed the desire for a cruising speed of 400 miles per hour (350 kn; 640 km/h), to which Boeing responded with a 300,000-pound (140,000 kg) aircraft.
In December 1946, Boeing was asked to change their design to a four-engine bomber with a top speed of 400 miles per hour (350 kn; 640 km/h), range of 12,000 miles (10,000 nmi; 19,000 km), and the ability to carry a nuclear weapon; in total, the aircraft could weigh up to 480,000 pounds (220,000 kg). Boeing responded with two models powered by T35 turboprops.
The Model 464-16 was a so-called "nuclear only" bomber incapable of carrying a conventional payload with a 10,000-pound (4,500 kg) payload, while the Model 464-17 was a general purpose or conventional bomber with a 9,000-pound (4,100 kg) payload. Primarily due to the expensive and rising cost associated with purchasing and maintaining two specialized aircraft, the USAF selected Model 464–17 with the careful understanding that it could be adapted for nuclear strikes.
It was becoming obvious to the USAF that, even with the updated performance, the XB-52 would be obsolete by the time it entered production and would offer little improvement over the Convair B-36 Peacemaker, the B-52’s immediate predecessor; as a result, the entire project was postponed for at least six months.
The early development of the B-52. The Model 464-35 bore a great deal of resemblance in the Soviet Tupolev Tu-95 turboprop bomber, still in service today.
(Source: By Greg V. Goebel - http://www.vectorsite.net, Copyrighted free use, https://commons.wikimedia.org/w/index.php?curid=444660)
During this time, Boeing continued to perfect the design, which resulted in the Model 464–29 with a top speed of 455 miles per hour (395 kn; 732 km/h) and a 5,000-mile (8,000 km) range and an idea to fit new turbofan engines thereby replacing the propellers. In September 1947, the Heavy Bombardment Committee was convened to ascertain performance requirements for a nuclear bomber. Formalized on 8 December 1947, these requirements called for a rising top speed of 500 miles per hour (430 kn; 800 km/h) and an 8,000-mile (7,000 nmi; 13,000 km) range, far beyond the capabilities of the favored 464–29 variant.
DESIGN EFFORT
In May 1948, Air Materiel Command (AMC) asked Boeing to incorporate the previously discarded jet engine, with improvements in fuel efficiency into the design.
he USAF project officer who reviewed the Model 464-40 was favorably impressed, especially since he had already been thinking along similar lines. Nevertheless, the government was concerned about the high fuel consumption rate of the jet engines of the day and directed Boeing to still use the turboprop-powered Model 464-35 as the basis for the XB-52. Although he agreed that turbojet propulsion was the future, General Howard A. Craig, Deputy Chief of Staff for Materiel, was not very enthusiastic about a jet-powered B-52 since he felt that the jet engine had not yet progressed sufficiently to permit skipping an intermediate turboprop stage. However, Boeing was encouraged to continue turbojet studies even without any expected commitment to jet propulsion.
Side-upper view of the upgraded and redesigned YB-52 after the Dayton meeting.
Note the still-in-place tandem cockpit, thinner fuselage, and lengthened wings as well as the addition of twinned jet engines and the signature pylons and nacelles.
On Thursday, 21 October 1948, Boeing engineers George S. Shearer, Art Carlsen, and Vaughn Blumenthal presented the design of a four-engine turboprop bomber to the chief of bomber development, Colonel Pete Warden was disappointed by the projected aircraft and asked if the Boeing team could produce a proposal for a four-engine turbojet bomber. Joined by Ed Wells, Boeing's vice-president of engineering, the engineers worked that night in The Hotel Van Cleve in Dayton, Ohio, redesigning Boeing's propeller-driven proposal as a four-engine turbojet bomber. On Friday, Colonel Warden looked over the information and asked for a better design. Returning to the hotel, the Boeing team was joined by Bob Withington and Maynard Pennell, two top Boeing engineers who were in town on other business and lent their expertise.
By late Friday night, Oct. 22, the engineers had laid out what was an essentially new airplane. The new design (464-49) built upon the basic layout of the B-47 Stratojet with 35-degree swept wings, eight engines paired in four underwing nacelles, coupled with bicycle landing gear with wingtip outrigger wheels. The same basic design exists to this day.
During ground testing on 29 November 1951, the XB-52's pneumatic system failed during a full-pressure test; the resulting explosion severely damaged the trailing edge of the wing, necessitating considerable repairs. The YB-52, the second XB-52 modified with additional operational equipment, first flew on 15 April 1952. A 2-hour, 21-minute proving flight from Boeing Field, King County, in Seattle, Washington, to Larson Air Force Base was undertaken with Boeing test pilot Johnston and USAF Lieutenant Colonel Guy M. Townsend. Boeing Field is still Boeing’s primary test facility.
UPGRADES - 2022, 2023, Beyond
The B-1 Lancer and B-2 Spirit are directly compared here to the B-52 because not only are they contemporaries, they also serve alongside the B-52 Stratofortress.
A proposed variant of the B-52H, was the EB-52H, which would have consisted of 16 modified and augmented B-52H airframes with additional electronic jamming capabilities. This was largely abandoned.
B-52 (testbed model) over Seattle
Designed to investigate structural failures. Shown here with a missing vertical stabilizer.
In July 2013, the USAF began a fleet-wide technological upgrade of its B-52 bombers called Combat Network Communications Technology (CONECT) to modernize electronics, communications technology, computing, and avionics on the flight deck. CONECT upgrades include software and hardware such as new computer servers, modems, radios, data-links, receivers, and digital workstations for the crew. One update is the AN/ARC-210 Warrior beyond-line-of-sight software programmable radio able to transmit voice, data, and information in-flight between B-52s and ground command and control centers, allowing the transmission and reception of data with updated intelligence, mapping, and targeting information; previous in-flight target changes required copying down coordinates. The ARC-210 allows machine-to-machine transfer of data, useful on long-endurance missions where targets may have moved before the arrival of the B-52. CONECT upgrades will cost US$1.1 billion overall and take several years. Funding has been secured through congress for 30 B-52s; the USAF hopes for 10 CONECT upgrades per year, but the rate has yet to be decided for annual Department of Defense budgetary considerations.
WEAPONS / OVERALL ARMAMENT UPGRADES
B-52D Tailgunner Position
In later models, the tail gunner was moved from the traditional position to the forward crew compartment, before being removed altogether. The 4x 50. caliber tailguns did score an aerial victory. This model is on display at the USAF Academy in Colorado Springs, CO.
(Source: https://web.archive.org/web/20161028224034/http://www.panoramio.com/photo/105122342)
Weapons upgrades include the 1760 Internal Weapons Bay Upgrade (IWBU), which gives a 66 percent increase in weapons payload using a digital interface (MIL-STD-1760) and rotary launcher, far more than the initial “Big Belly” upgrade all B-52s underwent decades before. The IWBU is expected to cost roughly $313 million USD in 2022 dollars. The 1760 IWBU will allow the B-52 to carry eight JDAM 2,000-pound (910 kg) bombs, AGM-158-JASSM-ER cruise missile and the ADM-160C-MALD-J decoy missiles internally. All 1760 IWBUs should be operational by October 2017. Two bombers will have the ability to carry 40 weapons in place of the 36 that three B-52s can carry. The 1760 IWBU allows precision-guided missiles or bombs to be deployed from inside the weapons bay; the previous aircraft carried these munitions externally on the wing hardpoints. This increases the number of guided weapons (Joint Direct Attack Munitions or JDAM) a B-52 can carry and reduces the need for guided bombs to be carried on the wings. The first upgrade phase will allow a B-52 to carry twenty-four GBU-38 500-pound guided bombs or twenty GBU-31 2,000-pound bombs, with later phases accommodating the JASSM and MALD family of missiles.
The Conventional Enhancement Modification (CEM) program gave the B-52H a more comprehensive conventional weapons capability, adding the modified underwing weapon pylons used by conventional-armed B-52Gs, Harpoon and Have Nap, and the capability to carry new-generation weapons including the Joint Direct Attack Munition (JDAM) and Wing Corrected Dispenser Munition guided bombs, the AGM -154 glide bomb and the AGM-158 JASSM missile. The CEM program also introduced new radios, integrated Global Positioning System into the aircraft's navigation system, and replaced the under-nose FLIR with a more modern unit.
Forty-seven (47) B-52Hs were modified under the CEM program by 1996, with 19 more by the end of 1999. This accounts for virtually the entire B-52 fleet in the USAF arsenal.
Early on, by around 2010, U.S STRATCOM, or Strategic Command, stopped assigning B61 and B63 nuclear gravity bombs to the B-52, and later listed only the B-2 Spirit stealth bomber (soon the B-21 Raider) as tasked with delivering strategic nuclear bombs in budget requests. Nuclear gravity bombs were removed from the B-52's capabilities because it is no longer considered survivable enough to penetrate modern air defenses, instead relying on nuclear cruise missiles and focusing on expanding its conventional strike role. The 2019 "Safety Rules for U.S. Strategic Bomber Aircraft" manual subsequently confirmed the removal of B61-7 and B83-1 gravity bombs from the B-52H's approved weapons configuration.
While the Rockwell B-1 Lancer, now serving alongside the B-52, has a larger theoretical maximum payload of 75,000 pounds (34,000 kg) compared to the B-52's 70,000 pounds (32,000 kg), the bombers are rarely able to carry their full loads. The most the B-52 carries is a full load of AGM-86Bs totaling 62,660 pounds (28,420 kg). The B-1 Lancer has the internal weapons bay space to carry more GBU-31 JDAMs and JASSMs, but the B-52 was upgraded with the conventional rotary launcher can carry more of other JDAM variants. In the end, the question for mission commanders, was what type of ordnance they desired more of and how fast they wanted it delivered.
In addition to carrying additional quantities of smart bombs, moving them internally from the wings reduces drag and achieves a 15 percent reduction in fuel consumption. As of late 2022, The US Air Force Research Lab at Wright-Patterson Air Force Base, Dayton, Ohio is investigating defensive laser weapons for the B-52. AGM-183A Air-Launched Rapid Response (ARRW) hypersonic missile and the future Long-Range Standoff (LRSO) nuclear-armed air-launched cruise missile will join the B-52 inventory in the future for use or deterrence operations.
B-17G/F Flying Fortress, B-29B Superfortress, and B-52G Stratofortress flying together in formation at the 2017 Barksdale Air force Base Air Show, Louisiana.
The B-52 is due to receive a range of upgrades alongside a planned engine retrofit. These upgrades aim to modernize the sensors and displays of the B-52. They include the new APG-79B Active Electronically-scanned array radar, replacing older mechanically scanned arrays, the streamlining of the nose and deletion of blisters in the fuselage housing the forward-looking infrared/electro-optical viewing system. The upgrades will also include improved communication systems, new pylons, new cockpit displays and the deletion of one crew station. The changes will likely be enough to warrant changing the designation of the B-52H to B-52J or B-52K.
DESIGN OVERVIEW & AVIONICS
The B-52 shared many technological similarities with the preceding B-47 Stratojet strategic bomber. The two aircraft used the same basic design, such as swept wings and podded jet engines, and the cabin included the crew ejection systems. On the B-52D, the pilots and electronic countermeasures (ECM) operator ejected upwards, while the lower deck crew ejected downwards; until the B-52G, the gunner had to jettison the tail gun to bail out. The tail gunner in early model B-52s was located in the traditional location in the tail of the plane, with both visual and radar gun targeting and operating systems; in later models, the gunner was moved to the front of the fuselage, with gun operations carried out by radar alone, much like the B-58 Hustler's tail gun system.
The wings of the bomber were modified by 1964 under ECP 1050. This was followed by a fuselage skin and longeron replacement (the ECP 1185 upgrade package) in 1966, and the B-52 Stability Augmentation and Flight Control program (ECP 1195) in 1967.
Fuel leaks due to deteriorating clamps continued to plague all variants of the B-52. To this end, all aircraft variants were subjected to Blue Band (1957), Hard Shell (1958), and finally QuickClip upgrade in 1958, all of which were upgrade programs. The latter fitted integral safety straps that prevented catastrophic loss of fuel in case of clamp failure.
Early active duty 1960s-era B-52 painted in anti-flash white
A commonly-used technique used during the Cold War, the white paint was believe to have anti-nuclear and anti-radiation effects. This was demonstrably false as history and science has shown, but the psychological effects on pilots and crews were very real indeed.
(Source: By US Government, Public Domain, https://commons.wikimedia.org/w/index.php?curid=1671356)
The lower-deck of the B-52G
This area is also known colloquially as the Battle Station
B-52s built prior to the G models had very small ailerons with a short span that was approximately equal to their chord. These "feeler ailerons" were used to provide feedback forces to the pilot's control yoke and to fine-tune the roll axes during delicate maneuvers such as aerial refueling. Due to twisting of the thin main wing, conventional outboard flap-type ailerons would lose authority and therefore could not be used. In other words, aileron activation would cause the wing to twist, undermining roll control. Six spoilerons on each wing are responsible for the majority of roll control. The late B-52G models eliminated the ailerons altogether and added an extra spoileron to each wing. Partly because of the lack of ailerons, the more modern B-52G and H models were more susceptible to Dutch roll. Spoilerons can be thought of as additional stabilizers for large, heavy military aircraft they will almost never be seen on civilian aircraft.
The IBM AP-101 computer, also used on the Rockwell B-1 Lancer supersonic bomber, the B-52’s supersonic counterpart, and NASA’s Space Shuttle orbiter was the B-52's main mission and avionics computer onboard. In 2007, the LITENING targeting pod was fitted, which increased the effectiveness of the aircraft in the attack of ground targets with a variety of standoff weapons, using laser guidance, a high-resolution forward-looking infrared sensor (FLIR), and a CCD Camera used to obtain target imagery.
ENGINES
The eight engines of the B-52 are paired in pods and suspended by four pylons beneath and forward of the wings' leading edge. The careful arrangement of the pylons also allowed them to work as wing fences and delay the onset of stall.
The first two prototypes, XB-52 and YB-52, were both powered by experimental Pratt & Whitney YJ57-P3 turbojet engines of 8,700 pounds-force (39 kN) of static thrust each.
The B-52A models were equipped with Pratt & Whitney J57-P-1W turbojets, providing a dry thrust of 10,000 pounds-force (44 kN) which could be increased for short periods to 11,000 pounds-force (49 kN) with water-injection. The water was carried in a 360 US gallons (1,400 L) tank in the rear fuselage. B-52B, C, D and E models were equipped with Pratt & Whitney J57-P-29W, J57-P-29WA, or J57-P-19W series engines all rated at 10,500 lbf (47 kN). The B-52F and G models were powered by Pratt & Whitney J57-P-43WB turbojets, each rated at 13,750 pounds-force (61.2 kN) static thrust with water injection.
On the 9th of May 1961, the B-52H began to be delivered to the USAF with cleaner burning and quieter Pratt & Whitney TF33-P3 turbofan engines with a maximum thrust of 17,100 pounds-force (76 kN).
Engine Retrofit
In a study for the USAF in the mid-1970s, Boeing investigated replacing the engines, changing to a new wing, and other improvements to upgrade B-52G/H aircraft as an alternative to the B-1A Lancer, Rockwell’s initial developmental bomber, then in development.
In 1996, Rolls-Royce and Boeing jointly proposed fitting each B-52 with four leased Rolls-Royce RB-211 engines. This would have involved replacing the eight Pratt & Whitney TF33 engines (total thrust 136,000 lbf ([600 kN]) with four RB211-535E4 engines (total thrust 172,400 lbf (767 kN)), which would increase range and reduce fuel consumption. However, the problem arose when a USAF analysis in 1997 concluded that Boeing's estimated savings of US$4.7 billion would not be realized and that reengining would instead cost US$1.3 billion more than keeping the existing engines, citing significant up-front procurement and re-tooling expenditure.
General Electric CF34-CB1 Engine
CF34, originally designed for Canadair regional jets, retooled for military use under the CERP program for the USAF.
(Source: By Gleb Osokin - Russian AviaPhoto Team - Gallery page http://www.airliners.net/photo/UTair-Aviation/Canadair-CL-600-2B19-Regional/2213397/LPhoto http://cdn-www.airliners.net/aviation-photos/photos/7/9/3/2213397.jpg, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=28640630)
The Up-and-Coming Rolls-Royce F130 Turbofan engine
(rearview) featured at Templehof Aviation Museum, Berlin, Germany
(Source: By -jkb- - https://clippingmagic.com/images/37774802/edit/rgkijmd9rei6ce5em64mnlbg2b50nh6ltg42892jm0i6gqgo5vn0, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=70143647)
GE Passport AKA EBRACE Engine, developed for large business jets.
(Source: By Matti Blume - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=79086417)
The USAF's 1997 rejection of reengining was subsequently disputed in a Defense Science Board (DSB) report in 2003. The DSB urged the USAF to re-engine the aircraft without delay, saying doing so would not only create significant cost savings but reduce greenhouse gas emissions and increase aircraft range and endurance; these conclusions were in line with the conclusions of a separate Congress-funded study conducted in 2003. Criticizing the USAF cost analysis, the DSB found that among other things, the USAF failed to account for the cost of aerial refueling; the DSB estimated that aerial refueling cost $17.50 per US gallon, whereas the USAF had failed to account for the cost of delivering the fuel, and so had only priced fuel at $1.20 per US gallon. A significant oversight, to be sure. As the 2020s dawned, the USAF released its request for proposals for 608 commercial engines plus spares and support equipment, with the plan to award the contract in May 2021. This Commercial Engine Reengining Program (CERP) saw General Electric propose its CF34-CB1 and Passport turbofans (pictured), Pratt & Whitney its PW800, and Rolls-Royce its F130 turbofan. Unlike the previous re-engine proposal which also involved reducing the number of engines from eight to four, the F130 re-engine program maintains eight engines on the B-52. Although four-engine operation would be more efficient, retrofitting the airframe to operate with only four engines would involve additional changes to the aircraft's systems and control surfaces (particularly the narrow rudder), thereby increasing the time, cost, and complexity of the project. B-52Hs upgraded with Rolls-Royce F130 turbojet engines will be redesignated as "B-52Js" and will debut in late 2025.
OPERATIONAL HISTORY
With the escalating situation in Southeast Asia, 28 B-52Fs were fitted with external racks for 24 of the 750 pounds (340 kg) 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 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. Beginning in late 1965, a number of B-52Ds underwent Big Belly modifications to increase bomb capacity for carpet bombings.
Operation Chrome Dome travel route
B-52s would be airborne at all times.
(Source: Emt147 at English Wikipedia. Transferred from en.wikipedia to Commons by Zscout370 using CommonsHelper., CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=15172330)
Op: Chrome Dome Northly Route from Sheppard Air Force Base, Texas
USA to USSR through Canada route
Operation Chrome Dome was a Cold War-era deterrence mission, flown for almost a decade from 1960 to 1968 in which B-52 aircraft armed with thermonuclear warheads remained on continuous airborne alert and flew routes to points on the Soviet Union's border.
These airborne patrols, including Chrome Dome and other sub-missions, formed one key 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 or MAD. Due to the late 1950s-era threat of increasingly powerful surface-to-air missiles (SAMs) that could threaten high-altitude aircraft, seen in practice in the 1960 Gary Powers 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 (using terrain to mask the signature of the aircraft in question) provided an effective method of avoiding radar (which typically only functioned at moderate to high-altitudes) and thus the threat of the SAMs.
As a result, the new tactic was that the B-52 aircraft was planned to fly towards the target at 400–440 mph (640–710 km/h) and deliver their weapons from just 400 ft (120 m) or lower in total altitude. 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.
B-52F Dropping Bombs Over Vietnam
Operation Rolling Thunder - 1965
(Source: By -jkb- - https://clippingmagic.com/images/37774802/edit/rgkijmd9rei6ce5em64mnlbg2b50nh6ltg42892jm0i6gqgo5vn0, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=70143647)
POST-VIETNAM & LATER
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, with the exception of NASA’s lone experimental model. which went on to serve until 2004 when it was retired at Edwards Air Force Base in California. 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 bomber 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 and serve until this day as newer H models. 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 by the 1980s.
B-52H modified to carry two D-21 Drone aircraft, photo taken by KC-135 after refueling.
COMBAT EXPERIENCE UPGRADES
The remaining G and H models were continually upgraded and used for nuclear standby ("alert") duty as part of the United States' nuclear tried; the combination of nuclear-armed land-based missiles (USAF), submarine-based missiles (SLBM - US Navy), and manned bombers (USAF. The B-1, intended to supplant the B-52, replaced only the older models and the supersonic FB-111 which had outlived its usefulness. The F-111 would go on for a time as the EF-111 Raven electronic warfare aircraft. In 1991, B-52s ceased continuous 24-hour SAC alert duty, before Strategic Air Command (SAC) was reorganized as Global Strike Command.
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 consecutive experience-based 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 12x 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 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 24,000 pounds (11,000 kg) and decreased operational range by 8–11%. This was considered acceptable for the increase in capabilities.
B-52Gs Cut into Pieces at the 309th Aerospace Maintenance and Regeneration Group (AMARG), at Davis-Monthan Air Force Base, Arizona.
However, in accordance with the START Treaty - Strategic Arms Reduction Treaty, the B-52Gs were largely destroyed after the fall of the Soviet Union in 1991, after the Gulf War action.
GULF WAR
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 14,000 miles (23,000 km) round trip. It set a record for the longest-distance combat mission, breaking the record previously held by an RAF Vulcan bomber in 1982 during the Falkland Islands War; however, this was only achieved using forward refueling.
B-52Gs operating from various forward bases across southern Europe and the Middle East lew 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 750 lb (340 kg) M117 bomb over an area of 1.5 by 1 mi (2.4 by 1.6 km). The bombings demoralized the defending Iraqi troops, many of whom surrendered in the wake of the strikes.
According to an issue of Popular Mechanics in 1991, “The B-52 alone turned out the lights in Baghdad." To emphasize this, during Operation Desert Storm, B-52s flew about 1,620 sorties and delivered 40% of the weapons dropped by coalition forces.
Since the mid-1990s, the B-52H has been the only variant remaining in military service, though as stated, it is slated for upgrades.
The B-52 can be highly effective for ocean surveillance and can assist the Navy in anti-ship and mine-laying operations. For example, a pair of B-52s, in two hours, can monitor 140,000 square miles (360,000 square kilometers) of the ocean surface. During the 2018 Baltops exercise B-52s conducted mine-laying missions off the coasts of Sweden, simulating a counter-amphibious invasion mission in the Baltic.
After the Falklands War, US planners feared the damage that could be created by 200-mile (170 nmi; 320 km)-range missiles carried by then-Soviet Tupolev Tu-22M "Backfire" bombers and 250-mile (220 nmi; 400 km)-range missiles carried by Soviet surface ships. New US Navy's 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-52G 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 by AWACS and Navy planes. 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 down by B-52s could establish minefields in significant enemy chokepoints (mainly the Kuril Islands and the GIUK - Greenland, Iceland, UK Gap -Gap). These minefields would force the Soviet fleet to disperse, making individual ships more vulnerable to Harpoon attacks.
Recent expansion and modernization of the People’s Liberation Army Navy of China have 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 down minefields over wide areas, in a single pass, with extreme accuracy, all while standing-off over 40 miles (35 nmi; 64 km) away. 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, so finding and sinking enemy ships will be easier for them. This radar will complement the LITENING infrared targeting pod already used by B-52s for inspecting ships.
B-52H taking off from Anderson Air Force Base, Guam. 2nd Bomb Wing.
Source: Trevor MacInnis at English Wikipedia. - Transferred from en.wikipedia to Commons by Rcbutcher using CommonsHelper., Public Domain, https://commons.wikimedia.org/w/index.php?curid=17935565)
21ST CENTURY SERVICE
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. It serves alongside the soon -to-be-retired B-2 Spirit, the soon-to-be-introduced B-21 Raider, the tried-and-true Rockwell (Boeing) B-1 Lancer.
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 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. Lockheed was awarded the initial contract in 2015. But that is a story for another time.
According to the press statement by the United States Air Force itself - Public Relations Department, “In a conventional conflict, the B-52 can perform strategic attack, close-air support, air interdiction, offensive counter-air and maritime operations.
In two hours, two B-52s can monitor 140,000 square miles (364,000 square kilometers) of ocean surface.
All B-52s can be equipped with two electro-optical viewing sensors, a forward-looking infrared and advanced targeting pods to augment targeting, battle assessment and flight safety, further improving its combat ability.
Pilots wear night vision goggles, or NVGs, to enhance their vision during night operations. Night vision goggles provide greater safety during night operations by increasing the pilot's ability to visually clear terrain, increasing the peacetime and combat situational awareness of the aircrew and improving their ability to visually acquire other aircraft.
B-52s are equipped with advanced targeting pods. Targeting pods provide improved long-range target detection, identification and continuous stabilized surveillance for all missions, including close air support of ground forces. The advanced targeting and image processing technology significantly increases the combat effectiveness of the B-52 during day, night and less than ideal weather conditions when attacking ground targets with a variety of standoff weapons (e.g., laser-guided bombs, conventional bombs and GPS-guided weapons).
The use of aerial refueling gives the B-52 a range limited only by aircrew endurance. It has an unrefueled combat range in excess of 8,800 miles (14,080 kilometers).”
General Characteristics
Primary Function: Heavy bomber
Contractor: Boeing Military Airplane Co.
Power plant: Eight Pratt & Whitney engines TF33-P-3/103 turbofan
Thrust: Each engine up to 17,000 pounds
Wingspan: 185 feet (56.4 meters)
Length: 159 feet, 4 inches (48.5 meters)
Height: 40 feet, 8 inches (12.4 meters)
Weight: Approximately 185,000 pounds (83,250 kilograms)
Maximum Takeoff Weight: 488,000 pounds (219,600 kilograms)
Fuel Capacity: 312,197 pounds (141,610 kilograms)
Payload: 70,000 pounds (31,500 kilograms)
Speed: 650 miles per hour (Mach 0.84)
Range: 8,800 miles (7,652 nautical miles)
Ceiling: 50,000 feet (15,151.5 meters)
Armament: Approximately 70,000 pounds (31,500 kilograms) mixed ordnance—bombs, mines and missiles. (Modified to carry air-launched cruise missiles)
Crew: Five (aircraft commander, pilot, radar navigator, navigator and electronic warfare officer)
Unit Cost: $84 million (fiscal 2012 constant dollars)
Initial operating capability: April 1952
Inventory: Active force, 58 (test including NASA, 4); ANG, 0; Reserve, 18
ANG refers to Air National Guard
USAF B -52H, 307th Bomb Wing, flying in formation with 2 F-35 Lightning IIs over the Atlantic Ocean
From Prototype hopeful replacement to conventional bomber to variable mission specialist and Psy-Ops professional, the B-52 is indeed the ultimate close-support weapon.
