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THE 456th FIGHTER INTERCEPTOR SQUADRON |
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T PROTECTORS OF S. A. C. |
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The History Of The Boeing B-52 |
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The Boeing B-52 'Stratofortress"
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Since it became operational in 1955, the B-52 has been the main long-range heavy bomber of the Strategic Air Command. It first flew on Apr. 15, 1952. Nearly 750 B-52s were built when production ended in Oct. 1963, of which 170 were -Ds. The -Ds were modified to carry conventional bombs and Quail decoy missiles.
The B-52 has set many records in its 25-plus years of service. On Jan. 18, 1957, three B-52Bs completed the world's first non-stop round-the-world flight by jet aircraft, lasting 45 hours and 19 minutes with only three aerial refueling en route. It was also a B-52 that made the first airborne hydrogen bomb drop over Bikini Atoll on May 21, 1956. In June 1965, B-52s entered combat when they began flying missions in Southeast Asia (SEA). By Aug. 1973, they had flown 126,615 combat sorties with 17 B-52s lost to enemy action.
The aircraft on display saw extensive service in SEA and was severely damaged (See below) by an enemy surface-to-air missile (SAM) on April 9, 1972. In Dec. 1972, after being repaired, it flew four additional missions over North Vietnam. Transferred from the 97th Bomb Wing, Blytheville AFB, Ark., this aircraft was flown to the USAF Museum in Nov. 1978.
SPECIFICATIONS
Span: 185 ft.
Length: 156 ft. 6 in.
Height: 48 ft. 4 in.
Weight: 450,000 lbs. max.
Armament: Four .50-cal. machine guns in tail plus bombs--nuclear or up to 60,000 lbs. of conventional
Engines: Eight Pratt & Whitney J57s of 12,100 lbs. thrust ea. with water injection
Cost: $7,000,000PERFORMANCE
Maximum speed: 638 mph.
Cruising speed: 526 mph.
Range: 8,338 miles unrefueled
Service Ceiling: 49,400 ft.
Pratt & Whitney J57 Turbojet
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The J57 production engine was the world's first jet engine to develop 10,000 lbs. thrust. It evolved from the T45 turboprop engine designed for the XB-52 program. As advances in the B-52 design dictated greater power requirements, the turboprop concept was discarded and the wasp-waisted J57 turbojet was developed. The J57 featured a dual-rotor axial-flow compressor which allowed low fuel consumption over a wide operating range and improved the sluggish acceleration previously characteristic of jet engines.
The same year that production began, 1953, America's highest aviation honor, the Collier Trophy, was awarded for the design and development of this engine. Using a J57, the North American YF-100A became the world's first fighter aircraft to reach supersonic speed in level flight, on its maiden flight on May 25, 1953. Later versions of the J57 and its commercial equivalent, the JT3, reached the 18,000 lbs. thrust level with an afterburner. When production ended in 1970, more than 21,000 of these engines had been built. In addition to the B-52 and F-100, the J57 (or JT3) powered the Vought F8U; Douglas F4D, F5D, and A3D; Boeing 707 and 720; Douglas DC-8; and numerous USAF aircraft including the KC-135, F-101A, and F-102A.
The J57 on display is a YJ57-P-3, the first series to go into production. Rated at 8,700 lbs. thrust, it served as the prototype for the higher-powered engines later used in B-52s. P-3s were also used in testing the Northrop XSM-62 Snark missile and the Convair XB-60, an all-jet development of the B-36. This engine was the 16th of the 95 P-3s built and was used in XB-52 testing.
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Battle Damage Report B-52D S/N 56-665 |
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"There are approximately 56 holes causing extensive damage to skin structures at the following locations: fuselage, left and right wings, nose radome, left aft wheel door, vertical (stabilizer), left and right horizontal stabilizers, and the left and right drop tanks."
(damage indicated by yellow dots)"Internal damage is as follows: seven holes in forward body (fuel) tank cell #1; 70 holes in the forward body (fuel) tank cell #2; 40 holes in the mid-body (fuel) tank cell #1; one hole in the mid-body (fuel) tank cell #2; 51 holes in the aft body (fuel) tank cell #1; and numerous holes in the #1 cell of the water tank. Both ram air ducts have numerous holes and dents."
(damage indicated by red dots)"Flak hit the IFR (in-flight refueling) manifold but did not exit. (The) fuel vent tube is full of buckshot-size holes, (the) astro tracker is damaged beyond repair, and (the) static port (at) Sta 1015.0. W.L. 169.1 is also damaged."
(damage indicated by blue dots)"The #1 and #3 engines will require replacement. Aircraft hours: 9,690.9"
(damage indicated by black dots)Courtesy Of The Air Force Museun
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The Origin & Preliminary Development Of The B-52 |
By Joe Baugher
The B-52 Stratofortress has been the backbone of the Air Force's manned bomber strategic deterrent for the last 35 years. The B-52 entered service with the Strategic Air Command in 1955, and by 1958 it represented the most important component of America's strategic deterrent. At peak strength in 1963, SAC operated 650 B-52s, divided up among 42 squadrons at 38 different air bases. However, intercontinental ballistic missiles assumed a greater role in the strategic deterrent, but the B-52 remained important even after missiles had assumed the primary responsibility for the deterrent. The B-52 had been designed for the strategic nuclear bombardment role, but it was to assume an important conventional role in two wars--the Southeast Asian War of 1965-1972 and Desert Storm of 1991. The Stratofortress has been periodically been upgraded over the years to make it a more capable weapons delivery platform, and had swapped roles from high-altitude nuclear bomber to low-level strike aircraft and cruise-missile carrier.
By now, budgetary limitations imposed by the end of the Cold War as well as treaty restrictions have relegated most of the B-52 fleet to the bone yards or to museums, and many of them have been scrapped. However the B-52H version still remains in service in substantial numbers and will remain so well into the 21st century.
The development of the B-52 can be said to begin back in June of 1945, at a time when the war in the Pacific was still going on. Assuming that the war in the Pacific would soon be over, the Army Air Forces directed the Air Material Command to begin the formalization of requirements for the characteristics of a new generation of postwar bombers. The seizure of forward island bases for B-29 operations against Japan at the cost of so much blood and treasure being quite recently in mind, chief among the requirements for a postwar long-range strategic bomber would be the ability to carry out its mission without the need for the reliance on advanced or intermediate bases controlled by other countries.
On November 23, 1945, with the Pacific War now over, a series of specifications were issued calling for a bomber with an operating radius of 5000 miles and a speed of 300 mph at 34,000 feet. The crew was to be five, plus gunners for an undetermined number of 20-mm cannon turrets. A 10,000 pound bomb load was specified, as well as provisions for a 6-man relief crew. What was sought was fundamentally a second-generation intercontinental bomber to replace the Convair B-36, which had still not yet made its maiden flight.
On February 13, 1946, the new bomber project was submitted to the aviation industry, with invitations to bid on the military characteristics laid down in the November specification. Three manufacturers-the Boeing Airplane Company, the Glenn L. Martin Company, and the Consolidated Vultee Aircraft Corporation--submitted cost quotations and preliminary design data.
The Boeing proposal was known by the company as the Model 462. It looked a lot like a scaled-up B-29, being a fairly conventional monoplane with a shoulder-mounted straight wing with a span of 221 feet and an area of 3250 square feet. The circular-section fuselage was 161 feet 2 inches long. Power was to be provided by six Wright XT35 Typhoon turboprop engines, each offering 5500 shaft horsepower and driving six-bladed propellers. The decision to use turboprop engines rather than pure jets was a result of the fact that the jet engines of the day were notorious fuel hogs and would make it difficult if not impossible to meet the range requirements. The four main wheels of the nose wheel undercarriage each retracted separately into the four inner engine nacelles. Gross weight was 360,000 pounds.
Although the Model 462 fell far short of meeting the range requirement, Boeing was informed on June 5, 1946 that it had won the competition. In mid-June, the Boeing design was assigned the designation XB-52. The letter contract issued to Boeing on June 28 (W-33-03A-ac-15065) asked for a full-scale mockup of the XB-52, plus preliminary design engineering, and the supplying of test data.
In October of 1946, less than three months after Boeing had received the Letter Contract, the USAAF was already beginning to experience misgivings about the XB-52. It was concluded that the aircraft that had been proposed by Boeing was simply too large and expensive, that it offered few performance advantages over the B-36, and that it did not offer very much in the way of growth potential. Maj Gen Earle E. Partridge, assistant chief of Air Staff for operations, bluntly pointed out to Boeing that the Model 462 simply did not meet the range requirement.
Undaunted, Boeing went back to the drawing board and came up with the Model 464. It was a much smaller version of the Model 462, with only four Wright XT-35 turboprops and a gross weight of only 230,000 pounds.
Maj Gen Laurence C. Craigie, chief of the USAAF Engineering Division, recommended that the new Model 464 design be adopted. However, in November of 1946, General Curtis E. LeMay, then Deputy Chief of Air Staff for Research and Development, pointed out that the Model 464 was still not good enough. He thought that the future B-52 should have a higher cruising speed as well as a longer range.
In December, the USAAF requested that a study be carried out for a four-engine bomber with a range of 12,000 miles, a cruising speed of 400 mph, and the ability to carry and drop the atomic bomb. Boeing came up with two separate proposals--Models 464-16 and 464-17. Both were still powered by four Wright XT-35 turboprops, but these engines now promised a significantly higher power output than was offered for the earlier 464 version, and a better performance was anticipated. The new proposals were also significantly larger and heavier than the earlier 464 version. Gross weight was now estimated at 400,000 pounds, wingspan was 205 feet, wing area was 3000 square feet, and length was 156 feet. Effective range was extended by the use of large external tanks underneath the outer wings. Top speed was estimated at 440 mph at 35,000 feet.
The difference between the two models was that the 464-16 was a "specialized" version (i.e. intended for the delivery of nuclear weapons) that could carry only a 10,000 pound bomb load over a long range and the 464-17 was optimized for conventional warfare and was capable of carrying a bomb load as high as 90,000 pounds over a much more restricted range.
The USAAF clearly could not afford to fund both projects simultaneously, and they opted for the conventional-warfare Model 464-17. Apart from the range, the Model 464-17 appeared to meet the requirements. However, with the advent of mid-air refueling, the shortfall in range did not now appear to be all that critical a disadvantage. However, General LeMay was still not happy, since he felt that this version of the XB-52 would still be too large and costly--perhaps limiting procurement to only 100 aircraft. To make matters worse, General Cragie was now solidly against the project, claiming that it offered little improvement over the B-36, and that the B-52 would likely be obsolete before it could enter service. Consequently, the Model 464-17 was shelved.
That would ordinarily have been the end of the line for the B-52, but General LeMay urged caution, and suggested a 6-month grace period before the final decision on the future of the B-52 could be made.
Boeing designers went back to work again, and went through a succession of designs during the first few months of 1949, before they settled on the Model 464-29. This version had the same four XT-35 turboprops of previous versions, but now featured a sharply tapered wing with 20 degrees of sweepback. An extended dorsal fin was provided. The wingspan remained at 205 feet and the weight at 400,000 pounds. A major change was the adoption of a centerline landing gear underneath the fuselage similar to that fitted to the B-47 but with forward and aft units much closer together, plus a set of outrigger wheels which retracted into the outer engine nacelles. The estimated maximum speed was 445 mph.
In the latter half of 1947, the Air Force was still looking for more effective means of delivering nuclear weapons. A Heavy Bombardment Committee was established to explore alternatives. Speed and altitude were found to be crucial qualities required of an aircraft capable of delivering the atomic bomb. This was particularly true when the bomber reached the combat zone. A new set of requirements was drawn up, calling for a special-purpose bomber with an 8000-mile range and a 550-mph cruising speed. These new requirements were officially issued on December 8, 1947, although at that time the cruising speed requirement was lowered to only 500 mph.
Under the new set of requirements, both the range and speed of the Model 464-29 would clearly be inadequate. During the winter of 1947-48 things looked so unpromising that the entire B-52 project was on the verge of cancellation. On December 11, 1947, the Air Materiel Command had actually been directed to cancel the Boeing contract, but a protest from Boeing chairman William M. Allen persuaded Secretary of the Air Force Stuart Symington to grant a stay of execution. Nevertheless, in January of 1948 Symington informed Boeing that the existing proposal was not suitable, but that no final decision would be made until other possibilities (such as the Northrop YB-49 flying wing) had been explored.
During this period of uncertainty, Boeing engineers had been hard at work in attempting to improve the performance of their design. The result was the Model 464-35, which first appeared in January 1948. It had the same four Wright XT35 turboprops, but the engines now drove a set of coaxial propellers. The wingspan was reduced to 185 feet, wing area to 2600 square feet, and length to 131 feet 4 inches. Considerable attention had been paid to weight reduction, and gross weight was now down to 280,000 pounds. Maximum speed was estimated at 500 mph at 41,000 feet. Maximum range was 11,635 miles.
The performance of the Model 464-35 now appeared to be closer to what the Air Force wanted. In April 1948, Boeing presented a complete Phase II proposal for the design, development and testing of two XB-52s based on the Model 464-35. Although the Model 464-35 was still not all the Air Force wanted, the blockade of Berlin by Soviet forces which began in late June gave a new sense of urgency, and the Air Force endorsed Boeing's Phase II proposal in July.
The B-52 project was now well on its way, and work began on a mockup. However, things were to change yet again, this time even more drastically. In May of 1948, the USAF asked Boeing to explore the possibility of switching to jet engines for the B-52. The Air Force had always been interested in jet power for long-range bombers, but up to now had always ruled them out on the basis of their high fuel consumption. In response to the Air Force request, in late July of 1948, Boeing came up with the Model 464-40. The Model 464-40 was broadly similar to the Model 464-35, but was powered by eight Westinghouse XJ40-13-12 turbojets in underwing podded pairs. Gross weight was 280,000 pounds, and dimensions were wingspan 185 feet and length 130 feet 9 inches. The performance was nominally better than that of the Model 464-35, especially at high altitude--maximum speed was now 507 mph at 47,000 feet.
The Boeing engineers took the Model 464-40 study to the Air Force Project Officer, and he was favorably impressed, especially since he had already been thinking along similar lines. Nevertheless, the government was still concerned about the high fuel consumption rate of the jet engines of the day, and directed that Boeing still use the turboprop-powered Model 464-35 as the basis of its two XB-52s. Although he agreed that turbojet propulsion was definitely the wave of the future, General Howard A. Craig, Deputy Chief of Staff for Material, was not very keen on a jet-powered B-52, since he felt that the jet engine had still not progressed sufficiently far to permit the skipping of the intermediate turboprop stage. However, Boeing was encouraged to continue with turbojet studies even though no commitment to jet propulsion could be expected at present.
Within only a couple of months, everything was to change. On October 21, 1948, a group of Boeing engineers arrived at Wright Field to confer with Air Force officials about the future of the turboprop-powered B-52. The Boeing team had arrived with reams of drawings and figures in preparation for discussions on the progress of their design. They were shocked when Col. Henry Warden of the Wright Air Development Center told them that the turboprop design should be scrubbed and that the turbojet was definitely the way to go. Warden had been pushing Pratt & Whitney to develop the JT3 (J57), a pure jet adaptation of the 10,000 hp T45 turboprop, as a powerplant for the B-52.
Pratt & Whitney had not been a pioneer in jet engine development, the US government having chosen not do divert this manufacturer from its primary task of making its fine series of air-cooled piston engines. P & W's first successful effort in the field of turbine propulsion had been the PT2, which had evolved as the successful T34 turboprop. In 1947, a contract had been given to Pratt & Whitney for the development of a 10,000 hp PT4 (T45) turboprop as a possible powerplant for the B-52 in case the Wright T35 engine did not work out. The PT4 had a dual axial flow compressor of 13 stages, and could easily be converted to a pure turbojet should the need arise.
After giving the idea consideration throughout the afternoon and evening of October 21, the Boeing team called Col. Warden the next morning and told him that they would have a fresh proposal ready by the next Monday. The team went back to the Van Cleeve Hotel in Dayton and worked around the clock all weekend long. Their colleagues back in Seattle were told to stand by to provide data by phone if needed. The Model 464-49 was the result. It featured eight J57 engines in the podded arrangement first proposed for the 464-40. The wingspan remained at 185 feet, but the angle of sweep was increased a further 15 degrees to 35 degrees and the wing area was increased 1400 square feet to 4000 square feet, larger than any previous B-52 submission. Estimated maximum speed was 565 mph at 46,500 feet, and combat radius with a 10,000 pound bomb load was estimated at 3550 miles. Gross weight was estimated at 330,000 pounds. It was felt that the use of jet engines would eliminate the need to tackle the unsolved problems with propeller aerodynamics and control, and a jet-powered B-52 would probably be available almost as quickly as the turboprop variant then under development.
An engineer converted this new design into model form by using balsa wood purchased from a local hobby shop. On Monday morning, the Boeing team delivered their new proposal to the Air Force. Colonel Warden was immediately convinced, and decided that the B-52 would henceforth proceed as a jet-powered aircraft. Boeing immediately halted all work on the Model 464-35 mockup, which was then almost ready. At the same time, Pratt & Whitney was instructed to proceed with the J57 engine.
After a final evaluation in January 1949, the Board of Senior Officers gave the new idea their approval, and decided to continue work on the Boeing proposal as a jet-powered aircraft. Boeing was informed on January 26 that the work on the jet-powered B-52 would proceed under the original contract.
Although the jet-powered B-52 showed considerable promise, the severe budgetary squeeze enforced by the Truman administration on the Defense Department in late 1948 endangered the whole B-52 program. There was also some internal Air Force resistance to the project at several levels, since the decision to proceed with a jet-powered B-52 had leapfrogged over powerplant, armament, and propeller divisions at Wright Field.
The swept-wing turbojet-powered XB-52 mockup was inspected on April 26-29, 1949. The Air Force still had some reservations about the range, since the J57 engine at its current stage of development promised a combat radius of only 2700 nautical miles. General Orville R. Cook, the AMC Director of Procurement and Industrial Planning, was very unhappy about the low range and favored a review of the entire program and perhaps the scheduling of another competition. However, General LeMay, now the commander of the Strategic Air Command, was now thoroughly convinced and strongly backed the B-52, and suggested that the answer to the range problem lay in engine development and that it was unnecessary to accept inferior performance in either speed or range.
In November 1949, convinced that the inadequate range of the Model 464-49 could seriously jeopardize the future of the entire project, Boeing undertook an effort to improve the range. As an answer, Boeing offered a heaver version known as the Model 464-67. The wing remained the same, but the length of the fuselage was increased to 152 feet 8 inches, offering more space for fuel. Gross weight was estimated at 390,000 pounds. Combat radius was estimated at 3500 miles.
The Model 464-67 was looked upon favorably by SAC personnel, including General LeMay. On January 26, 1950, a conference was held at USAF Headquarters to consider once again the future of the B-52. Alternatives were considered once again, including new proposals from Douglas and Republic, Fairchild Aircraft Corporation's idea for a rail-launched flying wing, the swept-wing Convair YB-60, a Rand turboprop aircraft, two new designs based on the B-47, plus several missile aircraft. Although the meeting adjourned without reaching any firm decision, General LeMay still backed the B-52 as providing the best solution for SAC's strategic mission.
In February 1950 the Air Staff requested performance and cost data for all the strategic vehicles so far proposed. In the same month, however, General LeMay asked the Board of Senior Officers to accept the Boeing 464-67 in lieu of the Model 464-49. This choice was approved by the Board on March 24, 1950, but there was still no definitive commitment to production.
It was not until early 1951 that the decision was finally taken to commit the B-52 to production. By this time, the Korean War was in full fury, and the relations between the USA and the USSR were at a new low. General LeMay forcefully argued for the modernization of the strategic bombing force with the B-52. On January 9, 1951, USAF Chief of Staff General Hoyt S. Vandenberg approved a proposal that the B-52 be acquired as a replacement for the B-36. Letter Contract AF33(038)-21096, signed on February 14, 1951, was the first contract authorizing production. It called for an initial batch of 13 B-52As (with serials 52-001/013), with first delivery slated for April of 1953.
Still more controversy broke out among the USAF hierarchy as to whether the B-52 would be better employed as a bomber or a reconnaissance aircraft. SAC wanted a dual-role aircraft which could accommodate a pod-mounted set of reconnaissance sensors that were easily removable so that the aircraft could quickly be reconfigured as a straightforward bomber. USAF Headquarters wanted the B-52 to concentrate on the reconnaissance role with the exclusion of everything else. In October of 1951, the Air Staff issued an order that all aircraft would be RB-52 reconnaissance aircraft. This directive was actually misleading, since it was agreed that the aircraft would retain the ability to be converted for bombardment operations.
Early in 1951, General LeMay told Boeing that he thought that the tandem seating arrangement featured by the XB-52 mockup was poor. General LeMay believed that side-by-side seating of pilot and copilot was superior, since it allowed more room for flight instrumentation and permitted the co-pilot to be a better assistant to the pilot. In August 1951, it was decided that the Air Force would adopt the side-by-side arrangement, but that some of the early production B-52s would still retain the tandem seating arrangement. This was later amended to stipulate that only the two prototypes would retain the tandem seating arrangement, with all production machines having side-by side seating for pilot and co-pilot.
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The XB-52 |
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The Boeing XB-52 was conceived in early 1946 in response to an Army Air Forces request for a large bomber capable of carrying a 10,000 lb. bomb load 5,000 miles at 300+ mph (450+ mph top speed). The original Boeing design was powered by six Wright turboprop engines because the jet engine consumed too much fuel to meet the range requirement. Approval for a mockup design was granted by the US Air Force on 30 September 1947, just 12 days after becoming a separate service. However, about 13 months later the turboprop design was dropped in favor of one with jet engines. About six months later, in March 1949, the design was modified again with a lengthened fuselage required, partly, to accommodate additional fuel cells and increase the range.
The first of two prototype aircraft was ready in late 1951. Ground testing continued until a hydraulic system failure caused extensive damage to the wing trailing edges. The aircraft was rolled back into to the Boeing plant for repair. In the meantime, the second prototype was completed and made its first flight on 15 April 1952.
The XB-52 was repaired and flew for the first time on 2 October 1952. The prototype Stratofortress had a crew of five with the pilot and copilot seated in tandem under a B-47 style canopy. This canopy was only used on the two prototype aircraft (XB-52 & YB-52), all production aircraft had the familiar side-by-side cockpit. With eight jet engines mounted in pairs on a wing with a 35° sweep, the XB-52 had a maximum speed greater than 600 mph. The aircraft was used as a test aircraft for its entire service life, primarily at Wright-Patterson AFB once the initial flight tests were completed. The XB-52 was eventually scrapped in the mid-1960s.
TYPE
XB-52Number Built/Converted
1Remarks
PrototypeNotes:
Serial number: 49-230
Boeing Model 464-67
First flight: 2 October 1952
SPECIFICATIONS
Span: 185 ft. 0 in.
Length: 152 ft. 8 in.
Height: 48 ft. 4 in.
Weight: 390,000 lbs. gross
Armament: Designed for two .50-cal. machine guns in a tail turret plus 25,000 lbs. of bombs
Engines: Eight Pratt & Whitney YJ57-P-3 turbojets of 8,700 lbs. thrust each.
Crew: 5 (Pilot, copilot, navigator, bombardier, tail gunner)
PERFORMANCE
Maximum speed: 610 mph
Cruising speed: 525 mph.
Range: 7,000 miles
Service Ceiling: 50,000 ft.
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The XB-52 Photo gallery |
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XB-52 with Northrop X-4, Convair B-36 in background |
Note the upswept wing flex |
Courtesy Of The Air Force Museum
The YB-52
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The Boeing YB-52 was the second prototype aircraft built and was virtually identical to the XB-52. The YB-52 was initially ordered as the second XB-52, but various changes incorporated into the aircraft on the assembly line warranted a designation change. The aircraft was completed and rolled out for ground testing on 15 March 1952. The first flight of the YB-52 was one month later on 15 April. The XB-52 wings had been damaged during its ground test phase, so the YB-52 was the first B-52-type to fly.
Flight testing of the YB-52 (and XB-52 starting 2 October 1952) showed the aircraft to be very fast for its size. In fact, in early September 1954, the YB-52 made a speed run from the Boeing facilities in Seattle, Washington to Wright-Patterson AFB, OH averaging nearly 625 mph.
General Curtis LeMay, Commnader of the Strategic Air Command, was eager to get the B-52 into production; however, he was strongly opposed to the tandem seating of the pilot and copilot and essentially insisted that the flight deck be redesigned. Boeing designers did just that and changed the entire forward fuselage so the flight crew were seated side-by-side. All production B-52s beginning with the -A model had the new design, only the two prototype aircraft had the B-47 style tandem canopy.
TYPE
YB-52Number Built/Converted
1Remarks
Prototype
Notes:
Serial number: 49-231
Boeing Model 464-67
First flight: 15 April 1952
The YB-52 Photo Gallery
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The XB-52 / YB-52
Once the contracts were let, work on the two XB-52 prototypes proceeded rapidly and they were ready for rollout by late 1951.
The aircraft that emerged had a shoulder-mounted wing with a sweepback angle of 35 degrees. The wingspan was 185 feet, with an area of 4000 square feet. The wing was set at an angle of incidence of six degrees. This was necessary because of the tandem undercarriage layout, which did not permit the aircraft to rotate on takeoff.
According to the standards of the day, the wings were quite thin. On the center line of the of the fuselage, the wing structure had a thickness ratio of 16.2 percent, declining gradually to a thickness ratio of only 8 percent at the tip. Although they were quite thin, the wings carried bladder-type cells for fuel. The thin wings had a considerable amount of flexibility, and could move up or down through a 32 foot arc at the tip without failing. When sitting on the ground with no fuel load, the wings sat high enough so that the outrigger wheels did not actually touch the ground. However, when fully loaded with fuel, the wheels always touched the ground, only rising off the runway after sufficient lifting force has been generated during takeoff. When airborne, the wings generally have an upward curvature.
The eight Pratt & Whitney J57 turbojets were carried two each in four underwing pods. The pods were suspended underneath the wings on pylons. The engines were situated beneath and ahead of the forward edge of the wing. Careful positioning of the engine pods helped to limit the drag rise at high speed and also served to alleviate load factors. The pylons also doubled as wing fences and helped to delay the onset of the stall.
The wings were fitted with four segments of Fowler-type flaps, two on the trailing edge of each wing. Total flap area was 797 square feet. Only two settings were available, fully up or fully down, with the down angle being 35 degrees.
Aerodynamic surfaces on the B-52 wing consisted of a combination of ailerons and spoilers. The ailerons were located on the midwing trailing edges between the inner and outer flap sections, while the seven-segment spoilers were located somewhat further out on the upper wing surface. When operated asymmetrically, the ailerons provided adequate roll control during most normal flight operations, but an additional measure of control could be obtained by using the spoilers during landing or in-flight refueling. When deployed symmetrically, the spoilers could act as airbrakes, making a deceleration chute (such as that used by the B-47) during final approach unnecessary.
The vertical fin was 48 feet 3 inches tall, and incorporated a nearly full-span rudder of rather narrow chord. The entire vertical fin assembly could be folded sideways to allow the aircraft to be wheeled into standard hangars. The horizontal tail surfaces had a span of 52 feet and an area of 900 square feet. The horizontal tail was of the fully-variable type, pivoting through an arc of 13 degrees (9 up, 4 down).
A lot of space in the fuselage was taken up by fuel tanks, with the upper sections from just behind the cockpit to just aft of the rear main undercarriage members being used almost exclusively for fuel. The weapons bay occupied almost the entire section of the lower fuselage between the forward and rear undercarriage members. It was 28 feet long and 6 feet wide, and was enclosed by double-panel doors. Three interconnected and hydraulically-actuated lower panels on each side made up the section of the bomb bay doors that could be opened in flight. While on the ground, the hinged upper panels could be swung back to provide additional clearance for loading and unloading of weapons.
Defensive armament was limited to four 0.50-inch machine guns in a manned tail turret.
The landing gear used double twin-wheeled units mounted side by side underneath the fuselage, one forward and one to the rear. To prevent the wingtips from dragging on the ground during takeoffs or landings, there were small outrigger wheels which retracted into the outer wing. However, the main wheels gave the aircraft enough ground stability so that it could stand by itself without the need for the outrigger wheels. The main landing gear retraction process was fairly complicated, with the wheels swiveling through almost 90 degrees before folding to lie flat within the storage bays. The retraction was asymmetric, with the port units folding forward and the starboard units folding aft. Any one of the four main units could be lowered independently. A unique feature of the landing gear was the ability of the main units to rotate up to 20 degrees left or right of the line of flight. This facilitated crosswind landings and takeoffs by permitting the aircraft to point directly into the wind while the wheels remain aligned with the runway.
Normal crew was five, with pilot and copilot seated in tandem under a bubble-type canopy in the forward nose. The navigator and radar operator sat side-by-side on a lower deck in the forward nose. The tail gunner sat in a separate cockpit in the extreme tail. In an emergency, the pilot and copilot ejected upward and the navigator and radar operator ejected downward. The tail gunner jettisoned the turret by firing four explosive bolts, and he dived after it.
The wing spoilers made the approach chute used by the B-47 unnecessary for the B-52. However, a 44-foot braking parachute was still required to shorten the landing roll. This chute was stowed in a hatch underneath the rear fuselage.
An unusual feature of the B-52 was the use of a pneumatic system as the primary power source in the operation of all auxiliary functions aboard the aircraft. High pressure, high temperature air was bled from the second stage compressor of each jet engine, and carried by ducts to the desired locality in the aircraft where it was transformed into electrical or hydraulic energy by air turbine-driven power packs. There were ten turbine-driven hydraulic pumps which supplied pressure at 3000 pounds per square inch to drive the brakes, steering mechanism, spoilers, bomb bay doors, and the adjustable stabilizer. The pneumatic system also drove air turbine alternators which provided the electrical power for the aircraft.
Two aircraft were completed by Boeing's Seattle factory to serve as" Stratofortress" prototypes. Both had been originally ordered as XB-52s, but the second machine was re-designated as YB-52 in the wake of a 1949 Boeing proposal which recommended installing some operational equipment so that it might serve as a production prototype. This idea apparently fell by the wayside, since there was actually very little difference between the two aircraft when they emerged. The XB-52 and YB-52 were both powered by eight Pratt & Whitney YJ57-P-3 axial-flow turbojets delivering 8700 lb.s.t. each.
On the evening of November 29, 1951, the XB-52 prototype (49-230) was rolled out of the assembly hall and into the flight test hangar. It was covered with a tarpaulin to conceal its shape from prying eyes. It was subjected to a series of ground tests and checkouts. Unfortunately, the XB-52's pneumatic system failed during a full-pressure test and the resulting blow-out severely damaged the wing trailing edge, which required that the aircraft be moved back into the production hall for repair. The company and the Air Force decided to keep this news under wraps and attributed the delay to the installation of further equipment. As a result, the XB-52 did not become airborne until nearly a year later.
Consequently, it was the second prototype, the YB-52, that was actually the first to get airborne. The YB-52 (49-231) rolled out of the assembly hangar on March 15, 1952. The Y prefix indicated service test, but it was essentially identical to the XB-52. It had originally been held back in the factory so that some of the changes found desirable during testing of the XB-52 could be incorporated, but the accident which befell the XB-52 moved it up to primary position.
The first flight of the YB-52 took place on April 15, 1952, with company test pilot A. M. "Tex" Johnston and Lt Col Guy Townsend of the USAF Air Research and Development Command on board. The aircraft stayed in the air for 2 hours and 15 minutes and landed at nearby Larson AFB. Only relatively minor problems were encountered--the failure of one of the main landing gears to retract properly, defects in the liquid oxygen system, and a leaking engine oil valve. The Air Force was so paranoid about security that take-off photographs released to the press had the landing gear units censored out.
By the beginning of October 1952, the YB-52 had logged 50 hours in the air and had begun Phase 1 flight trials.
Almost a year later than originally planned, the XB-52 took off on its maiden flight on October 2, 1952. It stayed up in the air for more than two hours.
Phase II tests were accomplished between November 3, 1952 and March 15, 1953. They turned up some problems with engine reliability, the J57 engines being prone to surge when normal throttle movements were undertaken at high altitude with low engine inlet temperatures. There was a tendency to pitch up and roll to starboard when approaching the stall. The braking system was unable to bring the Stratofortress to a halt within the required distance.
The two prototypes continued an extensive series of flight tests in support of the Stratofortress program. Both the XB-52 and the YB-52 ended their days at the Wright Patterson AFB in Ohio. In 1957, the XB-52 was sent to the Wright Air Development Center at Wright Patterson AFB, Ohio. It later flew as a six-engine aircraft, with four J57s inboard and two J75s outboard. After logging 783 flying hours, the YB-52 was donated to the USAF Museum at Wright Patterson AFB in Ohio on January 27, 1958. Unfortunately, both aircraft were scrapped in the mid-1960s. They were victims of Lady Bird Johnson's national beautification program, which sought to remove eyesores such as surplus military hardware from the landscape.
Specification of Boeing YB-52 Stratofortress
Engines: Eight Pratt & Whitney YJ57-P-3 turbojets, each rated at 8700 lb.s.t. Performance: Maximum speed 611 mph at 20,000 feet, 594 mph at 35,000 feet. Cruising speed 519 mph. Stalling speed 146 mph. Initial climb rate 4550 feet per minute. Combat radius 3545 miles with 10,000 pound bombload. Ferry range 7015 miles. Dimensions: Length 152 feet 8 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 155,200 pounds empty 405,000 pounds gross. Armanent: Not fitted with any defensive armament. Maximum offensive payload 43,000 pounds.
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The NB-52A |
Click on Picture to enlarge
After completion of acceptance and standard B-52 service tests, the last B-52A (S/N 52-003) was modified as a carrier (mother ship) for the North American X-15. A mounting pylon for the X-15 was installed between the fuselage and the right inboard engine nacelle. The pylon had mount points to attach the X-15 and service lines which kept the fuel cells (liquid oxygen and hydrogen peroxide) topped off while climbing to altitude.
When preparing for a test flight, the X-15 was mated to the NB-52A on the ground. The X-15 pilot was sealed into the cockpit on the ground as well. The NB-52A would typically carry the X-15 to about 45,000 ft. and release the aircraft at about 500 mph. The X-15 would then fire its engines for about 2 minutes of powered flight followed by 10 minutes of unpowered flight while returning to the landing zone at Edwards AFB, California.
One RB-52B (S/N 52-008) was similarly modified and designated NB-52B. This aircraft was used for the X-15 program, but also was used as a carrier during the lifting body research program.
TYPE
NB-52ANumber Built/Converted
1 (cv)Remarks
X-15 Mothership
Notes:
Serial numbers: 52-003
Boeing Model 464-201-0
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The NB-52A Photo Gallery |
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Click on Picture to enlarge |
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| Take off with X-15 #3 (S/N 56-6672) on 17 July 1962 when Major White flew to an altitude of 314,750 ft. The NB-52A was named 'The High and Mighty One" at this time. Note the X-15 mission markings on the fuselage just forward of the wing. The horizontal ones are for unpowered flights and the near vertical marks for powered flights |
With X-15 #1 (S/N 56-6670)
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| With X-15A-2 (S/N 56-6671) The USAF Museum has this X-15 on display |
Just after releasing X-15 #1 for a test flight |
Read About
The B-52A
Click on Picture to enlarge
Thirteen B-52As were ordered in early 1951, but the contract was amended in June 1952 reducing the order to just three aircraft. The other 10 aircraft on contract were built as RB-52B reconnaissance bombers. The -A differed from the prototype XB-52 and YB-52 in a number of ways, but the most obvious was the redesigned forward fuselage. The tandem cockpit arrangement was dropped at the insistence of General Curtis LeMay, Commander of the Strategic Air Command at that time. The pilot and copilot were seated side by side in the new design. The forward fuselage was also lengthened to accommodate additional equipment and one more crew member: the electronic warfare officer (EWO). The EWO was responsible for electronic defense (jamming enemy radar, etc.) of the aircraft. The aircraft defensive armament consisted of only four .50-cal. machine guns in a power tail barbette operated by the tail gunner.
None of the -A models ever saw operational service and were used by Boeing for service testing for years after they were built. The first B-52A was rolled out in March 1954 and made its first flight 5 months later in August. The B-52A was capable of carrying an external tank on the each outboard wing although the tanks were very rarely mounted. The aircraft was also fitted with an in-flight refueling system capable of receiving fuel from tankers fitted with the boom-type system (KC-97s initially).
After completion of service testing, the first B-52A (52-001) continued as a test aircraft and was used to test improvements planned for later B-52 models. The last B-52A (52-003) was modified as a carrier (mothership) for the X-15 program and redesignated NB-52A.
TYPE
B-52ANumber Built/Converted
3Remarks
Service test aircraft
Notes:
Serial numbers: 52-001 to 52-003
Boeing Model 464-201-0
First flight: 5 August 1954
B-52A Photo Gallery
Click on Picture to enlarge
Courtesy Of The Air Force Museun
The B-52A
By Joe Baughe
The first production version of the Stratofortress was the B-52A (Model 464-201-0). Contract AF33(038)-21096, officially signed on February 14, 1951, had originally called for 13 B-52As, but this was amended on June 9, 1952 to cover just three, with the remainder being earmarked for completion as B-52Bs.
The B-52A differed from the X/YB-52 in having a completely redesigned forward fuselage. The original bubble canopy and tandem seating arrangement for pilot and copilot were replaced by a side-by-side arrangement. General Curtis E. LeMay was largely responsible for insisting on this change. The forward fuselage was lengthened by 21 inches so as to accommodate additional equipment and an extra crew member. The crew was now six--pilot, copilot, navigator, radar operator, electronic warfare officer, and tail gunner. The pilot and co-pilot sat side-by-side in the upper deck of the forward fuselage, with the electronic warfare officer sitting behind the pilot facing to the rear. The navigator and the radar operator sat side-by side in the lower deck of the forward fuselage. The tail gunner sat all by himself in a station in the extreme tail behind the tall rudder.
Entry to the cockpit was via a door located on the fuselage underside offset to starboard and hinged at the rear. The gunner had his own entry door in the starboard aft fuselage side below the horizontal tail surface. The tail gunner was normally isolated from the rest of the crew, but he could move forward via a crawlway to the weapons bay, and from there he had access to the main crew compartment via a small access door that was cut into the aft cabin pressure bulkhead. However, cabin depressurization was necessary before he could do this.
In an emergency, the pilot, copilot, and electronic warfare officer ejected upwards, and the navigator and radar operator ejected downwards. The tail gunner did not have an ejector seat--he got out by jettisoning the turret and diving after it. When extra crew members were on board, they would evacuate the aircraft by jumping through the holes in the fuselage bottom left by the departure of the navigator's and radar operator's ejector seats.
The engines of the B-52A were more powerful than the largely- experimental engines of the prototypes. The powerplants were a set of eight Pratt & Whitney J57-P-1W turbojets, offering a dry thrust of 10,000 pounds. They were equipped for water injection, raising the thrust to 11,000 lb.s.t for short periods. This water was provided by a 360-gallon tank carried in the rear fuselage.
A 1000-gallon auxiliary underwing fuel tank was provided outboard of the outrigger wheels. These tanks had also been fitted to both prototypes. However, it appears that the B-52As flew without these tanks more often than with them.
The B-52A was fitted with an in-flight refueling receptacle for midair refueling via the flying-boom technique. This receptacle was mounted on the upper fuselage just behind the cockpit. A couple of doors above the receptacle opened to allow the probe from the refuelling aircraft to attach itself to the B-52 for the transfer of fuel.
The B-52A was the first to be fitted with defensive armament--a battery of four 0.50-inch M3 machine guns in the extreme tail. Each gun had 600 rounds of ammunition. The tail gunner, seated in the extreme rear of the plane underneath a transparent canopy, was provided with an A-3A fire control system which employed search and tracking radar antenna and which could automatically aim and fire the guns. However, the gunner also had a periscopic optical gun sight for manual operation of the guns.
The first B-52A (52-001) was rolled out at Seattle on March 18, 1954 with appropriate fanfare. Several thousand people were there for the ceremony, and USAF Chief of Staff General Nathan F. Twining addressed the crowd. It made its first flight on August 5, 1954.
Although the 3 B-52As were referred to as true production machines, they lacked certain vital operational equipment, and were not considered as being combat-ready. In particular, no bombing/navigation system was fitted, and much of the vital electronic equipment was not actually installed. Consequently, it is probably more accurate to describe the B-52As as pre-production service test and evaluation machines rather than as true production aircraft.
None of the B-52As ever entered operational service with the USAF. All three of them were used by Boeing for various test flight duties for the next ten years or so. In the mid- to late-1950s, 52-001 was used for tests of B-52G features such as the short fin. It reportedly bore the designation "XB-52G" during these tests. In the early 1960s, 52-0001 was flown to Chanute AFB in Illinois, where it was permanently grounded and used as a teaching aid. 52-002 was scrapped at Tinker AFB in Oklahoma in 1961. In November of 1958, 52-003 was modified to NB-52A standard and used as a "mother ship" for the X-15 rocket-powered research aircraft. The X-15 was carried and launched from a special cradle mounted on a pylon installed underneath the inner starboard wing. In October of 1969, 52-003 was retired to storage at Davis Monthan AFB in Arizona. It was later passed along to the Pima County Air Museum at Tucson, Arizona.
Serials of B-52A:
52-001/003 Boeing B-52A-1-BO Stratofortress c/n 16491/16493Specification of Boeing B-52A Stratofortress:
Engines: Eight Pratt & Whitney J57-P-1W turbojets, each rated at 10,000 lb.s.t. dry and 11,000 lb.s.t with water injection. Performance: Combat radius 3590 miles. Dimensions: Length 156 feet 6.9 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 420,000 pounds maximum takeoff. Armament: Four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 43,000 pounds.
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
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The B-52B |
Click on Picture to enlarge
The -B model was the first aircraft in the B-52 series to actually serve with operational bomb wings in the Strategic Air Command. Because of high level disagreements over the primary role of the B-52--long range bomber or strategic reconnaissance--the production contracts were changed many times. Initially 13 B-52As were ordered as the initial production block; however, only three -A models were actually built (S/N 52-001 to 52-003). The other ten aircraft on contract were to be built as -B models (52-004 to 52-013). Seven additional aircraft were added to the contract (S/N 52-8710 to 52-8716) bringing the total to 17 B-52Bs on order. This production contract was changed again and all aircraft were to be built as reconnaissance variants (RB-52B). By mid-1954, and many contract changes, the number of B-52B was set at 23 while the RB-52B contracts amounted to 27 aircraft.
The first flight of a -B model was on 25 January 1955 and initial delivery to the 93rd Bomb Wing (H) at Castle AFB, CA occurred in the summer of 1955. Although the 93rd BW was considered an operational unit, its primary mission was transition training for new B-52 crews. Eventually, the -B models (RB-52Bs included) were used by the 95th, 99th and 22nd Bomb Wings in addition to the 93rd. The -B models remained in service into the mid-1960s when the aircraft were 'traded in' for more modern B-52s.
TYPE
B-52BNumber Built/Converted
23Remarks
First operational model
Notes:
Serial numbers: 53-373 to 53-376; 53-380 to 53-398
Boeing Model 464-201-3
First flight: 25 January 1955
SPECIFICATIONS and PERFORMANCE Same as above
Armament: Four .50-cal. M-3 machine guns plus 43,000 lbs. of bombs
The B-52B Photo Gallery
Click on Picture to enlarge
Courtesy Of The Air Force Museum
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The RB-52B |
Click on Picture to enlarge
The RB-52B, though also usable as a normal bomber, was designed as a reconnaissance variant of the B-52B.In its reconnaissance role, a large Module/Reconnaissance Capsule was designed and procured which could be loaded into the bomb bay, completely filling the space. This pressurized Module included provisions for two additional crew members, and would equip the RB-52B for photo reconnaissance, electronic intelligence gathering, weather data gathering, or general observations. One of these Capsules was installed on RB-52B S/N 52-8716 for an unsuccessful training mission on 30 November 1956 (see photo and caption below). Although they were retained in Air Force inventory these Capsules were never employed operationally."
Without the reconnaissance pod in the bomb bay, the RB-52B was essentially the same as the standard B-52B and could perform the same bombing missions. A total of 50 -B models were ordered with 27 being built as RB-52 dual role aircraft and the other 23 as single role bombers.
There was disagreement within the USAF general staff over whether the B-52 should be primarily a bomber or a reconnaissance plane. The order for 13 B-52As was split into an order for only 3 -A models and the other 10 for B-52Bs. The contract for the 10 -B models was amended to include 7 more aircraft and later changed to an RB-52B order. The Strategic Air Command and its commander, General Curtis LeMay, wanted the B-52 as a bomber and fought against the reconnaissance variant. Although the reconnaissance version was built in slightly greater numbers than the bomber, the fact that the RB-52B could easily and quickly be converted for bombing missions satisfied SAC when they started taking delivery of the aircraft in June 1955.
The B-52B and RB-52Bs were the first versions in the B-52 series to actually go into operational service. The 93rd Bomb Wing at Castle AFB, California was the first unit to get the -B model and used them initially for transition crew training. Other wings receiving -B models included the 95th, 99th and 22nd. The -B model was retired from operational service in the mid-1960s, but one RB-52B (S/N 52-0008) was modified for use as a carrier aircraft (mothership) for the X-15 and Lifting Body flight research programs. This aircraft is still in use at the NASA Dryden Flight Research Center (Edwards AFB) in California.
TYPE
RB-52BNumber Built/Converted
27Remarks
Reconnaissance bomber version
Notes:
Serial numbers: 52-0004 to 52-0013; 52-8710 to 52-8716; 53-0366 to 53-0372; 53-0377 to 53-0379
Boeing Model 464-201-3
Boeing RB-52B Photo Gallery
Click on Picture to enlarge
Courtesy Of The Air Force Museum
The NB-52B
Click on Picture to enlarge
One RB-52B (S/N 52-008) was converted for use as a carrier aircraft (The Mother-ship) for the North American X-15 and Lifting Body research programs. The aircraft was re-designated NB-52B after conversion and joined the NB-52A (See Above) as the B-52 mother-ship at Edwards AFB.
Basic modifications to the aircraft included the removal of all offensive and defensive armament systems and installation of a carrier pylon between the fuselage and the right inboard engine nacelle. Specialized equipment to support the experimental flight research program was also installed.
The NB-52B is still used as a test aircraft and carrier aircraft for research vehicles at the NASA Dryden Flight Research Center. In addition to supporting the X-15 and Lifting Body programs, the NB-52B was used as a mother-ship for the Spin Research Vehicle, DAST, Pegasus and X-38 programs, it was also used to test drag chutes for the F-111 and space shuttle.
TYPE
NB-52BNumber Built/Converted
1 (cv)Remarks
X-15 & lifting body mothership
Notes:
Serial number: 52-008
Go To
Boeing NB-52B Photo Gallery
Click on Picture to enlarge
The RB-52B / B-52B
By Joe Baugher
The B-52B was the first truly operational version of the Stratofortress. The B-52B was outwardly identical to the B-52A, but featured an enhanced reconnaissance capability and was fitted with a bombing/navigation system. A total of 50 were built, with 23 being pure bomber B-52Bs and 27 being dual-capable reconnaissance/bomber RB-52Bs. All of them were built at Seattle.
Letter Contract AF33(038)-21096 of February 1951 originally specified 13 B-52As but was changed on June 9, 1952 to include only 3 B-52As, with the remainder to be delivered as B-52Bs. Another seven aircraft were added to the contract at this time. As it turned out, all 17 of these aircraft were actually completed as RB-52Bs. Serials were 52-0004/0013 and 52-8710/8716
Further B-52Bs were ordered later. Letter Contract AF33(600)-22119 was initially drawn up in September of 1952 and formally signed on April 15, 1953. The contract called for 43 RB-52Bs. In April 1954, the contract was amended and the number of RB-52Bs was cut to 33, with the remaining ten machines to be completed as B-52Cs. As it turned out, only ten of these aircraft were actually built as RB-52Bs, with the rest being delivered as B-52Bs. Serials were 53-0366/0398.
The RB-52B had been the result of an earlier disagreement among Air Force officers about what the true role of the B-52 should be--a pure bomber or a pure reconnaissance aircraft. Although bearing an R prefix, the RB-52B could be reconfigured in a matter of hours for either a reconnaissance or a bombardment mission. The RB-52Bs carried out its reconnaissance mission via a two-man pressurized capsule installed in the bomb bay which could perform electronic countermeasures or photographic reconnaissance work. Downward-firing ejector seats were provided for the crew in the case of an inflight emergency. Equipment inside the capsule could be optimized for different types of intelligence-gathering missions and included long-focal length and panoramic camers, plus photoflash bombs, mapping radars, receivers, pulse analyzers and recorders. For search operations, the pod had one AN/APR-14 low-frequency radar receiver and two AN/APR-9 high-frequency radar receivers. Each station had two AN/APA-11A pulse analyzers. The station also had three AN/ARR-88 panoramic receivers and all electronic data was recorded on an AN/ANQ-1A wire recorder. Photographic equipment could include 4 K-38 cameras at the multi-camera station plus one T-11 or K-36 at the vertical camera station. The pod could also carry three T-11 cartographic cameras. The reconfiguring of the aircraft was a fairly straightforward process and the pod could usually be installed in about four hours.
At the beginning, the engines of the B-52B/RB-52B were J57-P-1W, -1WA or -1WB turbojets with water injection, the same engines which had powered the B-52A. These were rated at 10,000 lb.s.t. dry and 11,000 lb.s.t. with water injection. About half of the B-52B/RB-52Bs were delivered with these engines. In the meantime, there were attempts to correct problems which had been encountered with the water injection system. These efforts were expected to lead to the J57-P-9W engine with titanium compressor blades. Unfortunately, problems with the manufacture of the blades forced a return to steel blades in the J57-P-29W and J57-P-29WA engines which were installed in the bulk of the remaining B-52B/RB-52Bs. The -29W was rated at 10,500 lb.s.t dry and 11,000 lb.s.t wet. The -29WA had twice the water flow rate as the -29W, and had a 12,100 lb.s.t wet rating. The problems with the titanium blades were finally overcome in the summer of 1956, which led to the J57-P-19W version, which was installed in the final five aircraft delivered.
The first B-52B took off on its maiden flight in December of 1954. The first B-52B (52-8711) was delivered to the 93rd Bombardment Wing at Castle AFB in California on June 29, 1955. Over the next few months, the 93rd BW traded in its B-47s for B-52Bs, and changed its name to the 93rd Bombardment Wing (Heavy). The 93rd BW was declared combat ready on March 12, 1956, but its primary mission was the training of future B-52 crews. The initial teething troubles with the B-52 were not nearly as severe as those encountered with the early B-47. However there were difficulties with the fuel system, imperfect water injection pumps, faulty alternators, and especially with deficient bombing and fire control systems.
The B-52B had originally been intended to carry the MA-2 bombing/navigation system, which combined an optical bombsight, a radar presentation of target, and an automatic computer, together with radar modifications designed for use in a high-speed aircraft. However, the development of this package had been delayed. Consequently, SAC had decided to equip some of the early production B-52 aircraft with the Sperry K-3A system that was used by the B-36. Unfortunately, at heights of 45,000 feet where the B-52B typically operated, the K-3A system was found to be almost totally ineffective--poor resolution qualities and a loss of definition made it almost impossible to identify targets with any degree of certainty. The Philco Corporation developed a temporary fix in which power output was increased by about 50 percent, but this was not really much of a solution and things really did not improve very much until the IBM MA-6A system was finally available during the latter stages of the B-model production run.
There were also problems experienced with the fire control system for the tail-mounted defensive armament. Nine of the first ten RB-52Bs (52-004/008 and 52-010/013 used a A-3A fire control system which operated a quartet of 0.50-inch machine guns. However, one early RB-52B (52-0009) was fitted with the alternative MD-5 fire control system which incorporated a pair of M24A-1 20-mm cannon. This system was adopted as standard equipment on the remaining 17 RB-52Bs and 16 B-52Bs (52-8710/8716 and 53-0366/0391). However, the new system proved to offer no real improvement, and the last seven B-52Bs reverted to the original system of four machine guns with a supposedly improved A-3A fire control system. However, in reality, many of the problems remained.
The original electrical system of the B-52 consisted of four air turbine-driven 60 KVA alternators furnishing 200/115 volt three-phase 400 cycle alternating current. The first fatal B-52 crash in February 1956 was blamed on a faulty alternator. This caused the immediate grounding of 20 B-52Bs and the halting in delivery of further B-52Bs while the problem was addressed. In mid-May, deliveries were resumed, but the alternator problem later reappeared.
In July 1956, there was another temporary grounding of the B-52B fleet, this time because of fuel system and hydraulic pack deficiencies. Although this grounding did not last long, the 93rd BW's training program was adversely affected, and by mid-year there were still no combat-ready B-52 crews.
The last B-52B was delivered in August of 1956.
A program known as Sunflower brought 7 early B-52Bs up to B-52C standards. B-52Bs also went through many other modifications in subsequent programs such as Harvest Moon, Blue Band, and Quickclip, which were initially intended for the benefit of subsequent B-52 models.
Serials of B-52B/RB-52B
52-004/006 Boeing RB-52B-5-BO Stratofortress c/n 16494/16496 52-007/013 Boeing RB-52B-10-BO Stratofortress c/n 16497/16503 52-8710/8715 Boeing RB-52B-15-BO Stratofortress c/n 16838/16843 52-8716 Boeing RB-52B-20-BO Stratofortress c/n 16844 53-366/372 Boeing RB-52B-25-BO Stratofortress c/n 16845/16851 53-373/376 Boeing B-52B-25-BO Stratofortress c/n 16852/16855 53-377/379 Boeing RB-52B-30-BO Stratofortress c/n 16856/16858 53-380/387 Boeing B-52B-30-BO Stratofortress c/n 16859/16866 53-388/398 Boeing B-52B-35-BO Stratofortress c/n 16867/16877Specification of Boeing B-52B Stratofortress:
Engines: Eight Pratt & Whitney J57-P-1W, -1WA, or -1WB turbojets, each rated at 11,400 lb.s.t with water injection. Later, Eight Pratt & Whitney J57-P-29W or -29WA turbojets, each rated at 10,500 lb.s.t dry and 12,100 lb.s.t. with water injection. Last five were fitted with eight Pratt & Whitney J57-P-19W turbojets, each rated at 10,500 lb.s.t dry and 12,100 lb.s.t. with water injection. Performance: Maximum speed 630 mph at 19,800 feet, 598 mph at 35,000 feet, 571 mph at 45,750 feet. Cruising speed 523 mph Service ceiling at combat weight 47,300 feet. Initial climb rate 4750 feet per minute. Combat radius 3590 miles with 10,000 pound bombload. Ferry range 7343 miles. Takeoff ground run 8200 feet. Takeoff over a 50-foot obstacle 10,500 feet. Dimensions: Length 156 feet 6.9 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 164,081 pounds empty, 272,000 pounds combat, 420,000 pounds maximum takeoff. Armament: Two 20-mm M24A1 cannon with 400 rpg or four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 43,000 pounds.
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
Service Of The RB-52B / B-52B By Joe Baugher
The first B-52B (52-8711) was delivered to the 93rd Bombardment Wing at Castle AFB in California on June 29, 1955. Over the next few months, the 93rd BW traded in its B-47s for B-52Bs, and changed its name to the 93rd Bombardment Wing (Heavy). The 93rd BW was declared combat ready on March 12, 1956, but its primary mission was actually the training of future B-52 crews. For this purpose, it set up the 4017th Combat Crew Training Squadron which was supposed to handle all B-52 crew training for the next few years. When the mission of B-52 training became too great a task for just one squadron, the Wing's other three squadrons took over the flight training role and the 4017th assumed responsibility for ground instruction in 1956.
The last B-52B was delivered in August of 1956.
On May 21, 1956, B-52B 52-0013 flying with the Air Research and Development Command dropped a hydrogen bomb over the Bikini Atoll. The weapon was a Mk.15 which weighed 7600 pounds and was 10 feet long. The yield of the test was 3.75 megatons. It was the first time that a B-52 had been used as a carrier and drop plane for the hydrogen bomb.
On November 24 and 25, 1956, in a spectacular operation known as Quick Kick, four B-52Bs of the 93rd BW joined four B-52Cs of the 42nd BW for a nonstop flight around the perimeter of North America. Four in-flight refueling by KC-97 tankers were required for the 13,500 nautical mile journey.
In January 1957, three aircraft of the 93rd Bombardment Wing commanded by Major General Archie Olds, flew nonstop around the world with the help of several KC-97 in-flight refueling. Five aircraft, including two spares, took off on January 16 from Castle AFB. They flew via Newfoundland, Casablanca, Dhahran, Ceylon, the Malay Peninsula, Manila, and Guam. Bad weather forced them to land at March AFB. One spare had to divert to Goose Bay when the in-flight refueling receptacle iced over. The second made a planned landing in England. The 24,235 mile flight was completed in 45 hours 19 minutes. The commander of the lead aircraft, Lt Col James H. Morris had been copilot of the "Lucky Lady II" which had made the first round-the-world flight in 1949.
Some B-52Bs remained with the 93rd BW until well into the 1960s, although some of the B-52Bs were redistributed to the 95th BW at Biggs AFB in Texas and the 22nd BW at March AFB in California.
The following units used the B-52B:
22nd Bombardment Wing (Heavy), March AFB, California
2nd Bombardment Squadron 1963-1966 - Converted to B-52D 1966
93rd Bombardment Wing (Heavy), Castle AFB, California
328th Bombardment Squadron, 1955-1965
329th Bombardment Squadron, 1955-1965
330th Bombardment Squadron, 1955-1963 - Inactivated 9/15/63
4017th CCTS, 1955-1956
95th Bombardment Wing (Heavy), Biggs AFB, Texas
334th Bombardment Squadron 1959-1966. Inactivated 6/25/66.
99th Bombardment Wing (Heavy), Westover AFB, Massachusetts
346th Bombardment Squadron, 1958-59
347th Bombardment Squadron, 1958-59
348th Bombardment Squadron, 1958-59
In June of 1959, B-52B serial number 52-0008 was transferred to NASA, where it served alongside the NB-52A as a mother ship for the X-15 and with the Lifting Body project. It was re-designated NB-52B and assigned the number "008". It was credited with 140 of the 199 X-15 flights. It is still active with NASA's Dryden Flight Research Facility at Edwards AFB.
Most of the B-52Bs were retired in 1965-66, with 52-8714 being the first Stratofortress to be retired by a SAC wing when it was transferred to Chanute AFB in Illinois on March 8, 1965, where it was used as a non-flying instructional airframe. Most of the B-52Bs went to storage at Davis-Monthan AFB in Arizona in 1965/66, but a few were delivered to museums. 52-8711, the first B-52 to be received by SAC, was donated to the Aerospace Museum at Offutt AFB in Nebraska.
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
The B-52C
Click on Picture to enlarge
The B-52C was an improved version of the -B model with most of the modifications done to internal aircraft systems. One of the few and most obvious external differences was the addition of 3,000 gallon tip tanks in place of the 1,000 gallon tanks on the -B model. The aircraft was also left in bare metal finish except for the underside which was painted gloss white. The paint was designed to reflect heat and radiation from a nuclear blast.
Thirty five aircraft were ordered and the first flight occurred on 9 March 1956. Initial deliveries of the -C model to the USAF (42nd Bomb Wing) took place in June 1956. The B-52C was capable of carrying the multi-mission reconnaissance-observation pod designed for the RB-52B, but the aircraft retained its bomber designation (B-52C rather than RB-52C).
The first B-52C built (S/N 53-399) was retained for service and modification testing and assigned to the Aeronautical Systems Division (ASD) at Wright-Patterson AFB, Ohio. The aircraft was redesignated as JB-52C or NB-52C depending on the specific project.
Various improvement projects done during the -C models operational lifetime essentially brought it up to -D model standards. These improved B-52Cs served in Southeast Asia along with the B-52D. The B-52C remained in service until 1971 when the last aircraft was retired.
TYPE
B-52CNumber Built/Converted
35Remarks
Improved -B model
Notes:
Serial numbers: 53-399 to 53-408; 54-2664 to 54-2688
Boeing Model 464-201-6
First flight: 9 March 1956
B-52C Photo Gallery
Click on Picture to enlarge
The B-52C
By Joe Baugher
The next Stratofortress version was the B-52C (Model 464-201-6). It was the last Stratofortress version to be built solely at Seattle.
Only 35 B-52Cs were built. Letter Contract F33(600)-22119 of September 1952 had originally covered 43 RB-52Bs, but it was amended in May of 1954 to have the last ten examples delivered as RB-52Cs. At the same time, 25 more RB-52Cs were added to the order. In the event, all the planes were actually delivered as B-52Cs, but with dual bomber and reconnaissance capability. When fitted with the reconnaissance pods, the designation RB-52C was sometimes applied, although this designation was never used officially.
The primary difference between the B-52C and the earlier A and B models was that the B-52C featured much larger auxiliary underwing fuel tanks, with the 1000-gallon units of the B-52A and B being replaced by 3000-gallon tanks. This increased the total fuel capacity to 41,700 US gallons, which significantly extended the aircraft's unrefuelled range.
The powerplants of the B-52C were still the J57-P-19W or J57-P-29WA engines that had been used by the late B-52Bs. The gross weight was now up to 450,000 pounds.
The B-52B had initially been equipped with the Sperry K-3A navigation/bombardment system, which had turned out to be almost useless for high-altitude bombing. A temporary expedient was the IBM MA-6A, which was installed in the later B-52Bs. A vastly improved navigation/bombing system, the AN/ASB-15, initially equipped the B-52C. Later in its career, the B-52C was retrofitted with the AN/ASQ-48 bombing/navigation package at the same time that this equipment was fitted across the entire B-52D fleet.
The defensive armament of the B-52C comprised a battery of four 0.50-inch machine guns, just as it had on most of the B-52Bs. In the B-52B, these guns were directed by an MD-5 fire-control system which had a lot of bugs and had not lived up to expectations. All but one of the B-52Cs used the supposedly improved A-3A fire control system that had been used on the last seven B-52Bs. Unfortunately, the A-3A was itself less than fully reliable, and the last B-52C (54-2688) was fitted with an improved MD-9 fire control system, a system which was fitted to subsequent B-52 models.
The cause of a B-52B crash in February of 1956 had been traced to a faulty turbine-driven alternator. A new Thompson Products Company alternator was installed on the B-52C, which was much better but was still troublesome. Problems were traced to defects in the alternator drive's lubricating system. Another B-52 problem had to do with the trunnion fittings of the main landing gear, and defective fittings were found in nearly all B-52Cs.
The first B-52C flew on March 9, 1956. The last 5 B-52Cs reached the Air Force in December of 1956. All of them went to the 42nd Bombardment Wing based at Loring AFB in Maine and to the 99th Bombardment Wing at Westover AFB in Massachusetts.
Another innovation first introduced on the B-52C was a new paint job. The undersides of the fuselage of the B-52C fuselage and wings were painted at the factory in gloss white anti-flash paint. This paint was intended to reflect away some of the thermal radiation from a nuclear detonation, making the B-52C less vulnerable to damage caused by the release of its own bomb. National markings, USAF lettering, and other markings were not applied over the reflective paint. This system came into vogue in 1956, and was generally applied to most of those aircraft that were capable of delivering nuclear weapons, and some of the earlier B-52Bs were painted in this fashion during subsequent modification programs.
A special project known as Harvest Moon increased the B-52C's combat potential to that of the B-52D. The B-52C was also involved in other large programs that concerned themselves with the overall improvement of the entire B-52 fleet.
Specification of Boeing B-52C Stratofortress:
Engines: Eight Pratt & Whitney J57-P-29WA or -19W turbojets, each rated at 12,100 lb.s.t with water injection. Performance: Maximum speed 636 mph at 20,200 feet, 570 mph at 45,000 feet. Cruising speed 521 mph. Stalling speed 169 mph. Initial climb rate 5125 feet per minute. Service ceiling at combat weight 45,800 feet. Combat radius 3475 miles with 10,000 pound bombload. Ferry range 7856 miles. Takeoff ground run 8000 feet. Takeoff over 50 foot obstacle in 10,300 feet. Dimensions: Length 156 feet 6.9 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 164,486 pounds empty, 293,100 pounds combat, 450,000 pounds maximum takeoff. Armament: Four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 43,000 pounds.
Serial Numbers of B-52C:
53-0399/0408 Boeing B-52C-40-BO Stratofortress c/n 16878/16887 54-2664/2675 Boeing B-52C-45-BO Stratofortress c/n 17159/17170 54-2676/2688 Boeing B-52C-50-BO Stratofortress c/n 17171/17183Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
|
Service Of The B-52C |
By Joe Baugher
The first B-52C flew on March 9, 1956. The last 5 B-52Cs reached the Air Force in December of 1956. All of them went to the 42nd Bombardment Wing based at Loring AFB in Maine and to the 99th Bombardment Wing at Westover AFB in Massachusetts.
The following organizations flew the B-52C:
42nd Bombardment Wing (Heavy), Loring AFB, Maine
Disposed of its B-52Cs in 1957 when first B-52Ds
arrived. B-52Cs then dispersed to other wings as trainers.
69th Bombardment Squadron - 1956-1957
70th Bombardment Squadron - 1956-1957
75th Bombardment Squadron - 1956-1957
99th Bombardment Wing (Heavy), Westover AFB,
Massachusetts
346th Bombardment Squadron - 1956-1966
347th Bombardment Squadron - 1956-1961
348th Bombardment Squadron - 1956-1966
After several years of service with two squadrons of the 99th Bombardment Wing, in the latter half of the 1960s their B-52Cs were redistributed among a number of different B-52D units and operated primarily as crew trainers until 1971. Units known to have operated the B-52C in this fashion included the 7th BW, 22nd BW, 28th BW, 70th BW, 91st BW, 92nd SAW, 96th SAW, 99th BW, 306th BW, 454th BW, 461st BW, and 509th BW.
In December 1965, a few months after the first B-52Bs had started to leave the operational inventory, Defense Secretary Robert S. MacNamara announced another phase out program that would further reduce SAC's bomber force. Included in the program was a plan to retire all B-58 Hustlers. In addition, it was decided to put the B-52C in storage, along with several subsequent B-52 models. The phased-out bombers were to be replaced by the General Dynamics FB-111, a derivative of the controversial F-111 swing-wing fighter-bomber. By this time, the B-52Cs were operating primarily as trainers rather than as operational strategic bombers. The phaseout of the B-52Cs actually took several more years, and most of them remained flying until they were finally consigned to storage at Davis-Monthan AFB in 1971. A few B-52Cs remained flying for a few years longer--the last aircraft to be withdrawn ended its flying career with the Air Force Flight Test Center at Edwards AFB in July of 1975.
Sources:
American Combat Planes, Third Enlarged Edition, Ray
Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack,
Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval
Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon
Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne,
Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress,
Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
E-mail from Steve Tobey. The B-52C also served with the 7th BW during the late 1960s.
The B-52D
Click on Picture to enlarge
The B-52D was an improved version of the B-52C with mostly minor changes incorporated into the aircraft systems. The ability to carry to bomb-bay mounted reconnaissance and observation pod was eliminated and the -D model was used only as a bomber.
The B-52D was used extensively in Southeast Asia beginning in the mid-1960s. Operating from Andersen AFB, Guam and later U-Tapao Royal Thai Air Base, the B-52 was a major component of many operations including Arc Light, Iron Hand, Rolling Thunder, Linebacker and Linebacker II.
The B-52D remained in service until 1983 when the last aircraft of the 7th Bomb Wing were retired.
The USAF Museum has a B-52D on display in the Modern Flight Hangar which saw extensive service in Vietnam. The aircraft was hit by a an enemy missile and severely damaged during a mission on 9 April 1972.
TYPE
B-52DNumber Built/Converted
170Remarks
Improved -C model
Notes:
Serial numbers: 55-0049 to 55-0117; 55-0673 to 55-0680; 56-0580 to 56-0630; 56-0657 to 56-0698
Boeing Model 464-201-7
First flight: 14 May 1956
B-52C Photo Gallery
Click on Picture to enlarge
The B-52D
By Joe Baugher
The first large-scale production version of the Stratofortress was the B-52D (Model 464-201-7), of which 170 were built between June 1956 and November 1957. The B-52D was externally indistinguishable from the B-52C which preceded it. The only significant internal difference was the adoption of the MD-9 fire control system as fitted to the final B-52C. The powerplants were the J57-P-19W or -29W. In contrast to the B-52C, which was readily convertible to the reconnaissance configuration, the B-52D was built exclusively for the long-range bombing role.
The B-52D was the first Stratofortress to be built at two different locations. 69 examples were built at Boeing's Wichita, Kansas facility, with the remainder being built in the main Boeing plant in Seattle. The Wichita plant had originally been owned by the Stearman Aircraft Company but had been acquired by Boeing in 1934 and became a Boeing division in 1939. It had been used during World War 2 as an inland site for B-29 manufacture. The decision to shift B-52 production from Seattle to Wichita was a result of several factors. The commercial business at Seattle was picking up and Boeing needed more plant space to handle the orders. It so happened that there was a large, well-qualified work force already at hand in Wichita which was working on the B-47, the production of which was winding down.
The first contract for Wichita-built B-52D aircraft was AF33(600)-26235, which was concluded on November 29, 1954. Two serial number batches were assigned to these planes--55-0049/0067 and 55-0673/0680. A second contract, AF33(600)-31155, finalized on January 31, 1956, covered 42 more Wichita-built B-52Ds. Serials were 56-06567/0698.
An initial batch of 50 Seattle-built B-52Ds was ordered by contract AF33(600)-28223, which was finalized on August 31, 1954. Serials were 55-0068/0117. AF33(600)-31267 signed on October 26, 1955 covered 51 more Seattle-built B-52Ds. Serials were 65-0580/0630.
Seattle and Wichita used completely different schemes for their company serial numbers. Wichita's first B-52 bore the company number of 464001, where 464 stood for the model number and 001 meant that it was the first B-52 example coming off the production line. Seattle's B-52s c/n started with 16248 for the XB-52 and ended with 17467. The difference is greater than the total number of 277 B-52s built at Seattle due to other Boeing models such as the KC-135 being built concurrently at Seattle.
It was a Wichita-built aircraft which was the first B-52D to fly, on May 14, 1956. The first Seattle-built B-52D took off on its initial flight on September 28, 1956. The first B-52Ds reached SAC in the fall of 1956. The first few went to the 42nd Bombardment wing at Loring AFB, replacing the wing's initial B-52Cs. By the end of December 1956, several B-52Ds had been delivered to the 93rd Bombardment Wing.
There were problems with fuel leaks, with icing of the fuel system, and with malfunctions of the water injection pumps. The problem with the water injection pumps was eventually traced to the fact that the pumps would still keep operating even after the water tanks were empty. Installation of water sensors was the answer.
In 1959, SAC was faced with the growing capability of Soviet air defenses, and it was concluded that high-altitude operations with the B-52 would be increasingly hazardous in the future. The answer was to switch to low-altitude operations, where the B-52 would be much harder to detect and where Soviet defenses were known to be far less reliable. Although the B-52 was originally designed for high-altitude operations, all B-52s except for the early B-52Bs would now have to be capable of penetrating enemy defenses at altitudes as low as 500 feet. These low altitude B-52Ds were to be fitted with the ability to carry Hound Dog cruise missiles and Quail decoys, originally to have been carried only by the B-52G and H.
At first sight, the low-level modifications to the B-52D appeared to be fairly straightforward, including the improvement of the aircraft's bombing/navigation system, modification of the Doppler radar, and the addition of a terrain clearance radar. Low-altitude altimeters had to be acquired. The project rapidly became more complicated, since different B-52 models had to be accommodated. Airframes had to be strengthened, and the low-level structural modifications required for each B-52C and D were almost twice as costly as those that were required for any other B-52. The development of special terrain clearance radars proved more difficult than expected.
An AN/ALQ-27 electronic countermeasures system was to be fitted, which would, it was hoped, allow the B-52 to counter Soviet missiles and airborne fire control systems as well as early warning and ground control interception radars. However, the AN/ALQ-27 system was cancelled as being too complex and costly. In its place was a Quick Reaction Capability (QRC) package that was installed in new-build B-52Hs and retrofitted to earlier versions. The program was known as Big Four or "Mod 1000", and was carried out between November 1959 and September 1963.
The ECM improvements were to take place in several phases. Phase I was an emergency modification that provided the necessary minimum ECM equipment to counter the Soviet radar and surface-to-air missile threat. Phase II was essentially an ECM retrofit that was included in the Big Four package. The best available ECM equipment, comparing favorably to the cancelled AN/ALQ-27 system, was installed in Phase III.
As part of the switch from high-level to low-level missions, a lot of structural fixes had to carried out in order to prevent fatigue cracks from resulting in catastrophic failures. The first phase took place as each aircraft reached its 2000 flying hour mark and involved strengthening of the fuselage bulkhead and aileron bay plus reinforcement of boost pump panels and wing foot splice plates. Phase II was invoked when the aircraft reached its 2500 hour mark and involved repairs and reinforcements to upper wing splices inboard of the inner engin pods, lower wing panels supporting inner and outer engine pods, upper wing surface fuel probe access doors and the lower portion of the fuselage bulkhead. Phase III was an IRAN (Inspect and Repair As Necessary) project that dealt with wing cracks.
Less than 6 months after the B-52F became involved in combat in Vietnam, the Air Force decided to convert most of its B-52Ds to conventional warfare capability for service in Southeast Asia. Foremost among the changes needed was to give the B-52D the ability to carry a significantly larger load of conventional bombs. This led to the Big Belly project which was begun in December of 1965. The project increased the internal bomb capacity from just 27 weapons to a maximum of 84 500-lb Mk 82 or 42 750 lb M117 conventional bombs. This was done by careful rearrangement of internal equipment, and did not change the outside of the aircraft. In addition, a further 24 bombs of either type could be carried on modified underwing bomb racks (originally designed for the carrying of Hound Dog cruise missiles and fitted with I-beam rack adapters and a pair of multiple ejection racks), bringing the maximum payload to 60,000 pounds of bombs, about 22,000 pounds more than the capacity of the B-52F.
During 1967-1969, the B-52Ds assigned to conventional warfare missions in Southeast Asia were given a set of electronic warfare updates. This was done under a program known as Rivet Rambler or Phase V ECM fit. This involved the fitting of one AN/ALR-18 automated set-on receiving set, one AN/ALR-20 panoramic receiver set, one AN/APR-25 radar homing and warning system, four AN/ALT-6B or AN/ALT-22 continuous wave jamming transmitters, two AN/ALT-16 barrage-jamming systems, two AN/ALT-32H and one AN/ALT-32L high- and low-band jamming sets, six AN/ALE-20 flare dispensers (96 flares) and eight AN/ALE-24 chaff dispensers (1125 bundles).
Camouflage paint in tan and two shades of green, still with white undersides, was applied to B-52s in 1965, at the same time when other USAF aircraft were adopting camouflage. B-52Ds assigned to combat duty in Vietnam were painted in a modified camouflage scheme, with the undersides, lower fuselage, and both sides of the vertical fin being painted in a glossy black. The USAF serial number was painted in red on the fin.
Serials of B-52D:
55-0049/0051 Boeing B-52D-1-BW Stratofortress c/n 464001/464003 55-0052/0054 Boeing B-52D-5-BW Stratofortress c/n 464004/046006 55-0055/0060 Boeing B-52D-10-BW Stratofortress c/n 464007/464012 55-0061/0064 Boeing B-52D-15-BW Stratofortress c/n 464013/464016 55-0065/0067 Boeing B-52D-20-BW Stratofortress c/n 464017/464019 55-0068/0088 Boeing B-52D-55-BO Stratofortress c/n 17184/17204 55-0089/0104 Boeing B-52D-60-BO Stratofortress c/n 17205/17220 55-0105/0117 Boeing B-52D-65-BO Stratofortress c/n 17221/17233 55-0673/0675 Boeing B-52D-20-BW Stratofortress c/n 464020/464022 55-0676/0680 Boeing B-52D-25-BW Stratofortress c/n 464023/464027 56-0580/0590 Boeing B-52D-70-BO Stratofortress c/n 17263/17273 56-0591/0610 Boeing B-52D-75-BO Stratofortress c/n 17274/17293 56-0611/0630 Boeing B-52D-80-BO Stratofortress c/n 17294/17313 56-0657/0668 Boeing B-52D-30-BW Stratofortress c/n 464028/464039 56-0669/0680 Boeing B-52D-35-BW Stratofortress c/n 464040/464051 56-0681/0698 Boeing B-52D-40-BW Stratofortress c/n 464052/464069Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
Service Of The B-52D
By Joe Baugher
The first B-52Ds reached SAC in the fall of 1956. The first few went to the 42nd Bombardment wing at Loring AFB, replacing the wing's initial B-52Cs. By the end of December 1956, several B-52Ds had been delivered to the 93rd Bombardment Wing.
There were problems with fuel leaks, with icing of the fuel system, and with malfunctions of the water injection pumps. The problem with the water injection pumps was eventually traced to the fact that the pumps would still keep operating even after the water tanks were empty. Installation of water sensors was the answer.
On September 26, 1958, two B-52Ds of the 28th Bombardment Wing based at Ellsworth AFB in South Dakota established world speed records over two different routes. One B-52D flew at 560.705 mph for 10,000 kilometers in a close circuit without payload; the other at 597.675 mph for 5000 kilometers, also in a closed circuit without payload.
Less than 6 months after the B-52F became involved in combat in Vietnam, the Air Force decided to convert most of its B-52Ds to conventional warfare capability for service in Southeast Asia. Foremost among the changes needed was to give the B-52D the ability to carry a significantly larger load of conventional bombs. This led to the Big Belly project which was begun in December of 1965. The project increased the internal bomb capacity from just 27 weapons to a maximum of 84 500-lb Mk 82 or 42 750 lb M117 conventional bombs. This was done by careful rearrangement of internal equipment, and did not change the outside of the aircraft. In addition, a further 24 bombs of either type could be carried on modified underwing bomb racks (originally designed for the carrying of Hound Dog cruise missiles and fitted with I-beam rack adapters and a pair of multiple ejection racks), bringing the maximum payload to 60,000 pounds of bombs, about 22,000 pounds more than the capacity of the B-52F.
B-52Ds of the 28th and 484th Bomb Wings deployed to Guam in March and April of 1966, replacing the B-52Fs. Over the next few years, 11 more B-52D wings were rotated to combat duty in Southeast Asia. These included the 7th BW, 22nd BW, 70th BW, 91st BW, 92nd SAW, 96th SAW, 99th BW, 306th BW, 454th BW, 461st BW, and 509th BW. SAC crews who ordinarily would have been assigned to the B-52G or H models were sent through an intensive two-week course on the B-52D, making them eligible for duty in Southeast Asia. The program was known as Arc Light. While on duty at Andersen AFB, the B-52Ds were assigned to the 4133rd Bomb Wing (Provisional), which had been established on February 1, 1966. Some wings actually completed three tours of duty in support of the Vietnam war.
During 1967-1969, the B-52Ds assigned to conventional warfare missions in Southeast Asia were given a set of electronic warfare updates. This was done under a program known as Rivet Rambler or Phase V ECM fit. This involved the fitting of one AN/ALR-18 automated set-on receiving set, one AN/ALR-20 panoramic receiver set, one AN/APR-25 radar homing and warning system, four AN/ALT-6B or AN/ALT-22 continuous wave jamming transmitters, two AN/ALT-16 barrage-jamming systems, two AN/ALT-32H and one AN/ALT-32L high- and low-band jamming sets, six AN/ALE-20 flare dispensers (96 flares) and eight AN/ALE-24 chaff dispensers (1125 bundles).
Camouflage paint in tan and two shades of green, still with white undersides, was applied to B-52s in 1965 when other USAF aircraft were adopting camouflage. B-52Ds assigned to combat duty in Vietnam were painted in a modified camouflage scheme with the undersides, lower fuselage, and both sides of the vertical fin being painted in a glossy black. The USAF serial number was painted in red on the fin.
In the spring of 1967, B-52Ds were sent to U Tapao Airfield in Thailand, from which they were able to complete their missions without in-flight refueling. U Tapao was initially more of a forward field than it was a main operating base, with responsibility for scheduling missions still remaining on Guam. Small numbers of aircraft were drawn from each SAC B-52D unit to support the effort in Thailand, which was vested in the 4258th Strategic Wing. By 1970, U Tapao had assumed sole responsibility for the Arc Light campaign and was home for over 40 B-52s, and it became a main operating base with a much greater degree of self-sufficiency. On April 1, 1970, the 4258th SW was inactivated and reactivated as the 307th SW at U-Tapao with no change in personnel or mission.
On February 16, 1968, the first B-52 Arc Light missions were flown out of Kadena AB on Okinawa, inaugurating a 30-month period in which three bases were involved in the B-52 effort in Southeast Asia.
The B-52D effort was concentrated primarily against suspected Viet Cong targets in South Vietnam, but the Ho Chi Min Trail and targets in Laos were also hit. During the relief of Khe Sanh, unbroken waves of six aircraft, attacking every three hours, dropped bombs as close as 900 feet from friendly lines.
Cambodia was increasingly bombed by B-52s from March 1969 onward. These Cambodian bombing raids, one of the first acts of the new Nixon administration, were initially kept secret, and both SAC and Defense Department records were falsified to report that the targets were actually in South Vietnam. The Cambodian raids were actually carried out at night under the direction of ground units using the MSQ-77 radar, which guided the bombers to the release point and told them the precise moment to release their bombs. This made the deception easier, since even the crew members aboard the bombers did not have to know what country they were bombing. However, the specific flight coordinates (longitude and latitude) of the points of bomb release were noted in the navigator's logs at the end of each mission, and a simple check of the map could tell the crews which country they were bombing. Most of the crews must have known what was going on.
There were even attacks on North Vietnam itself, although at first only the very southernmost part near the Demilitarized Zone was hit. The B-52s generally avoided North Vietnamese airspace at this stage in the war, lest one of them fall victim to a SAM, which would have been a propaganda coup for North Vietnam and extremely embarrassing to the Defense Department.
On March 30, 1972, North Vietnamese forces began a massive invasion of South Vietnam, supported by artillery and tanks. On April 2, air strikes against the North Vietnamese attack were authorized under the name Freedom Train. At first, these strikes were in support of the South Vietnamese forces, but later the restrictions against attacking North Vietnam were lifted and the effort changed to that of the interdiction of supply lines. The first of these raids against the North was a raid by 15 B-52Ds on railway yards and oil storage facilities at Vinh. Three days later, the airfields at Bai Thuong were hit. On the weekend of 15-16 April, targets near Hanoi and Haiphong were attacked. By mid-April, virtually all of North Vietnam had been cleared for bombing raids, for the first time in more than 3 years. On May 10, the name of the operation against North Vietnam was changed to Linebacker.
In April 1972 B-52Gs joined the effort. The B-52G was not nearly as well suited for combat duty in Southeast Asia as was the B-52D, since it could not carry bombs externally and did not have the Big Belly modifications that gave the D such tremendous bomb-carrying capability. In addition, the B-52G did not have as good an electronic countermeasures suite as the B-52D, and the tail gunner of the B-52D was particularly effective in being able to monitor SAM launches from the rear.
In the meantime, negotiations were underway in Paris between National Security Advisor Henry Kissinger and North Vietnamese leader Le Duc Tho, trying to establish some sort of framework under which the US could withdraw from an increasingly unpopular war and still leave some sort of military parity between North and South Vietnam. On October 23, progress in the peace talks in Paris led the US to call off all air operations above the 20th parallel, which put Hanoi and Haiphong off-limits. This effectively halted Linebacker. Unfortunately, this gave the North Vietnamese a breathing spell in order to strengthen their defenses and repair the damage to their key lines of communication.
On November 22, the first B-52 combat loss took place. B-52D serial number 55-0110 flying out of U-Tapao was hit by a SAM during a raid on Vinh. The damaged aircraft was able to nurse its way back to Thailand, but the crew were forced to abandon their bomber before reaching base. The was the first B-52 to be destroyed by hostile fire in more than seven years of operation.
By early December of 1972, it was clear that the Paris peace talks were going nowhere, and President Richard Nixon decided that more drastic means were necessary. He ordered a new, full-scale aerial assault on North Vietnam in order to bring "peace with honor", as it was known in those days. The code name for the assault was Linebacker II. Air bases, missile sites, oil storage facilities, ammunition dumps and railroad networks would be struck. For the first time, targets in and around Hanoi and Haiphong would be attacked by the B-52s.
The first Linebacker II raid was on December 18, 1972, an attack on North Vietnamese fighter bases at Kep, Hoa Lac and Phuc Yen, plus the railhead at Yen Vien and the warehouse and storage complex at Kinh No.
During the Linebacker II raids, strict rules of engagement were enforced to lessen the risk of hitting civilian areas, as well as to avoid striking areas where POWs were known to be housed. In addition, B-52s were prohibited from maneuvering to evade SAMs or fighters once they had passed the initial point and were approaching the bomb release point. Initially, losses were heavy, with three B-52s being lost on the first night, and no less than 6 on the second night. Several hundred SAMs were fired at B-52s during the 11 days of Linebacker II. Onboard ECM equipment provided some protection, but it was far from infallible. In the latter stages of Linebacker II, more attention was paid to SAM sites and suspected missile storage areas, and the loss rate began to decline.
Linebacker II ended on December 29, 1972, when North Vietnam returned to the conference table. By this time, the North Vietnamese were clearly at the mercy of the B-52s. Had the bombing continued, there would have been little danger from SAMs. During Linebacker II, a total of 729 B-52 sorties were flown, 34 targets were hit, 15,287 tons of bombs were dropped, 1600 military structures had been damaged or destroyed, 3 million gallons of petroleum had been destroyed, and about 80 percent of North Vietnam's electrical generating capacity had been knocked out.
15 B-52s were lost during Linebacker II, with 9 being B-52Ds and 6 B-52Gs. This corresponded to a loss rate of less than 2 percent of the sorties. All 15 of the B-52s lost in Linebacker were shot down by SAMs, and none by fighters or AAA. Five MiGs were claimed by B-52 tail gunners during Linebacker II, but only two of them were actually confirmed.. The B-52 raids seemed to have the desired effect of getting North Vietnam to negotiate seriously, and on January 21, the agreement ending the American role in the war took effect on January 23, 1973. American POWs were released in March.
After Linebacker II, the B-52s returned to Arc Light missions. The last such mission took place on August 15, 1973. All the B-52s were withdrawn from Southeast Asia shortly thereafter.
On December 8, 1965, Secretary of Defense Robert S. McNamara had announced a long-term phase-out program involving several versions of the B-52 and their replacement by the General Dynamics FB-111A. Under the original plan, all remaining B-52C, D, E, and F aircraft were to be gone by the middle of 1971. However, because of the demands of the Vietnam War, the B-52D lasted much longer than expected, remaining in service several years after most of the other "tall-tailed" Stratofortresses had been retired. The B-52D fleet remained virtually intact until late 1978, when 37 examples were retired to storage at Davis-Monthan AFB. The final phaseout of the B-52D took place in 1982/83 when over 50 were sent to storage. Several were sent to join museum collections across America and even overseas.
The following outfits flew the B-52D:
7th Bombardment Wing (Heavy), Carswell AFB, Texas
9th Bombardment Squadron 1971-1982. Reactivated 1971 with B-52D
20th Bombardment Squadron 1969-1983
22nd Bombardment Wing (Heavy), March AFB, California
2nd Bombardment Squadron 1966-1982
486th Bombardment Squadron (from 340 BW)
28th Bombardment Wing (Heavy), Ellsworth AFB, South Dakota
77th Bombardment Squadron 1957-1971
717th Bombardment Squadron 1957-1960. Reassigned to 5245 SW at Sheppard AFB in 1960
718th Bombardment Squadron 1957-1960. Reassigned to 4128 SW at Amarillo AFB, Texas in 1960
42nd Bombardment Wing (Heavy), Loring AFB, Maine
69th Bombardment Squadron 1957-1959
70th Bombardment Squadron 1957-1959
75th Bombardment Squadron 1957-1959. Reassigned to 4039 SW with B-52G in 1959
43rd Strategic Wing, Andersen AFB, Guam
60th Bombardment Squadron, 1972-1983
63rd Bombardment Squadron (Provisional), 1972-1973
70th Bombardment Wing (Heavy), Clinton-Sherman AFB, Oklahoma
6th Bombardment Squadron 1968-1969. Inactivated 12/31/69.
91st Bombardment Wing (Heavy), Glasgow AFB, Montana
322nd Bombardment Squadron 1963-1968. Inactivated 6/25/68
92nd Bombardment Wing (Heavy), Fairchild AFB, Washington
325th Bombardment Squadron, 1957-1971
326th Bombardment Squadron, 1957-1961. Reassigned in 1961 to 4141st Strategic Wing at Glasgow AFB.
327th Bombardment Squadron, 1957-1961. Reassigned in 1961 to 4170th Strategic Wing at Larson AFB.
93nd Bombardment Wing (Heavy), Castle AFB, California
328th Bombardment Squadron, 1956-1958 and 1965-1974
329th Bombardment Squadron, 1956-1958 and 1965-1971
330th Bombardment Squadron, 1956-1958
96th SAW, Dyess AFB, Texas - redesignated 69th BW(H) 3/31/72
337th Bombardment Squadron, 1969-1982
99th Bombardment Wing, Westover AFB, Massachusetts
346th Bombardment Squadron, 1957-1961 and 1966-1972
347th Bombardment Squadron, 1957-1961. Reassigned in 1961 to 4047th SW at McCoy AFB, Florida
348th Bombardment Squadron, 1957-1961 and 1966-1972. Inactivated 9/30/73
306th Bombardment Wing (Heavy), McCoy AFB, Florida
367th Bombardment Squadron, 1963-1973. Acquired assets of 347 BS/4047 SW. Inactivated 7/1/74
307th Strategic Wing, U-Tapao AB, Thailand
Inactivated 9/30/75. Direct Wing control 1970-73 - replaced 4258 SW
364th Bombardment Squadron (Provisional), 1973-1975
365th Bombardment Squadron (Provisional), 1973-1974. Disbanded 7/17/74
340th Bombardment Wing (Heavy), Bergstrom AFB, Texas
486th Bombardment Squadron 1963-1966. Acquired assets of 335 BS/4130 SW. To 22 BW
376th Strategic Wing, Kadena AB, Okinawa.
Direct wing control 1970 - replaced 4252 SW. *Arc Light* missions from this base terminated 9/70.
454th Bombardment Wing (Heavy), Columbus AFB, Mississippi
736th Bombardment Squadron, 1966-1969. Inactivated 7/2/69
461th Strategic Wing (Heavy), Amarillo AFB, Texas, Inactivated 3/25/68
764th Bombardment Squadron, 1963-1968. Acquired B-52Ds previously with 718 BS/4128 SW. Inactivated 3/25/68
462nd SAW, Larson AFB, Washington - inactivated 6/25/66
768 Bombardment Squadron, 1963-1966. Acquired B-52Ds previously with 327 BS/4170 SW. Inactivated 4/2/66
484th Bombardment Wing (Heavy), Turner AFB, Georgia - Inactivated 3/15/67
824th Bombardment Squadron, 1963-1967. Took over assets of 336 BS/4138 SW. Inactivated 1/25/67
494th Bombardment Wing (Heavy), Sheppard AFB, Texas - inactivated 4/2/66
864th Bombardment Squadron, 1963-1966. Acquired B-52Ds previously operated by 717 BS/4245 SW Inactivated 4/2/66
509th Bombardment Wing (Heavy), Pease AFB, New Hampshire
393rd Bombardment Squadron, 1966-1969 - Switched to FB-111A in 1970.
4047th Strategic Wing, McCoy AFB, Florida - Inactivated 4/1/63
347th Bombardment Squadron, 1961-1963. Inactivated 4/1/63, assets to 367 BS/306 BW
4128th Strategic Wing, Amarillo AFB, Texas - Inactivated 2/1/63
718th Bombardment Squadron, 1960-1963. Inactivated 2/1/63, assets to 764 BS/461 BW
4130th Strategic Wing, Bergstrom AFB, Texas - Inactivated 9/1/63
335th Bombardment Squadron, 1959-1963. Inactivated 9/1/63, assets to 486 BS/340 BW
4138th Strategic Wing, Turner AFB, Georgia - Inactivated 2/1/63
336th Bombardment Squadron, 1959-1963. Inactivated 2/1/63, assets to 824 BS/484 BW
4141st Strategic Wing, Glasgow AFB, Montana - Inactivated 2/1/63
326th Bombardment Squadron, 1959-1963. Inactivated 2/1/63, assets to 322 BS/91 BW
4170th Strategic Wing, Larson AFB, Washington - Inactivated 2/1/63
327th Bombardment Squadron, 1960-1963. Inactivated 2/1/63, assets to 768 BS/462 BW
4245th Strategic Wing, Sheppard AFB, Texas - Inactivated 2/1/63
717th Bombardment Squadron, 1960-1963. Inactivated 2/1/63, assets to 864 BS/494 BW
4252nd Strategic Wing, Kadena AB, Okinawa
Possible that it exercised operational control over the B-52Ds at Kadena from 2/68. Inactivated 4/1/70 and replaced by 376 SW
4258th Strategic Wing, U-Tapao AB, Thailand
Possible that it exercised operational control over the B-52Ds at U-Tapao from 4/67. Inactivated 4/1/70 and reorganized as 307 SW
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
E-mail from RJT on history of inactivation of 4258th and more details about Cambodian bombing program.
The B-52E
Click on Picture to enlarge
The B-52E was a slightly improved version of the B-52D. The -E model was virtually identical to the -D in outward appearance. Most of the improvements were to internal systems. A new bomb navigation system and an improved doppler radar system were the major avionics upgrades.
The first of 100 B-52E's ordered was completed in October 1957. The first flight was on the roll out date, in part, because the -E model was so similar to the -D, there was no need for an extensive ground test program. Boeing and the USAF also used the concurrent rollout/first flight for public relations purposes.
Initial deployment of the B-52E, in late 1957, was to the 6th Bomb Wing stationed at Walker AFB. Improvements in surface-to-air missile technology during the late 1950s made high level penetration of enemy airspace increasingly dangerous. Because of this threat, B-52 combat tactics began to change from high-level penetration missions to stand-off weapons delivery.
The AGM-28 "Hound Dog" missile was the primary air-to-ground missile used beginning in the late 1950s. Two AGM-28s were carried on wing pylons mounted between the fuselage and inboard engine nacelles.
On a typical mission, an AGM-28 would be launched at an altitude of 45,000 feet, climb to over 56,000 feet, cruise to the target area, and then dive to the target. The missile has a range of more than 600 miles, allowing "standoff" launch hundreds of miles from the target, thus reducing the risk to the launch aircraft.
The B-52E remained in operational frontline service until the early 1970s when the last aircraft were phased out in favor of more modern models.
TYPE
B-52ENumber Built/Converted
100Remarks
Improved -D model
Notes:
Serial numbers: 56-0631 to 56-0656; 56-0699 to 56-0712; 57-0014 to 57-0029; 57-0095 to 57-0138
Boeing Model 464-259
First flight: 3 October 1957
B-52D Photo Gallery
Click on Picture to enlarge
|
The B-52E |
By Joe Baugher
The next production version of the Stratofortress was the B-52E (Model 464-259). The B-52E was externally identical to the B-52D which preceded it. The differences were entirely internal, and most of them were related to the need to adapt the Stratofortress to the low-level bombing role. This type of mission required a more sophisticated suite of bombing and navigation avionics, and led to the development of the AN/ASQ-38 system which was fitted to the B-52E and to subsequent Stratofortress versions. In the B-52E, some internal equipment was relocated and a slight redesign of the navigator-bombardier station increased crew comfort.
With the B-52E, the second-source production line at Wichita began to assume the leading role in Stratofortress manufacture, producing 58 aircraft, while the Seattle facility produced 42.
The B-52E procurement was covered in four separate contracts, funded in fiscal years 1956 and 1957:
AF33(600)-31155 signed on August 10, 1955, covered 14 Wichita-built B-52Es. Serials were 56-0699/0712.
AF33(600)-31267 signed on October 26, 1955 was originally a B-52D contract, but 26 Seattle-built B-52Es were also included. These serials were 56-0631/0656.
AF33(600)-32863 signed on July 2, 1956 covered 16 Seattle-built B-52Es. Serials were 57-0014/0029.
The final contract which included B-52Es was AF33(600)-32864, signed on July 2, 1956. It included 44 Wichita-built B-52Es, serialed 57-0095/0138.
The first B-52E (a Seattle-built machine) flew for the first time on October 3, 1957. Wichita's first B-52E took off on its maiden flight on October 17, 1957. 100 B-52Es were accepted by the USAF between October 1957 and June 1958. The first B-52Es entered service with SAC in December of 1957.
The AN/ASQ-38 bombing and navigation system introduced on the B-52E was devised by the Military Products Division of IBM. It was a hard- wired analog integrated system consisting of four parts:
MD-1 automatic astrocompass
AN/AJA-1 or AN/AJN-8 true heading computer system
AN/APN-89A Doppler radar
AN/ASB-9A or AN/ASB-16 bombing navigation system
It was designed for a high degree of automatic operation. The Doppler radar fed ground speed and drift information into the AN/ASB-16. Latitude/longitude information was supplied to the true heading computer and to the astrocompass.
The new ASQ-38 bombing/navigation system was at first not as accurate as had been anticipated and was difficult for ground crews to maintain. Extensive engineering changes were needed to improve its low-level terrain avoidance capability. In the late 1950s, a program known as Jolly Well was launched to bring the ASQ-38 system of the B-52E, F, G, and H models up to standards, and was not completed until 1964 after it had involved no less than 480 aircraft.
The second B-52E (56-0631 was assigned from the start to major test programs. It was used for prototyping landing gears, engines, and other major subsystems. The test aircraft later underwent permanent modifications in order to carry out specialized development projects and was re-designated NB-52E. The aircraft was intended to study electronic flutter and buffeting suppression systems, because several B-52s had been lost due to structural failures caused by aerodynamic stresses while flying at low level. Small swept winglets were attached alongside the nose, and a long probe extended from the nose. The wings was fitted with twice the number of control surfaces, and the traditional mechanical and hydraulic linkages that moved the control surfaces were replaced by electronic systems. To support its research mission, the interior of the NB-52E was loaded with measuring instrumentation. The NB-52E later participated in the Load Alleviation and Mode Stabilization (LAMS) project. Wind gusts were detected and measured by a battery of sensors, which activated the control surfaces accordingly to cut down on the amount of fatigue damage to the structure of the aircraft. In mid-1973, the NB-52E flew ten knots faster than the speed at which flutter normally would have disintegrated the aircraft.
57-0119 also used the NB-52E designation. This aircraft was assigned to General Electric and was used as a flying testbed for the XTF99 turbofan, which replaced the starboard inner pair of J57 turbojets.
Specification of Boeing B-52E Stratofortress
Engines: Eight Pratt & Whitney J57-P-29WA or -19W turbojets, each rated at 10,500 lb.s.t dry and 12,100 lb.s.t. Performance: Maximum speed 630 mph at 19,800 feet, 570 mph at 45,050 feet. Cruising speed 523 mph. Stalling speed 169 mph. Initial climb rate 5125 feet per minute. Service ceiling at combat weight 46,200 feet. Combat radius 3500 miles with 10,000 pound bombload. Ferry range 7875 miles. Takeoff ground run 8000 feet. Takeoff over 50-foot obstacle in 10,300 feet. Dimensions: Length 156 feet 6.9 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 174,782 pounds empty, 292,460 pounds combat, 450,000 pounds maximum takeoff. Armament: Four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 43,000 pounds.
Serials of B-52E:
56-0631/0649 Boeing B-52E-85-BO Stratofortress c/n 17314/17332 56-0650/0656 Boeing B-52E-90-BO Stratofortress c/n 17333/17339 56-0699/0712 Boeing B-52E-45-BW Stratofortress c/n 464070/464083 57-0014/0022 Boeing B-52E-90-BO Stratofortress c/n 17408/17416 57-0023/0029 Boeing B-52E-95-BO Stratofortress c/n 17417/17423 57-0095/0109 Boeing B-52E-50-BW Stratofortress c/n 464084/464098 57-0110/0130 Boeing B-52E-55-BW Stratofortress c/n 464099/464119 57-0131/0138 Boeing B-52E-60-BW Stratofortress c/n 464120/464127Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
|
Service Of The B-52E |
By Joe Baugher
100 B-52Es were accepted by the USAF between October 1957 and June 1958. The first B-52Es entered service with SAC in December of 1957.
The B-52E served with the following units:
6th Bombardment Wing, Walker AFB, New Mexico -
redesignated 6 SAW 5/1/62
24th Bombardment Squadron 1957-1967 - inactivated
12/5/67
39th Bombardment Squadron 1957-1963 - Inactivated
9/15/63
40th Bombardment Squadron 1957-1967 - inactivated
1/25/67
4129th CCTS 1959-1963 - inactivated 9/15/63
11th Bombardment Wing, Altus AFB, Oklahoma -
Redesignated 11 SAW 4/1/63
26th Bombardment Squadron 1958-1968 - inactivated
7/2/68
42nd Bombardment Squadron 1958-1960--reassigned to 4043 SW 6/1/60
17th Bombardment Wing, Wright-Patterson AFB, Ohio
34th Bombardment Squadron 1963-1968--replaced 42 BS/4043 SW
70th Bombardment Wing, Clinton-Sherman AFB, Oklahoma
6th Bombardment Squadron 1963-1968 -- replaced 98 BS/4123 SW
93rd Bombardment Wing, Castle AFB, California
328th Bombardment Squadron 1957-58 and 1967-70
329th Bombardment Squadron 1957-58 and 1967-70
330th Bombardment Squadron 1957-58
96th Strategic Air Wing, Dyess AFB, Texas
337 Bombardment Squadron 1963-70
4043 Strategic Wing, Wright-Patterson AFB, Ohio --
Inactivated 2/1/63
42nd Bombardment Squadron 1960-63 --assets to 34 BS/17 BW
4123 Strategic Wing, Clinton-Sherman AFB, Oklahoma --
Inactivated 2/1/63
98 Bombardment Squadron 1959-63 -- assets to 6 BS/70 BW
The B-52E never served in the Southeast Asia war. A few worn-out B-52Es were withdrawn from service in 1967, but the majority of the B-52Es were phased out of SAC service and consigned to storage during 1969/70.
Sources:
American Combat Planes, Third Enlarged Edition, Ray
Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack,
Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval
Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon
Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne,
Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
|
The JB-52E |
Click on Picture to enlarge
Two B-52Es were modified for use as engine testbeds. One aircraft (B-52E-55-BW S/N 57-0119) was used to test the General Electric TF-39 for the Lockheed C-5A "Galaxy" program. The TF-39 was mounted on the right inboard engine pylon in place of the two J57s normally installed. The single TF-39 turbofan, rated at about 40,000 lbs., had as much thrust as four J57 turbojets on a standard production B-52E.
Another aircraft (B-52E-85-BO S/N 56-0636) was similarly modified to test the JT9D turbofan engine for the Boeing 747 program.
Various design studies were done to investigate the feasibility of modifying the B-52 airframe for the large turbofan engine. The most common design called for a four engine configuration, but some had as many as eight engines. None of these designs were ever proceeded with; however, the B-52H did have upgraded TF-33 turbofan engines installed in place of the J57s. The TF-33 was much more powerful than the J57 it replaced, but nowhere near as powerful as the TF-39 or JT9D.
TYPE
JB-52ENumber Built/Converted
2 (cv)Remarks
Engine test bed aircraft
Notes:
Serial numbers: B-52E-85-BO 56-0636 & B-52E-55-BW 57-0119
56-0636 was used to test the Pratt & Whitney JT9D for the Boeing 747 program
57-0119 was used to test the General Electric TF-39 for the Lockheed C-5A program
B-52E Photo Gallery
Click on Picture to enlarge
| The NB-52E |
Click on Picture to enlarge
The second B-52E built (S/N 56-0632) was withheld from operational service and used for special test programs. The aircraft was redesignated NB-52E and used mostly for stability and control testing.
One program was named Control Configured Vehicles (CCV). The CCV program was conducted as a joint effort of Boeing and the Air Force Flight Dynamics Laboratory (AFFDL), and involved special modifications designed to reduce structural bending and control surface flutter in moderate to severe air turbulence. The NB-52E was fitted with three canard control surfaces (two horizontal and one ventral) which were linked to computers which in turn received flight data from sensors mounted throughout the aircraft. When the sensors, which included gyros and accelerometers, detected an abrupt change in vertical, horizontal, pitch, roll or yaw acceleration, a signal was transmitted to the on-board computers which used the canards and standard flight controls to dampen the effects of the turbulence. This system was collectively known as the Ride Control System (RCS) and was very effective in reducing the load effects of turbulence.
TYPE
NB-52ENumber Built/Converted
1 (cv)Remarks
Stability and control test aircraft
Notes:
Serial number: B-52E-85-BO 56-0632
Boeing NB-52E Photo Gallery
Click on Picture to enlarge
The B-52F
Click on Picture to enlarge
The B-52F was an updated version of the B-52E. The major improvement was to the powerplants. Pratt & Whitney J57-P-43W turbojets were used, each with a maximum thrust of 13,750 lbs. with water injection. These new engines had large alternators mounted on the left side which gave the -F model engine nacelles a distinctive bulge (an -F model is easily identified by the tall tail and the alternator fairings on the engine nacelles).
A total of 89 -F models were built, 44 at Boeing's Seattle plant and 45 at the Wichita plant. The Seattle plant ceased producing B-52s after the -F model when all production shifted to the Wichita plant.
The first flight of the B-52F was on 6 May 1958 when the first of the Seattle-built -F models took off (S/N 57-0030). The first flight of a Wichita-built B-52F occurred only 8 days later on 14 May. The B-52F entered operational service in June 1958 after a very short acceptance and test program.
The B-52F was used extensively in Southeast Asia (SEA) during the early stages of the conflict. In 1966, the -F models were withdrawn from combat operations in SEA and returned to the United States for nuclear deterrent duty. The aircraft remained in operational service until the last aircraft was retired in 1978.
TYPE
B-52FNumber Built/Converted
89Remarks
Improved -E model
Notes:
Serial numbers: 57-0030 to 57-0073 (Seattle built); 57-0139 to 57-183 (Wichita built)
Boeing Model Number 464-260
First flight was on 6 May 1958
B-52F Photo Gallery
Click on Picture to enlarge
The Service Of The B-52F By Joe Baugher
The B-52F (Model 464-260) differed from the E primarily in being equipped with more powerful J57-P-43W, -P-43WA, or P-43WB turbojets, which each offered a normal rating of 11,200 lb.s.t dry and 13,750 lb.s.t. with water injection. Incorporation of these new engines required some internal changes, and a slight modification had to be made to the wing structure in order to incorporate two additional water tanks in the wing.
The only noticeable external difference introduced on the F was the addition of a set of "hard-drive" alternators to supply electrical power to the aircraft. These units were attached to the left-hand side of each podded pair of engines. These replaced the often troublesome air-driven turbines and alternators that were located inside the fuselage on earlier B-52 versions. The air-driven turbines had on one occasion disintegrated, sending red-hot fragments into the fuselage fuel cells, causing a catastrophic fire and loss of the aircraft. The fitting of the new alternator required some redesign of the engine cowling cover, which produced a noticeable bulge on the lower left-hand side. There were small ram intakes cut into the lower lip of each engine air intake. These were intended to provide cooling air for engine oil and constant speed drive units.
There were two B-52F contracts. AF33(600)-32863 signed July 2, 1956 covered Seattle-built B-52Fs (as well as a small number of B-52Es). Serials were 57-0030/0073. AF33(600)-38264 signed on the same date covered 44 B-52Es and 45 B-52Fs, all of which were to built at Wichita. Serials of the B-52Fs were 57-0139/0183.
The first Seattle-built B-52F flew for the first time on May 6, 1958, with the first Wichita-built following eight days later. Seattle built 44, whereas Wichita built 45. This was to turn out to be the last B-52 version to be built at Seattle, all subsequent Stratofortresses being built solely at Wichita.
B-52F deliveries lagged a few months behind schedule because of fiscal restrictions imposed by the Defense Department in late 1957 that limited the amount of authorized overtime at Boeing. Consequently, B-52Fs did not start reaching SAC until June 1958, the 93rd Bomb Wing being the first recipient.
All 89 B-52Fs were accepted by the USAF between June 1958 and February 1959. After the delivery of the last B-52F from Seattle, the Seattle plant transferred all B-52 engineering responsibility to Wichita.
The first B-52Fs (as well as some preceding B-52s) had problems with fuel leaks. Marman clamps, the flexible fuel couplets that interconnected fuel lines between tanks, broke down on several occasions, creating a fire hazard. A September 1957 project known as *Blue Band* put new clamps on all B-52s, but these did not work very well and soon caused problems on their own. The aluminum clamps developed early signs of stress corrosion, indicating a high probability of failure in the near future, and another program knows as Hard Shell was instituted in which the aluminum clamps were replaced with stainless steel strap clamps. Hard Shell was completed in January of 1958, but the results were still not entirely satisfactory because of deficient latch pins. A new project known as Quickclip started in mid 1958 involved the installation of a safety strap around the modified clamps to prevent the fuel from leaking out. Additional B-52Fs entering the inventory after the fall of 1958 were also fitted with Quickclip safety straps.
Subsequent modifications gave the B-52F enhanced conventional warfare capability. In June of 1964, the Air Staff approved the modification of 28 B-52Fs under a project known as South Bay. They could carry 24 750-pound bombs externally. The bombs were carried on external pylons installed underneath each wing inboard of the inner engine pods. These pylons had originally been designed to carry the Hound Dog cruise missile. This essentially doubled the aircraft's conventional bombload, raising total bombload to 38.250 pounds. The expanding Vietnam war led Secretary of Defense Robert MacNamara to request that 46 other B-52Fs be similarly modified under a program known as Sun Bath.
Serials of B-52F:
57-030/037 Boeing B-52F-100-BO Stratofortress c/n 17424/17431 57-038/052 Boeing B-52F-105-BO Stratofortress c/n 17432/17446 57-053/073 Boeing B-52F-110-BO Stratofortress c/n 17447/17467 57-074/094 Boeing B-52F Stratofortress - all cancelled 57-139/154 Boeing B-52F-65-BW Stratofortress c/n 464128/464143 57-155/183 Boeing B-52F-70-BW Stratofortress c/n 464144/464172Specification of Boeing B-52F Stratofortress:
Engines: Eight Pratt & Whitney J57-P-43WA turbojets, each rated at 11,200 lb.s.t dry and 13,750 lb.s.t. with water injection. Performance: Maximum speed 638 mph at 21,000 feet, 570 mph at 46,500 feet. Cruising speed 523 mph. Stalling speed 169 mph. Initial climb rate 5600 feet per minute. Service ceiling at combat weight 46,700 feet. Combat radius 3650 miles with 10,000 pound bombload. Ferry range 7976 miles. Takeoff ground run 7000 feet. Takeoff run over 50-foot obstacle 9100 feet. Dimensions: Length 156 feet 6.9 inches, wingspan 185 feet 0 inches, height 48 feet 3.6 inches, wing area 4000 square feet. Weights: 173,599 pounds empty, 291,570 pounds combat, 450,000 pounds maximum takeoff. Armament: Four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 43,000 pounds.
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
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Service Of The B-52F |
By Joe Baugher
The first Seattle-built B-52F flew for the first time on May 6, 1958, with the first Wichita-built example following eight days later. Seattle built 44, whereas Wichita built 45. This was to turn out to be the last B-52 version to be built at Seattle.
B-52F deliveries initially lagged a few months behind schedule because of fiscal restrictions imposed by the Defense Department in late 1957 that limited the amount of authorized overtime at Boeing. Consequently, B-52Fs did not start reaching SAC until June 1958, the 93rd Bomb Wing being the first recipient.
All 89 B-52Fs were accepted by the USAF between June 1958 and February 1959. After the delivery of the last B-52F from Seattle, the Seattle plant transferred all B-52 engineering responsibility to Wichita.
The B-52F was the first Stratofortress model to participate in combat. B-52F aircraft taken from the 7th and 320th Bomb Wings were sent to bomb suspected Viet Cong enclaves in South Vietnam in June of 1965 under a program known as Arc Light. The B-52Fs were stationed at Andersen AB on Guam, the operation being supported by KC-135As stationed at Kadena AB on Okinawa.
The first raid was carried out from Guam by 30 B-52Fs on June 18, 1965 against an unseen Viet Cong target at Ben Cat, 40 miles north of Saigon. Prior to the mission, the crews were briefed that a minimum of 2000-3000 (possibly as high as 6000 or more) North Vietnamese regulars were encamped in the target area. To ensure security, it was planned that the raid would be carried out in complete radio silence from beginning to end. The raid did not start off well--on the way to the target, two B-52Fs collided in midair during a refueling operation and 8 crew members were killed. An investigation later blamed the cause for the mid-air collision on a combination of poor staff planning, extremely unusual and unique weather conditions, forbidden radio communications and an untested air refueling operation. The next day, the press back in the USA generally derided the raid as being an expensive and costly failure, and it was claimed that only one water buffalo was killed and only 100 pounds of rice were destroyed.
However, it seems that the results of the raid were a lot more effective than the press had led people to believe. All of the bombs were dropped into the correct target box, except for one string of bombs which had missed the area completely because of a radar failure. After about a week, teams began to enter the area and reported almost total destruction of all life in the area.
After the mission, morale was very low due to the loss of the eight crew members as well as the generally negative reports that had appeared in the press back in the USA about the effectiveness of the raid. Additional missions were cancelled and did not resume until July. There was initially some skepticism about the usefulness of a high-altitude radar bomb drop against guerilla forces. Nevertheless, within a few months there was universal acceptance of the power of the B-52 raids as a new type of artillery. By November of 1965, the B-52s were able to support the 1st Air Cavalry Division in mopping up operations near Pleiku.
There were no B-52F losses in actual combat, although two B-52Fs were destroyed when they collided in mid-air on their way to the first Arc Light mission.
In the spring of 1966, the B-52Fs were replaced by Big Belly B-52Ds and played no further part in the Vietnam War.
The following units operated the B-52F:
2nd Bombardment Wing - Barksdale AFB, Louisiana.
20 Bombardment Squadron 1963-1965 - acquired assets of 436 BS/4238 SW 4/1/63. Reassigned to 7 BW 6/25/65
7th Bombardment Wing, Carswell AFB, Texas
9 Bombardment Squadron, 1958-1968 - inactivated
6/25/68
20 Bombardment Squadron, 1965-1969 - transferred from 2 BW 6/25/65
93rd Bombardment Wing, Castle AFB, California
328 Bombardment Squadron 1958-1974
329 Bombardment Squadron 1958-1971
330 Bombardment Squadron 1958-1963 - inactivated 9/15/63
320th Bombardment Wing, Mather AFB, California
441 Bombardment Squadron 1963-1968 - acquired assets of 72 BS/4134 SW
454th Bombardment Wing, Colombus AFB, Mississippi
736 Bombardment Squadron 1963-1966 - acquired assets of 492 BS/4228 SW
4134th Strategic Wing, Mather AFB, California -
inactivated 2/1/63
72 Bombardment Squadron 1958-1963 - assets transferred to 441 BS/320 BW
4228th Strategic Wing, Columbus AFB, Mississippi -
Inactivated 2/1/63
492 Bombardment Squadron 1959-1063 - assets to 736 BS/454 BW
4238th Strategic Wing, Barksdale AFB, Louisiana -
Inactivated 1/4/63.
436 Bombardment Squadron, 1958-1963 - assets to 20 BS/2 BW
Several worn-out B-52Fs were retired in 1967-68, but most remained in services until well into the 1970s. The last B-52Fs were retired to storage between August and December of 1978.
Sources:
American Combat Planes, Third Enlarged Edition, Ray
Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack,
Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval
Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon
Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne,
Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress,
Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
E-mail from Jerry B. Hendrix on results of the first "Arc Light" mission. It was a lot more effective that most sources generally acknowledge.
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The B-52G |
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The B-52G was a designed to reduce the overall aircraft weight in an effort to improve performance. The most obvious change was the redesigned tail. About 8 feet of the vertical stabilizer was removed and the chord (width) was increased. The wing was extensively modified also. The seal-sealing bladder-type fuel cells were removed and the wing itself was sealed for fuel (wet wing). The tail gunner's position was moved from the tail turret to a remote firing station in the forward crew compartment.
Boeing (Wichita) built all 193 B-52G with the first aircraft rolling out of the production plant in the summer of 1958. The -G model was capable of carrying two AGM-28 "Hound Dog" missiles like the -F model, but it was also equipped to carry the GAM-87 "Skybolt" and later the Air Launched Cruise Missile (ALCM) and the Short Range Attack Missile (SRAM).
The B-52G was used extensively in the 1991 during operation Desert Storm before being phased out of operational service in 1994.
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TYPE B-52G |
Number Built/Converted 193 |
Remarks Improved -F model |
Notes:
Serial numbers: 57-6468 to 57-6520; 58-0158 to 58-0258; 59-2564 to 59-2602
Boeing Model Number 464-253
First flight was on 31 August 1958
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B-52G Photo Gallery |
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| The B-52G |
By Joe Baugher
The B-52G (Model 464-253) was the most numerous sub-type of the Stratofortress series, a total of 193 being built between October 1958 and February 1961. It was the first Stratofortess version to be built exclusively at the Wichita factory.
The B-52G design was officially begun in June of 1956. At that time, the Convair B-58 Hustler program seemed to be in trouble, and the development of the B-52G was initiated as a safety measure intended to prevent possible technical obsolescence of the strategic bomber force in the 1960s. As it turned out, the service of the B-52G far outlasted that of the B-58.
Thee were three separate orders for the B-52G:
AF33(600)-35992 finalized on May 15, 1958, covering 53 aircraft obtained with FY 57 funds with serials 57-6468/6520.
AF33(600)-36470 finalized May 15, 1958 covered 101 examples obtained with FY 58 funds. Serials were 58-158/258.
AF33(600) finalized April 28, 1959 calling for 39 aircraft obtained with FY 59 funds. Serials were 59-2564/2602.
In the design of the B-52G, considerable attention was paid to reducing the structural weight. Different materials were used in the construction of the airframe, and the wing structure was extensively redesigned. The most visible difference was a vertical tail which was reduced in size. The height was reduced from 48 feet 3 inches to 40 feet 7 inches. The new tail was tested on the first B-52A (52-001) and perhaps also on either the XB-52 or YB-52 before being adopted as standard for the B-52G.
The B-52G retained the J57-P-43W engines of the B-52F, but the engine's water injection system was improved in duration capability by adding a 1200-gallon tank of water in the forward fuselage.
In the B-52G, the gunner was moved from the extreme rear of the aircraft to a position beside the electronic warfare officer in the forward part of the fuselage. He was provided with a rearward-facing upward-firing ejector seat. The locations of the other four crew members (pilot, copilot, bombardier and radar navigator) were unchanged.
A new Avco-Crosley AN/ASG-15 fire control system was fitted in the extreme tail to support the now remotely-operated rearward-firing gun turret. Like earlier versions of the fire control system, the AN/ASG-15 featured separate radar dishes for search and track, but it also carried a television camera, although the camera was later replaced by ALQ-117 countermeasures gear. The gunner could operate the tail guns either by using the AGS-15 fire-control system or by using a remote control system which he monitored approaching threats either by radar or by closed-circuit television.
The ammunition capacity of the tail gun was altered. The removal of the rear gunner's position made it possible to move the stowage location for the braking parachute from below to above the extreme aft fuselage section.
In the design of the B-52G, considerable attention was paid to improvements in crew comfort. In previous B-52s, pilots had often roasted while the bombardier and radar navigator froze, leading to lots of arguments over the cabin temperature control setting. The seats were redesigned to lessen the fatigue of 20-hour missions.
The B-52G retained the AN/ASQ-38 bombing navigation system of the B-52F. However, the nose radome was enlarged, and was now of one-piece construction.
The B-52G featured a "wet" wing which resulted in it being able to carry 48,030 gallons of fuel as opposed to the 41,553 gallons of the B-52F. Each wing had three integral fuel tanks which replaced the rubber bladder-type tanks in the wings of previous versions. This called for a complete structural redesign. The new wing required the machining of long alloy wing skins so that stiffeners were an integral part of the structure. This resulted in a surface with a minimum of chordwise joints which, it was hoped, would reduce the possibility of fuel leaks and fatigue.
The new wing also saved weight by dispensing with the ailerons, relying entirely on the spoilers for lateral control. However, the elimination of the ailerons did have some unpleasant side effects. The missing ailerons, acting in conjunction with the shorter rudder, increased the tendency of the aircraft to Dutch roll, a problem with all large swept wing aircraft. The existing yaw damper was not adequate to correct this problem. The elimination of the ailerons also changed the lateral response--when a turn was initiated the spoilers that were raising up would often induce a slight buffet. The spoilers also induced a slight tendency for the nose to pitch-up when they were extended. This effect was particularly troublesome during aerial refuelling, where the lateral spoiler movement that was needed to keep station often produced a nose pitch-up. This motion was very fatiguing for the pilot to correct, and resulted in a later modification.
The familiar jettisonable 3000-gallon underwing auxiliary fuel tanks of earlier versions were replaced by smaller, fixed 700-gallon tanks. These were actually fitted not so much for the additional fuel capacity but more for their role as bob weights to help prevent wing flutter.
In spite of the weight reduction program, the gross weight of the B-52G was up to 488,000 pounds because of the increased fuel capacity. Total internal fuel tankage was 46,575 gallons. With the two external tanks fitted, total fuel capacity was 47,975 gallons. This offered greatly enhanced range performance.
The B-52G flew for the first time on August 31, 1958. The B-52G entered service with the 5th Bomb Wing at Travis AFB on February 13, 1959. In May, the 42nd Wing began to receive B-52Gs.
From the 55th B-52G onward (58-0159), ability to carry the North American GAM-77 (later re-designated AGM-28) Hound Dog air-launched cruise missile was added. An underwing pylon was added inboard of the inner engine pods underneath each wing, one Hound Dog being carried on each pylon. Earlier B-52Gs were upgraded by 1962 with Hound Dog capability, as well as some earlier B-52s. All versions from the B-52C onward are known to have carried the Hound Dog at some time in their careers.
The AGM-28 Hound Dog was 42 feet long with a wingspan of 12 feet. It was powered by by a single Pratt & Whitney J52-P-3 turbojet engine rated at 7500 lb.s.t. It had a maximum speed of Mach 2.1, and maximum range at high altitude was about 700 nautical miles, although this was reduced to 200 nautical miles when at low level. The Hound Dog was guided by an inertial system assisted by an astrotracker. The inertial guidance system was updated by the B-52's onboard system just before launch. Since the inertial guidance system relied on no external signals, it could not be jammed. The flight path could be profiled for tree top level or for altitudes as high as 55,000 feet. The AGM-28 carried a single W28 thermonuclear warhead, with a 1 megaton yield. The J52 jet engines of the AGM-28 could be used for extra power during takeoff, and the inertial navigation system of the AGM-28 could even be used as a backup for the B-52's own system.
The first Hound Dog-equipped B-52G unit was the 4135th Strategic Wing, based at Eglin AFB in Florida. This unit first deployed in December of 1959. At the peak in 1963, the Hound Dog force numbered 600. However, the weapon was not all that accurate, and its primary mission in the case of a nuclear war would probably have been to go ahead of the penetrating bombers to clear a path through enemy defenses. The Hound Dog rapidly became obsolete in the face of technological advances, the weapon being gradually withdrawn from service beginning in 1967. By the end of 1969, the number of missiles was down to 350. By the end of June 1975, the missile was finally taken off alert duty, but it remained on non-operational status for a while longer. The last AGM-28 was scrapped in June 1978, and the only ones left are now on display in museums.
The B-52G could also carry up to four McDonnell GAM-72 (later AGM-20) Quail decoy missiles internally in the extreme rear of the weapons bay. The GAM-72 decoy missile was designed to simulate the radar cross section, infrared signature, and flight profile of the B-52. This was done by careful use of radar reflectors, electronic repeaters, chaff, and infrared simulators. The Quail could be programmed to perform at least one change of cruising speed and two turns. The Quail was 12 feet 10.6 inches long, the wing span was 5 feet 4.5 inches, and the height was 3 feet 3.5 inches when the aerodynamic surfaces were deployed. The Quail was powered by a single General Electric J85-GE-7 turbojet. Maximum speed of the AGM-20 was Mach 0.85 and the range was 460 nautical miles when flying at 50,000 feet. When flying at 35,000 feet, maximum speed was Mach 0.8 and range was 393 nautical miles.
The Quails were carried in a folded configuration inside the weapons bay. At the time of launch, a retractable device lowered the decoys into the slipstream. The flying surfaces were deployed and the engine was started prior to launch on the command of the radar navigator. Any one or all the missiles could be jettisoned in the event of a malfunction, and it was possible to dump the entire package in the case of a major emergency.
Development of the GAM-72 was initiated back in October of 1952, when SAC issued a requirement for a decoy that could be deployed and launched from a bomber prior to penetrating enemy airspace. In February 1956, McDonnell was selected as the prime contractor. Flight trials of the XGAM-72 began in November 1958. A contract for production was awarded to McDonnell on December 31, 1958.
The first Quails began to join the 4135th Strategic Wing at Eglin AFB in late 1960. A total of 14 Stratofortress squadrons eventually received the Quail. The Quail was withdrawn in 1989, when a shortage of spares forced its retirement.
The B-52G had a lighter structure than previous versions in order to save weight, but it carried more fuel. This meant that fatigue problems resulting from the structural flexing generated by the stresses of low-level flying and midair refuelling manifested themselves earlier in the life cycle of the airframe. This was especially the case in the region of the wing structure where most of the weight savings had been achieved by using an aluminum alloy. Fatigue cracks got so bad that stringent flying restriction had to be imposed, pending modifications. In May of 1961, a program was approved in which the wings were modified and strengthened as part of the regular IRAN schedules for the aircraft in the B-52 fleet. The project was finally completed in September of 1964.
In 1970, the Air Force decided to equip the B-52Gs to carry the Boeing AGM-69A short-range attack missile (SRAM). This involved the addition of underwing pylons, launch gear, rotary launchers, and new avionics. These modifications began in October 1971, and the first SRAM-equipped B-52G entered service with the 42nd Bomb Wing in March of 1972. Each modified B-52G could carry up to 20 SRAMs, 12 externally on the underwing pylons and 8 on a rotary launcher inside the rear of the bomb bay. The SRAM was 14 feet long , 17.5 inches in diameter, and weighed about 2300 pounds. It was powered by a Thiokol SR-75-LP-1 re-startable solid-fuelled two-pulse rocket motor which gave a maximum speed of Mach 2.5. A General Precision/Kearfott inertial guidance system was fitted. The missile could be flow at either supersonic or subsonic speeds, and could follow either a high-altitude semi-ballistic trajectory or a low-altitude profile. It was designed to attack targets ahead of the launch aircraft or could turn in flight to attack installations to the side or behind the bomber. A 170 kiloton W69 nuclear warhead was carried.
External carriage of the SRAM was abandoned in the the early 1980s. Concerns over the continued safety of the warheads in the SRAM caused the weapon to be removed from the operational inventory in 1990.
During 1967-1969, some of the B-52Gs that had been assigned to conventional warfare missions were given the same set of electronic warfare updates as were assigned to the B-52D fleet. This was done under a program known as Rivet Rambler or Phase V ECM fit. This involved the fitting of one AN/ALR-18 automated set-on receiving set, one AN/ALR-20 panoramic receiver set, one AN/APR-25 radar homing and warning system, four AN/ALT-6B or AN/ALT-22 continuous wave jamming transmitters, two AN/ALT-16 barrage-jamming systems, two AN/ALT-32H and one AN/ALT-32L high- and low-band jamming sets, six AN/ALE-20 flare dispensers (96 flares) and eight AN/ALE-24 chaff dispensers (1125 bundles). Some of the B-52Gs that went through this upgrade program were also provided with AN/ALE-25 forward-firing chaff dispenser rocket pods suspended on pylons between the engine pods. Each pod was about 13 feet long and contained 20 Tracor AN/ADR-8 2.5-inch folding fin chaff rockets that could be fired either manually or automatically by the AN/ASG-21 fire control system.
Between 1972 and 1976, all surviving B-52Gs were provided with the AN/ASQ-151 Electro-optical Viewing System (EVS) to give the B-52 crew enhanced vision when flying at low level at night. The system was contained in two prominent fairings underneath the nose. The port fairing contained a steerable Westinghouse AN/AVQ-22 low-light-level television camera, whereas the starboard unit contained a Hughes AN/AAQ-6 forward-looking infrared (FLIR) sensor. Both units feed information into video display screens for the pilot, copilot, and both navigators. Data that could be presented on these screens included overlaid terrain avoidance profile trace in both TV or FLIR mode, alphanumeric symbology which included a height reading from the radar altimeter and time-to-go before weapons release, as well as indicated airspeed, heading error and bank steering, artificial horizon overlay and attitude and position of the sensor in use. When not in use, the EVS sensors rotated into the blisters for protection. The optical windscreens for the sensors even had inflight washing capability.
The Phase VI ECM Defensive Avionics Systems (ECP2519) was an upgrade program designed to improve the electronic countermeasures capabilities of the B-52G fleet. The program was started in December of 1971, but it took several years of development and testing before the final configuration was decided, and then several more years before the entire fleet could be upgraded. Upgrades were still continuing as recently as the late 1980s. Externally, the most visible change was in the extreme aft fuselage, which was extended farther to the rear by 40 inches to accommodate extra electronic equipment. However, the addition of so many antennae required that many other assorted bumps and warts be added over the exterior, which spoiled the fairly clean lines of the original B-52G. The equipment added as part of Phase VI consisted of an AN/ALR-20A countermeasures receiver, an AN/ALQ-117 active countermeasures set, an AN/ALR-46(V) digital radar warning receiver set, an AN/ALQ-122 false target generator system (sometimes known as Smart Noise Operation Equipment), AN/ALT-28 noise jammers, AN/ALQ-153 tail warning radar set, AN/ALT-32H and AN/ALT-32L high and low-band jamming sets, AN/ALT-16A barrage-jamming system, 12 AN/ALE-20 flare dispensers (192 flares) and eight AN/ALE-24 chaff dispensers (1125 bundles). The chaff dispensers were housed in the wing trailing edge, just outboard of the inner engine pod in the region between the two sets of flaps. This space had been occupied by an aileron on previous versions of the B-52. The AN/ALQ-117 system was supported by a pair of antennae which were housed inside a rather prominent teardrop-shaped bulge that protruded from each side of the nose underneath the cockpit, as well as special antennae installed in the extreme rear of the fuselage. The antenna for the ALT-28 was housed inside a rather prominent bump installed on the forward nose just ahead of the windshield. The antennae for the AN/ALQ-153 tail-warning radar were installed in a pod which was attached to the tip of the port horizontal tail. Subsequent refinements involved replacement of the AN/ALQ-117 unit by an AN/ALQ-172(V)1 unit, but still keeping the antennae associated with the original AN/ALQ-117.
By the mid-1970s, the AN/ASQ-38 bomb/navigation equipment initially fitted to the B-52G was becoming increasingly obsolete and subject to frequent malfunctions. Beginning in 1980, this system was replaced by the AN/ASQ-176 Offensive Avionics System (OAS). Almost all of the analog systems of the AN/ASQ-38 were replaced by solid-state digital electronic systems. The AN/ASQ-176 OAS had a MilStd 1553A digital data bus, and the package had new controls and displays as well as a new AN/APN-224 radar altimeter, two AN/ASN-136 inertial navigation systems, an AN/ASN-134 attitude heading reference system, an AN/APN-218 Doppler radar, an inertial navigation system plus missile interface units and major modifications to the primary attack radar. The system was specially configured for low-altitude use and embodied hardening against electromagnetic pulse effects. It was considerably more reliable than the AN/ASQ-38 that it replaced.
In the early 1980s, 98 B-52Gs were modified to carry the Boeing AGM-86B Air-Launched Cruise Missile (ALCM). The ALCM is powered by a 600 lb.s.t. Williams F107-WR-100 turbofan, which is fed by an inlet which folds out on the top of the missile. It is 20 feet 9 inches long. The ALCM is carried with the engine air intake, the wings, the elevons and the vertical tail surfaces all folded up into the body of the missile. When released from the B-52G, these surfaces deploy and the engine starts. When fully extended, the wings have a span of 12 feet and are swept at 25 degrees. Of the three tail surfaces, only the two horizontal surface provide control during flight. The ALCM is equipped with a single W80-1 nuclear warhead with a selectable yield in the 150-170 kiloton range. Guidance is by a combination of inertial guidance and terrain contour matching. Once the B-52G is airborne, the aircraft's INS and altimeter systems continuously provide precise positional data to the missile's INS. Prior to launch, the missile computer onboard the B-52G downloads target location along with a set of a set of pre-gathered mapping data into the onboard memory of the missile. The AGM-86B missile thus has a precise position plot at the time of launch, and uses terrain contour matching and a radar altimeter to survey the surrounding terrain as the missile flys over it at low level, comparing selected points along the way with those on the electronic map stored in the onboard computer. The missile can can fly at very low levels and can skim over mountains or down valleys in order to avoid detection. Maximum range of the AGM-86B is about 1500 miles and gross weight is 3200 pounds. The B-52G could carry six AGM-86Bs on each of the two underwing pylons.
Development of the AGM-86 cruise missile began back in the late 1960s, with the first flight taking place in 1976. The original AGM-86A version of the ALCM had been developed for the Rockwell B-1A Rockwell B-1A bomber, and the length of the missile had been constrained by the requirement that it be albe to fit inside the B-1A's weapons bay. When the B-1A was cancelled, the ALCM design was reworked for the B-52G, resulting in the AGM-86B version with a longer fuselage. The first AGM-86B became operational in 1982, and production ended in October of 1986. A total of 1715 ALCMs were built.
Under the provisions of the SALT II treaty, aircraft carrying cruise missiles must be readily identifiable as such by reconnaissance satellites, so the AGM-86B-equipped B-52G was provided with non-functional wing root fairings known as "strakelets". The modification had to be visible from above so that spy satellites could confirm the number of cruise missile-capable aircraft, and it had to be made aerodynamically and structurally integral with the aircraft so that the change could not be quickly altered or moved from one aircraft to another.
The AGM-86C is a modified version of the AGM-86B with a 992-pound high-explosive blast-fragmentation warhead in place of the nuclear warhead and a GPS navigation system replacing the terrain-following inertial navigation system. Since the high-explosive warhead is heavier than the nuclear warhead it replaced, the maximum range of the C-version is only 1200 miles. The AGM-86C entered service with the B-52G fleet in the late 1980s, but its existence was kept secret until 1992, when it was revealed that 35 of these weapons had been used against targets in Iraq during the Gulf War. Its classified codename was Senior Surprise. Most of the AGM-86Cs were expended during the Gulf War, but more were modified later. Since the end of the Cold War has all but eliminated the need for the nuclear mission, the Air Force has proposed that 200 or 300 more AGM-86Bs be converted to AGM-86C configuration.
Some sources indicate that there exist other modified versions of the AGM-86B that are equipped as decoys or fitted with carbon-fiber dispensers (like those use by the BGM-109s during the Gulf War) or which are capable of carrying electro-magnetic pulse (EMP) warheads which would generate a burst of microwave energy to disable enemy electronic communications systems.
By the end of 1988, 30 years of attrition had reduced the original fleet of 193 B-52Gs to 166. 98 of them had been converted to operate the AGM-86B ALCM. Units operating the ALCM included the 97th BW, the 379th BW, and the 416th BW, plus the 2nd BW's 596th BS. Some ALCM-configured B-52Gs were used for crew training tasks by the 93rd BW.
Non-ALCM B-52Gs featured a much shorter "stub" underwing pylon. This pylon was compatible with the original I-beam arrangement as well as with the newer Heavy Stores Adapter Beam (HSAB). When used in concert with the I-beam, external payload capacity was identical to that of aircraft retaining the AGM-28 pylon. When employed with the HSAB, however, only nine M117 bombs (or similar weapons) could be carried on each pylon. However, the HSAB permitted much heavier ordnance items to be carried externally such as five 2000-lb Mk84 bombs or Mk60 mines; six Mk55 or Mk56 mines, or six AGM-84 Harpoon antiship missiles. Alternatively, they can carry up to four AGM-142A Raptor 3000-lb stand-off attack missiles.
The B-52G could carry the AGM-84 Harpoon only externally, and could carry up to 12 of these missiles on the underwing pylons. The Harpoon is powered by a 600 lb.s.t. turbojet and has a warhead weighing 488 pounds. A special panel, known as a Harpoon Aircraft Command Launch Control Set or HACLCS, was fitted at the navigator's station. When the Harpoon's engine is started, the missile is still attached to the aircraft. Some 30 B-52Gs were assigned a maritime role, being fitted with a maximum load of 12 McDonnell Douglas AGM-84A/D Harpoon anti-ship missiles, six on each underwing pylon. Alternatively, conventional maritime mines could be carried on the wing pylon. The 441st BS of the 320th BW stationed at Mather AFB, California acted as the test and evaluation wing for the Harpoon. Harpoon-equipped aircraft were provided to the 69th BMS of the 42nd BMW at Loring AFB in Maine in 1984, followed by Andersen AFB in Guam. Following closure of these bases, B-52G operations moved to K. I. Sawyer AFB in Michigan. After that base was closed as well and the B-52Gs were earmarked for retirement, the Harpooon was fitted to 19 B-52Hs. The AGM-142A Raptor is a joint effort on the part of Israel's Rafael and the US's Lockheed Martin. It is a derivative of the Rafael Popeye missile that has been in service in Israel. The US version was developed under a program code-named Have Nap. It is a precision-guided air-to-ground missile that is designed to be effective against high-value ground and sea targets such as powerplants, missile sites, bridges, ships, and bunkers. The Raptor employs mid-course autonomous guidance based on inertial navigation, then homes in on its target using TV or imaging infrared terminal guidance, depending on what kind of sensor is installed. The radar navigator aboard the B-52G used a joystick to "ride" the missile in to its target while looking at the IR or TV display. The missile is 15.83 feet long and has an overall weight of about 3000 pounds. It carries a warhead of about 1000 pounds in weight, and can have blast fragmentation or penetrator warheads. There are four variants, depending on the warhead/ guidance system mix--AGM-142A (blast fragmentation/TV), AGM-142B (blast fragmentation/IIR), AGM-142C (penetrator/TV), AGM-142D (penetrator/IIR). The Raptor has been in production since 1989. The B-52G could carry four AGM-142 Raptors on each of its underwing pylons (or three plus a datalink pod).
Serials of B-52G:
57-6468/6475 Boeing B-52G-75-BW Stratofortress c/n 464173/464180 57-6476/6485 Boeing B-52G-80-BW Stratofortress c/n 464181/464190 57-6486/6499 Boeing B-52G-85-BW Stratofortress c/n 464191/464204 57-6500/6520 Boeing B-52G-90-BW Stratofortress c/n 464205/464225 58-158/187 Boeing B-52G-95-BW Stratofortress c/n 464226/464255 58-188/211 Boeing B-52G-100-BW Stratofortress c/n 4642256/464279 58-212/232 Boeing B-52G-105-BW Stratofortress c/n 464280/464300 58-233/246 Boeing B-52G-110-BW Stratofortress c/n 464301/464314 58-247/258 Boeing B-52G-115-BW Stratofortress c/n 464315/464326 59-2564/2575 Boeing B-52G-120-BW Stratofortress c/n 464327/464338 59-2576/2587 Boeing B-52G-125-BW Stratofortress c/n 464339/464350 59-2588/2602 Boeing B-52G-130-BW Stratofortress c/n 464351/464365 60-063/070 cancelled contract for Boeing B-52GSpecification of Boeing B-52G Stratofortress:
Engines: Eight Pratt & Whitney J57-P-43WB turbojets, each rated at 13,750 lb.s.t with water injection. Performance: Maximum speed 636 mph at 20,800 feet, 570 mph at 46,000 feet. Cruising speed 523 mph. Stalling speed 169 mph. Initial climb rate 5450 feet per minute. An altitude of 33,400 feet could br reached in 19 minutes. Cruising speed 523 mph. Service ceiling at combat weight 47,000 feet. Combat radius 4100 miles with 10,000 pound bombload. Ferry range 7976 miles. Takeoff ground run 8150 feet. Takeoff over 50-foot obstacle 10,400 feet. Dimensions: Length 157 feet 7 inches (later increased to 160 feet 10.9 inches), wingspan 185 feet 0 inches, height 40 feet 8 inches, wing area 4000 square feet. Weights: 168,445 pounds empty, 302,634 pounds combat, 488,000 pounds maximum takeoff. Armament: Four 0.50-inch M3 machine guns with 600 rpg in tail turret. Maximum offensive payload 50,000 pounds. Up to 20 Boeing AGM-86 ALCMs could be carried, eight internally and three on each underwing pylon. Internally, a clip of four B83 free-fall nuclear weapons could be carried. In the conventional role, could be configured with the Heavy Stores Adaptor Beam on the wing hardpoints so that nine 2000-lb Mk 84 bombs could be carried under each wing, with a further 27 internally. Alternatively, 27 750-lb M117 or 1000-lb Mk 83 bombs could be carried internally, with a further 24 on underwing positions fitted with the redundant Hound Dog pylon and multiple ejector racks. AGM-86C and the AGM-142 Have Nap EO guided missile can be carried on the HSABs.
Sources:
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
Post World War II Bombers, Marcelle Size Knaack, Office of Air Force History, 1988.
Boeing Aircraft Since 1916, Peter M. Bowers, Naval Institute Press, 1989.
United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Boeing B-52--A Documentary History, Walter Boyne, Smithsonian Institution Press, 1981.
Boeing's Cold War Warrior--B-52 Stratofortress, Robert F. Dorr and Lindsay Peacock, Osprey Aerospace, 1995.
Only the Best Come North, Rene J. Francillon, Air Fan International, Vol 1, No. 4, May 1996.
Encyclopedia of World Military Aircraft, Volume 1, David Donald and Jon Lake, AirTime, 1994.
Air-to Surface Weapon Directory, Doug Richardson and Piotr Butowski, Air International, May 1996.
Boeing B-52H, Robert F. Dorr and Brian C. Rogers, World Air Power Journal, Vol 27, Winter 1996.
e-mail from John Clearwater
e-mail from Stuart Erickson
|
The B-52G |
By Joe Baugher
The first Hound Dog-equipped B-52G unit was the 4135th Strategic Wing, based at Eglin AFB in Florida. This unit first deployed in December of 1959. At the peak in 1963, the Hound Dog force numbered 600. However, the weapon was not all that accurate, and its primary mission in the case of a nuclear war would probably have been to go ahead of the penetrating bombers to clear a path through enemy defenses. The Hound Dog rapidly became obsolete in the face of technological advances, the weapon being gradually withdrawn from service beginning in 1967. By the end of 1969, the number of missiles was down to 350. By the end of June 1975, the missile was finally taken off alert duty, but it remained on non-operational status for a while longer. The last AGM-28 was scrapped in June 1978, and the only ones left are now on display in museums.
During April of 1972, a contingent of B-52Gs were sent to Southeast Asia to support the bombing campaign against North Vietnam. It turned out that the B-52G was not nearly as suitable for conventional warfare as was the the 'D, since the 'G was unable to carry bombs externally and it did not have the Big Belly modifications that gave the B-52D such a fearsome conventional capability. A total of 28 B-52Gs were sent to Guam in April, followed by another 70 in late May and early June. The B-52G fleet deployed to the Pacific came under the control of the 72nd Strategic Wing (Prov). A number of Guam-based B-52Gs were fitted with AN/ALQ-119(V) ECM pods in place of the AN/ALE-25.
The B-52Gs participated in the Linebacker I and Linebacker II raids of 1972-73 at the end of the Vietnam war. The onboard ECM gear that had been fitted to the B-52G did afford some protection against enemy SAMs, but it was far from infallible, and the B-52G proved alarmingly vulnerable. Six B-52Gs were shot down by SAMS during Linebacker II. Only half of the B-52Gs on Guam had received the updates to their ECM equipment, leaving the rest with obsolete equipment which increased their vulnerability still further. The lighter structure of the B-52G which gave it such outstanding long-range performance had the undesired side-effect of making the aircraft more vulnerable to battle damage. Only one B-52G was able to survive the experience of being hit and damaged by a SAM, whereas several B-52Ds hit by SAMs were able to land safely. The B-52D actually had a better electronic countermeasures capability than the B-52G, and the tail gunner in the rear of the `D actually turned out to be quite useful in monitoring SAM launches. In the latter stages of Linebacker II, some of the B-52Gs were actually diverted in-flight to targets deemed to be less dangerous.
By the end of 1988, 30 years of attrition had reduced the original fleet of 193 B-52Gs to 166. 98 of them had been converted to operate the AGM-86B ALCM. Units operating the ALCM included the 97th BW, the 379th BW, and the 416th BW, plus the 2nd BW's 596th BS. Some ALCM-configured B-52Gs were used for crew training tasks by the 93rd BW.
Retirement of the B-52G began in the late 1980s. Mather's 320th BW was the first B-52G unit to be deactivated and ceased operations in July 1989. That same year, retired B-52Gs began to arrive at Davis-Monthan AFB for storage, but only 5 had arrived by the end of 1989. The 43rd SW at Andersen AFB, Guam was inactivated on June of 1990.
The Gulf War of 1990-1991 resulted in a temporary delay in the inactivation of B-52G units. On February 16, 1991, seven B-52Gs armed with 39 AGM-86C conventionally-armed cruise missiles took off from Barksdale AFB bound for Iraq. After a couple of refuellings, they arrived over the southern border of Iraq, where they launched 35 of their ALCMs against targets in central and southern Iraq. The targets included a power station, a telephone exchange, and other electrical generating facilities. The missiles were timed so that they would all reach their separate targets nearly simultaneously. All but two of the missiles seem to have struck their targets. The B-52Gs then returned to Barksdale via another set of refuelling operations. By the time that the mission was finally over, the crews had been in the air for 35 hours. It had been the longest-ranging combat mission in the history of aerial warfare.
Most of the B-52G missions against Iraqi targets were staged out of the base at Diego Garcia in the Indian Ocean. The participating groups were organized as the 4300 BW(P), a temporary unit set up at Diego Garcia for B-52Gs detached from the continental USA during this period. The 4300 BW was made up of elements of the 62nd BW from Carswell AFB plus the 69th BMS from Loring AFB, plus a handful of crews from Griffiss AFB and Castle AFB. On the 16th of January, 15 crews launched out of Diego Garcia to carry out area denial attacks on 5 airfields in southern Iraq. The attacks were made at low altitude (500 feet or lower). Most of these B-52G missions against Iraqi targets involved the delivery of conventional "iron" bombs.
In addition, there were B-52 missions against Iraq staged out of Prince Abdullah AB in Jeddah, Saudi Arabia. These planes were part of the 1708th BW (P), a temporary wing formed from B-52s out of Barksdale, Castle, Wurtsmith, and others. The planes arrived at dawn on the first day of the air war. One plane flew 29 missions out of Jeddah, the most of any bomber crew in the theater.
During Desert Storm, the B-52Gs completed approximately 1620 sorties. In fact, the B-52s managed to drop almost a third of the entire tonnage of bombs dropped by US aircraft. No B-52Gs were officially reported as having been lost as a result of enemy action during Desert Storm. However, several were damaged. One B-52G was damaged by a hit from an unknown type of missile, but was able to make it home safely. Another lost a couple of engines as a result of a near-miss by a SA-3 missile, whereas another was damaged by shrapnel from AAA fire. One B-52G (58-0248) was even damaged by a hit from an AGM-88A HARM missile fired by another US aircraft that was providing defense suppression support for the attacking force. The missile managed to home in on the tail-mounted gun-laying radar of the B-52G, and obliterated a sizeable chunk of the tail when it hit. Fortunately, the damaged B-52G was able to land safely at Jeddah and was sent to Guam for repair. One B-52G (59-2593) was lost on February 3, 1991. The cause of the loss was officially blamed on a catastrophic electrical system failure while returning to its base at Diego Garcia, but there are rumors going around that combat damage was actually responsible. Three of the crewmembers ejected safely before the aircraft crashed into the Indian Ocean, but three others ejected too late and were killed.
In spite of the Gulf War, the disposal of B-52Gs continued unabated. By the end of 1991, some 50 B-52Gs had arrived at Davis-Monthan for storage, and the number of active B-52Gs was now down to 90. In October 1991, the gunner was removed from the crew as an economy measure. The remainder were inactivated in 1992-93. By the end of 1993, there were only a couple of dozen B-52Gs still flying. The last B-52G went to storage at the Davis-Monthan AFB in the spring of 1994. A few were passed along to museum collections in the United States.
2 BW, Barksdale AFB, Louisiana
62 BS 1965-1992 - reassigned from 39 BW 6/25/65.
Inactivated 12/17/92
596 BS 1968-1992 - reassigned from 397 BW 4/16/68
5 BW, Travis AFB, California
23 BS 1959-1968
31 BS 1959-1960 - transferred to 4126 SW 1/60
17 BW, Beale AFB, California
34 BS 1975-1976 - took over assets of 744 BS/456 BW 9/30/75. Inactivated 9/30/76
19 BW, Robins AFB, Georiga
28 BS 1968-1983 - acquired assets of 781 BS/465 BW 7/25/68
28 BW, Ellsworth AFB, South Dakota
77 BS 1971-1977
39 BW, Eglin AFB, Florida
62 BS 1963-1965 - acquired assets of 301 BS/4135 SW 2/1/63; reassigned to 2 BW 6/25/65
42 BW, Loring AFB, Maine
69 BS 1959-1994. Inactivated 1994.
70 BS 1959-1966. Inactivated 6/25/66. Aircraft to 528 BS/380 SAW
43 SW, Andersen AFB, Guam.
60 BS 1983-1990. Inactivated 4/30/90
68 BW, Semour Johnson AFB, North Carolina
51 BS 1963-1982 - took over assets of 73 BS/4241 SW 4/15/63. Inactivated 9/30/82.
72 BW, Ramey AFB, Puerto Rico
60 BS 1959-1971. Inactivated 6/30/71, squadron transferred to 43 SW.
92 SAW, Fairchild AFB, Washington
325 BS 1970-1986
93 BW, Castle AFB, California
328 BS 1966-1967, 1974-1994. Inactivated 6/15/94
329 BS 1966-1967
97 BW, Blytheville AFB, Arkansas. Inactivated 4/1/92
340 BS 1960-1992.
319 BW, Grand Forks AFB, North Dakota
46 BS 1982-1987. Converted to B-1B 1987.
320 BW, Mather AFB, California. Inactivated 9/30/89
441 BS -1968-1989 - inactivated 9/30/89.
366 Wing, headquartered at Mountain Home AFB, Idaho but
stationed at Castle AFB, California.
34 BS 1992-1994 - disposed of B-52G in 1993/1994, transfered to Ellsworth AFB and equipped with B-1B as part of 366 Wing
379 BW, Wurtsmith AFB, Michigan
524 BS 1977-1992 - Inactivated 6/15/93
380 SAW, Plattsburgh AFB, New York
528 BS 1966-1971. Acquired aircraft from 70 BS/42 BW. Transitioned to FB-111A 1971.
397 BW, Dow AFB, Maine
596 BS 1963-1968 - acquired assets of 341 BS/4038 SW 2/1/63. Reassigned to 2 BW 4/68.
416 BW, Griffiss AFB, New York.
668 BS 1963-1992 - acquired assets of 75 BS/4039 SW 2/1/63
456 SAW/BW, Beale AFB, California
744 BS 1963-1975 - acquired assets of 31 BS/4126 SW 2/1/63. Inactivated 9/30/75, assets going to 34 BS/17 BW.
