Tag Archives: Strategic Bomber

17 June 1986

Boeing B-47E-25-DT Stratojet 52-166 is prepared to Depart NAWC China Lake. (U.S. Navy)
B-47E-25-DT Stratojet 52-166 is prepared to depart Armitage Field, NAWS China Lake, 17 June 1986. (U.S.  Air Force)

17 June 1986: After being returned to flyable condition, B-47E-25-DT Stratojet serial number 52-166, made the very last flight of a B-47 when it was flown by Major General John D. (“J.D.”) Moore and Lieutenant Colonel Dale E. Wolfe, U.S. Air Force, from the Naval Air Weapons Station China Lake in the high desert of Southern California, to Castle Air Force Base in California’s San Joaquin Valley, to be placed on static display.

52-166 had been built by the Douglas Aircraft Company at Air Force Plant No. 3, Tulsa, Oklahoma, in 1952. 52-166 had not been flown in twenty years, having sat in the Mojave Desert serving as a radar target. General Moore and Colonel Wolf were experienced B-47 pilots, though they hadn’t flown one in the same twenty years. Because the B-47 it had not been through a complete overhaul prior to the ferry flight, it was decided to leave the landing gear extended to avoid any potential problems.

During the 43 minute trip, the aircraft had several systems fail, including airspeed sensors, intercom, and partial aileron control. On approach to Castle Air Force Base, a 16 foot (4.9 meters) braking parachute was deployed. This created enough aerodynamic drag to slow the airplane while the early turbojet engines were kept operating at high power settings. These engines took a long time to accelerate from idle, making a go-around a very tricky maneuver. With the braking chute, though, releasing the chute allowed the airplane to climb out as the engines were already operating at high r.p.m.

B-47E-25-DT Stratojet 52-166 enroute Castle Air Force Base with a Lockheed T-33A Shooting Star chase. California’s Sierra Nevada Mountains are in the distance. (TSGT Michael Hagerty/U.S. Air Force)
Douglas-built B-47E-25-DT Stratojet 52-166 enroute Castle Air Force Base with a Lockheed T-33A Shooting Star chase, 17 June 1986. California’s Sierra Nevada Mountains are in the distance. (U.S. Air Force)

Designed by Boeing, the Stratojet was a high-subsonic speed strategic bomber and reconnaissance aircraft, in service from 1951 until 1977. The B-47 could fly higher and faster than jet fighters of the time, and it was also highly maneuverable. B-47E (Boeing Model 450-157-35) was flown by a two pilots in a tandem cockpit. A navigator/bombardier was at a station in the nose.

The B-47E Stratojet differed from the earlier B-47B primarily with upgraded engines and strengthened landing gear to handle an increase in maximum weight. The B-47E Stratojet is 107.1 feet (32.644 meters) long with a wingspan of 116.0 feet (35.357 meters), and an overall height of  28.0 feet (8.534 meters). The wings are shoulder-mounted and have a total area of 1,428 square feet (132.67 square meters). The wings’ leading edges are swept aft to 36° 37′. The angle of incidence is 2° 45′ and there is 0° dihdreal (the wings ware very flexible). The B-47E in standard configuration had an empty weight of 78,620 pounds (35,661 kilograms) and maximum takeoff weight of 200,000 pounds (90,718 kilograms).

The B-47E was powered by six General Electric J47-GE-25 turbojet engines in four nacelles mounted on pylons below the wings. This engine has a 12-stage axial-flow compressor, eight combustion chambers, and single-stage turbine. The -25 has a continuous power rating of 5,320 pounds of thrust (23.665 kilonewtons) at 7,630 r.p.m., at Sea Level; Military Power, 5,670 pounds (25.221 kilonewtons) at 7,800 r.p.m. (30 minute limit); and Maximum Power, 7,200 pounds (32.027 kilonewtons) at 7,950 r.p.m. with water/alcohol injection (5 minute limit). The J47-GE-25 has a maximum diameter of 3 feet, 1 inch (0.940 meters) and length of 12 feet, 0 inches (3.658 meters) and weighs 2,653 pounds (1,203 kilograms)

The B-47E had a maximum speed of 497 knots (572 miles per hour/920 kilometers per hour) at 20,000 feet (6,096 meters), and 485 knots (558 miles per hour/898 kilometers per hour) at 38,600 feet (11,765 meters).

The service ceiling was 31,500 feet (9,601 meters) and combat ceiling 40,800 feet (12,436 meters).

The combat radius of the B-47E was 1,780 nautical miles 2,048 miles (3,297 kilometers with a 10,000 pound (4,536 kilograms) bomb load. Ferry range with 14,720 gallons (55,721 liters) of fuel was 4,095 nautical miles (4,712 miles/7,584 kilometers).

For defense the B-47E was armed with two M24A1 20 mm autocannons with 350 rounds of ammunition per gun. The remotely-operated tail turret was controlled by the co-pilot.

The maximum bomb load of the B-47E was 12,000 pounds (5,443 kilograms). The B-47 could carry up to six 2,000 pound (907 kilogram) bombs, or one 10,670 pound (4,840 kilograms) “Special Store”: a B-41 three-stage radiation-implosion thermonuclear bomb with a yield of 25 megatons).

B-47E-25-DT Stratojet 52-166 flies over California's Central Valley farmland as it heads to Castle Air Force Base on the very last B-47 flight, 17 June 1986. (U.S. Air Force)
B-47E-25-DT Stratojet 52-166 flies over California’s Central Valley farmland as it heads to Castle Air Force Base on the very last B-47 flight, 17 June 1986. (U.S. Air Force)

A total of 2,032 B-47s were built by a consortium of aircraft manufacturers: Boeing Airplane Company, Wichita, Kansas; Douglas Aircraft Company, Tulsa, Oklahoma; Lockheed Aircraft Company, Marietta, Georgia.

The Stratojet is one of the most influential aircraft designs of all time and its legacy can be seen in almost every jet airliner built since the 1950s: the swept wing with engines suspended below and ahead on pylons. The B-47 served the United States Air Force from 1951 to 1977. From the first flight of the Boeing XB-47 Stratojet prototype, 17 December 1947, to the final flight of B-47E 52-166, was 38 years, 6 months, 1 day.

B-47E-25-DT Stratojet 52-166 on final approach to land at Castle Air Force Base, 17 June 1986. The braking chute is deployed. This is teh very last time that a B-47 flew.
Douglas-built B-47E-25-DT Stratojet 52-166 on final approach to land at Castle Air Force Base, 17 June 1986. The braking chute is deployed. This was the very last time that a B-47 flew.

© 2018, Bryan R. Swopes

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11 May 1964

XB-70A-1-NA 62-0001 rollout at Air Force Plant 42, 11 May 1964. (North American Aviation, Inc.)

11 May 1964: At Air Force Plant 42 near Palmdale, a small city in the high desert of southern California, the first prototype North American Aviation XB-70A-1-NA Valkyrie, 62-0001, was rolled out. More than 5,000 people were there to watch.

In August 1960, the U.S. Air Force had contracted for one XB-70 prototype and 11 pre-production YB-70 development aircraft. By 1964, however, the program had been scaled back to two XB-70As and one XB-70B. Only two were actually completed.

"Ride of the Valkyrs" by John Charles Dollman, 1909.
“Ride of the Valkyrs” by John Charles Dollman, 1909. In Norse mythology, the valkyries were immortal female figures who chose who among those who had died in battle were worthy of being taken to Valhalla.

The B-70 was designed as a Mach 3+ strategic bomber capable of flying higher than 70,000 feet (21,336 meters). Like its contemporaries, the Lockheed Blackbirds, the Valkerie was so advanced that it was beyond the state of the art. New materials and processes had to be developed, and new industrial machinery designed and built.

The XB-70A is a very large aircraft with a canard-delta configuration, built primarily of stainless steel and titanium. It has twin vertical fins combining the functions of stabilizers and rudders. The XB-70A Valkyrie prototype is 193 feet, 5 inches (58.953 meters) long, including the pitot boom, with a wingspan of 105 feet, 0 inches (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). The canard span is 28 feet, 10 inches (8.788 meters). The canard has flaps, while the delta wing used multiple separate elevons for pitch and roll control.

North American Aviation XB-70A-1-NA Valkyrie takes off at Edwards Air Force Base, 17 August 1965. (NASA)

The delta wing has an angle of incidence of 0° and its leading edges are swept to 65.57°, with 0° sweep at the trailing edge. The wings have a maximum of -2.60° of twist. The wings of 62-001 have no dihedral, but the second B-70, 62-0207, had 5° dihedral. The total wing area is 6,297.8 square feet (585.1 square meters).

The canard also has 0° of incidence and dihedral. Its leading edge is swept aft 31.70°, while the trailing edge sweeps forward 14.91°. The canard has a total area of 415.59 square feet (38.61 square meters). The canard flaps can be lowered to 20°.

The vertical fins have a height of 15 feet (4.572 meters). The leading edges are swept 51.77° and the trailing edges, 10.89°.

The B-70 was designed to “surf” on its own supersonic shock wave (this was called “compression lift”). The outer 20 feet (6.096 meters) of each wing could be lowered to a 25° or 65° angle for high speed flight. Although this did provide additional directional stability, it actually helped increase the compression lift, which supported up to 35% of the airplane’s weight in flight.

North American Aviation XB-70A-1-NA Valkyrie 62-0001. (U.S. Air Force)

The first prototype, 62-001, had an empty weight of 231,215 pounds (104,877 kilograms), an its maximum takeoff weight was 521,056 pounds (236,347 kilograms).

The XB-70A is powered by six General Electric YJ93-GE-3 engines, grouped together in the tail. These are single-spool, axial-flow, afterburning turbojet engines, which have an 11-stage compressor section and 2-stage turbine. The YJ93-GE-3 has a normal power rating of 17,700 pounds of thrust (78.734 kilonewtons); military power, 19,900 pounds (88.520 kilonewtons); and maximum power, 28,000 pounds (124.550 kilonewtons). All ratings are at 6,825 r.p.m. and are continuous. A special high-temperature fuel, JP-6, is required. The engine is 19 feet, 8.3 inches (6.002 meters) long, 4 feet, 6.15 inches (1.375 meters) in diameter, and weighs 5,220 pounds (2,368 kilograms).

Test firing one the 62-001’s General Electric YJ93-GE-3 afterburning turbojet engines. (LIFE Magazine)

62-0001 had a cruise speed of 1,089 knots (1,253 miles per hour/2,016 kilometers per hour) at 35,000 feet (10,688 meters), and maximum speed of 1,721 knots (1,980 miles per hour/3,187 kilometers per hour) at 79,050 feet (24,094 meters)—Mach 2.97. During flight testing, the XB-70A reached a maximum of Mach 3.08 (1,777 knots) with a sustained altitude of 74,000 feet (22,555 meters).

Fuel was carried in 11 internal tanks in the wings and fuselage and the maximum capacity was 43,646 gallons (165,218 liters), giving the bomber a combat range of 3,786 nautical miles (4,357 statute miles/7,012 kilometers).

The B-70 was designed to carry two B-53 two-stage radiation-implosion thermonuclear bombs in its internal bomb bay. A maximum of fourteen smaller weapons could be carried.

XB-70A-1 62-0001 first flew 21 September 1964, and exceeded Mach 3 for the first time on its 17th flight, 14 October 1965. Its final flight was 4 February 1969.

The second prototype, XB-70A-2-NA 62-0207, was destroyed in a midair collision. The third Valkyrie, XB-70B-NA 62-0208, was cancelled before completion.

62-0001 is in the collection of the National Museum of the United States Air Force. It has made 83 flights with just 160 hours, 16 minutes, total flight time.

XB-70A-1-NA Valkyrie 62-0001 in cruise at very high altitude, 1968. (NASA)
XB-70A-1-NA Valkyrie 62-0001 in cruise at very high altitude, 1968. (NASA)

© 2019, Bryan R. Swopes

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30 April 1959

Convair B-36J-1-CF 52-2220 at NMUSAF, Wright-Patterson AFB, Ohio.

30 April 1959: Convair B-36J-1-CF Peacemaker, serial number 52-2220, landed at Wright-Patterson Air Force Base, Dayton, Ohio, completing the very last flight ever made by one of the giant Cold War-era bombers. It is on the collection of the National Museum of the United States Air Force.

Convair B-36J 52-2220 was among the last group of 33 B-36 bombers built. It was operated by an aircraft commander/pilot, co-pilot, two navigators, bombardier, two flight engineers, two radio operators, two electronic countermeasures operators and five gunners, a total 16 crewmembers. Frequently a third pilot and other additional personnel were carried.

Crewmebers pose in front of a B-36F, wearing capstan-type partial pressure suites for protection at high altitude. Front (L-R): G.L. Whiting, B.L. Woods, I.G. Hanten, and R.L. D’Abadie. Back (L-R):A.S. Witchell, J.D. McEachern, J.G. Parker and R. D. Norvell. (Jet Pilot Overseas)
Crew members pose in front of a Convair B-36F-1-CF Peacemaker, 49-2669, wearing David Clark Co. S-2 capstan-type partial pressure suits and early K-1 “split shell” 2-piece helmets for protection at high altitude. Front (L-R): G.L. Whiting, B.L. Woods, I.G. Hanten, and R.L. D’Abadie. Back (L-R):A.S. Witchell, J.D. McEachern, J.G. Parker and R. D. Norvell. (Jet Pilot Overseas)

The bomber is 162 feet, 1 inch (49.403 meters) long with a wingspan of 230 feet (70.104 meters) and overall height of 46 feet, 9 inches (14.249 meters). The empty weight is 171,035 pounds (77,580 kilograms) and combat weight is 266,100 pounds (120,700 kilograms). Maximum takeoff weight is 410,000 pounds (185,973 kilograms).

The B-36J has ten engines. There are six air-cooled, supercharged 4,362.49 cubic-inch-displacement (71.49 liter) Pratt & Whitney Wasp Major C6 (R-4360-53) four-row, 28-cylinder radial engines placed inside the wings in a pusher configuration. These had a compression ratio of 6.7:1 and required 115/145 aviation gasoline. The R-4360-53 had a Normal Power rating of 2,800 horsepower at 2,600 r.p.m. Its Military Power rating was 3,500 horsepower at 2,800 r.p.m., and 3,800 horsepower at 2,800 r.p.m. with water injection—the same for Takeoff. The engines turned three-bladed Curtiss Electric constant-speed, reversible propellers with a diameter of 19 feet, 0 inches (5.791 meters) through a 0.375:1 gear reduction. The R-4360-53 is 9 feet, 9.00 inches (2.972 meters) long, 4 feet, 7.00 inches (1.397 meters) in diameter, and weighs 4,040 pounds (1,832.5 kilograms).

Four General Electric J47-GE-19 turbojet engines are suspended under the wings in two-engine pods. The J47 is a  single-shaft axial-flow turbojet engine with a 12-stage compressor section, 8 combustion chambers, and single-stage turbine. The J47-GE-19 was modified to run on gasoline and was rated at 5,200 pounds of thrust (23.131 kilonewtons).

The B-36J had a cruise speed of 203 miles per hour (327 kilometers per hour) and a maximum speed of 411 miles per hour (661 kilometers per hour) at 36,400 feet (11,905 meters) . The service ceiling was 39,900 feet (12,162 meters) and its range was 6,800 miles (10,944 kilometers) with a 10,000 pound (4,536 kilogram) bomb load. The maximum range was 10,000 miles (16,093 kilometers).

Convair B-36J-1-CF Peacemaker 52-2220. (San Diego air and Space Museum Archives)

Designed during World War II, nuclear weapons were unknown to the Consolidated-Vultee engineers. The bomber was built to carry up to 86,000 pounds (39,009 kilograms) of conventional bombs in two bomb bays. It could carry the 43,600 pound (19,776.6 kilogram) T-12 Cloudmaker, a conventional explosive earth-penetrating bomb, or several Mk.15 thermonuclear bombs. By combining the bomb bays, one Mk.17 25-megaton thermonuclear bomb could be carried.

For defense, the B-36J had six retractable defensive gun turrets and gun turrets in the nose and tail. All 16 guns were remotely operated. Each position mounted two M24A1 20 mm autocannons. 9,200 rounds of ammunition were carried.

Between 1946 and 1954, 384 B-36 Peacemakers were built. They were never used in combat. Only five still exist.

Convair B-36J-1-CF 52-2220 being moved from Building 1 to Building 3 at the National Museum of the United States Air Force, October 2002. (U.S. Air Force)

© 2017, Bryan R. Swopes

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15 April 1952

The Boeing YB-52 Stratofortress, 49-231, takes off from Boeing Field at 11:09 a.m., 15 April 1952. (Robert F. Dorr Collection)
The Boeing YB-52 Stratofortress, 49-231, takes off from Boeing Field at 11:09 a.m., 15 April 1952. (Robert F. Dorr Collection)

15 April 1952: At 11:09 a.m., Boeing’s Chief of Flight Test, Alvin M. “Tex” Johnston, and Lieutenant Colonel Guy M. Townsend, U.S. Air Force, ran all eight turbojet engines to full power and released the brakes on the YB-52 Stratofortress prototype, 49-231.

With an awesome eight-engine roar, the YB-52 sprang forward, accelerating rapidly, wings curving upward as they accepted the 235,000-pound initial flight gross weight. At V2 (takeoff speed) the airplane lifted off the runway, because of the 6-degree angle of incidence of the wing, and at 11:08 a.m. we were airborne. The initial flight of the YB-52 had begun.

Tex Johnston: Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1992, Chapter 13 at Pages 397–398.

Alvin M. "Tex" Johnston, test pilot, after the first flight of the Boeing XB-52 Stratofortress prototype, 2 October 1952. (LIFE via Jet Pilot Overseas)
Alvin M. “Tex” Johnston, Boeing Chief of Flight Test, after the first flight of the Boeing XB-52 Stratofortress prototype, 2 October 1952. (LIFE via Jet Pilot Overseas)

The YB-52 remained over the Seattle area for approximately 40 minutes while Johnson and Townsend ran through a series of systems checks. When completed, they climbed to 25,000 feet (7,620 meters) and flew the new bomber to Larson Air Force Base at Moses Lake, Washington, where they stayed airborne for continued testing. The Stratofortress finally touched down after 3 hours, 8 minutes—the longest first flight in Boeing’s history up to that time. Johnston radioed that the airplane performed exactly as the engineers had predicted.

Boeing YB-52 Stratofortress 49-231. (Boeing)

The YB-52 had actually been ordered as the second of two XB-52s, but modifications and additional equipment installed during building resulted in enough differences to warrant a designation change. The first XB-52, 49-230, should have been the first to fly, but it was damaged during ground testing.

Boeing XB-52 Stratofortress 49-230. (U. S. Air Force)

The Boeing XB-52 and YB-52 were prototypes for a very long range strategic bomber. Both were built with a tandem cockpit for the pilot and co-pilot, similar to the earlier B-47 Stratojet. The wings were swept and mounted high on the fuselage (“shoulder-mounted”). The eight turbojet engines were in in two-engine nacelles mounted on pylons, below and forward of the wings. This had the effect of preventing the airplane’s center of gravity from being too far aft, and also provided cleaner air flow across the wings. The B-52’s landing gear has four main struts with two wheels, each. They can turn to allow the airplane to face directly into the wind while the landing gear remain aligned with the runway for takeoff and landing. With the landing gear under the fuselage, the wings could be constructed with greater flexibility.

Boeing YB-52 Stratofortress 49-231. (U.S. Air Force)
Boeing YB-52 Stratofortress 49-231. (U.S. Air Force)

The YB-52 was 152 feet, 8 inches (46.533 meters) long with a wingspan of 185 feet, 0 inches (56.388 meters). The prototype’s overall height was 48 feet, 3.6 inches (14.722 meters). The vertical fin could be folded over to the right so that the B-52 could fit into a hangar. The total wing area was 4,000 square feet (371.6 square meters). The wings’ leading edges were swept aft to 36° 54′. Their angle of incidence was 6° and there was 2° 30′ dihedral. The YB-52 had an empty weight of 155,200 pounds (70,398 kilograms) and gross weight of 405,000 pounds (183,705 kilograms).

The YB-52 was powered by eight Pratt & Whitney Turbo Wasp YJ57-P-3 turbojet engines. The J57 was a two-spool, axial-flow turbojet developed from an experimental turboprop engine. It had 16-stage compressor section (9 low- and 7-high-pressure stages), 8 combustors and a 3-stage turbine section (1 high- and 2 low-pressure stages). The YJ57-P-3s had a continuous power rating of 8,700 pounds of thrust (38.70 kilonewtons). The YJ57-P-3 was 183.5 inches (4.661 meters) long, 41.0 inches (1.041 meters) in diameter and weighed 4,390 pounds (1,991 kilograms).

The YB-52 had a cruise speed of 519 miles per hour (835 kilometers per hour) and maximum speed of 611 miles per hour (983 kilometers per hour) at 20,000 feet (6,096 meters). Its range was 7,015 miles (11,290 kilometers).

The two prototypes were unarmed.

Boeing YB-52 Stratofortress 49-231

The B-52 was produced by Boeing at its plants in Seattle and Wichita from 1952 to 1962, with a total of 744 Stratofortresses built. The last version, the B-52H, entered service with the Strategic Air Command in 1960. The final B-52, B-52H-175-BW Stratofortress 61-0040, was rolled out at Wichita, Kansas, 26 October 1962. This airplane remains in service with the United States Air Force. The newest B-52 in service, 61-0040 is 56 years old and has flown more than 21,000 hours.

All previous versions, B-52A through B-52G, have long been retired to The Boneyard and scrapped. Of the 102 Boeing B-52H Stratofortress bombers, 76 are still in the active inventory. One, 61-007, known as Ghost Rider, was recently taken from Davis-Monthan and after an extensive restoration and update, returned to service.

The YB-52 prototype was retired to the National Museum of the United States Air Force in the late 1950s. By the mid-60s it was determined to be excess and was scrapped.

Captain William Magruder (standing) Boeing Chief Test Pilot Alvin M. Johnston (center) and Lieutenant Colonel Guy M. Townsend with the Boeing YB-52 Stratofortress 49-231. (Boeing)
Left to right: Captain William Magruder, USAF; Boeing Chief Test Pilot Alvin M. Johnston; and Lieutenant Colonel Guy M. Townsend, USAF, with the Boeing YB-52 Stratofortress, 49-231. (Boeing)

© 2019, Bryan R. Swopes

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6 March 1961

Boeing B-52H-135-BW Stratofortress 60-0006. (United States Air Force)

6 March 1961: The B-52H is the final version of the Boeing B-52 Stratofortress intercontinental strategic bomber. There are discrepancies as to the date of its first flight, with sources varying by as much as eight months. One very reliable source writes that the flight took place on 20 July 1960. A U.S. Air Force publication says that it was in March 1961, and another source (Boeing) says that it was 6 March 1961. (This third date is convenient, so, for no other reason, I’ve posted this article using that date.)

The U.S. Air Force contracted 62 B-52H Stratofortresses, serial numbers 60-0001 through 60-0062, on 6 May 1960. A second group of 40, serials 61-0001 through 61-0040, were ordered later. All were built at the Boeing Wichita plant.

A fourth source identifies the aircraft in the photograph above, Boeing B-52H-135-BW Stratofortress 60-0006, (Boeing serial number 464-371) as the first B-52H to fly. The existence of a nice aerial portrait suggests that this may be correct.

The B-52H, like the B-52G, is a re-engineered aircraft, structurally different from the XB-52, YB-52, and B-52A–B-52F Stratofortress variants. It is lighter, carries more internal fuel, giving it a longer unrefueled range, and is strengthened for low-altitude flight. The shorter vertical fin is intended to prevent the losses caused by the original tall fin in turbulent air. The B-52H is equipped with quieter, more efficient turbofan engines.

A Boeing B-52H Stratofortress carries four Douglas Skybolt ALBMs. (U.S. Air Force)
A Boeing B-52H Stratofortress carries four Douglas GAM-87 Skybolt ALBMs. (U.S. Air Force)

The B-52H was developed to carry four Douglas GAM-87 Skybolt air-launched ballistic missiles on pylons mounted under the wings, inboard of the engines. The Skybolt was armed with a 1-megaton W-59 thermonuclear warhead. The program was cancelled, however, and the North American Aviation AGM-28 Hound Dog air-launched cruise missile was used instead. (Interestingly, the Hound Dog’s Pratt & Whitney J52-P-3 turbojet engine could be used to supplement the B-52’s takeoff thrust, and then refueled from the bomber’s tanks before being air-launched.)

Boeing B-52G Stratofortress aremd with two North American Aviation AGM-28 Hound Dog ACLMs. (U.S. Air Force)
Boeing B-52G-105-BW Stratofortress 58-0216 armed with two North American Aviation AGM-28 Hound Dog ALCMs. (U.S. Air Force)

The B-52H is a sub-sonic, swept wing, long-range strategic bomber. It was originally operated by a crew of six: two pilots, a navigator and a radar navigator, an electronic warfare officer, and a gunner. (The gunner was eliminated after 1991). The airplane is 159 feet, 4 inches (48.565 meters) long, with a wing span of 185 feet (56.388 meters). It is 40 feet, 8 inches (12.395 meters) high to the top of the vertical fin. The B-52H uses the vertical fin developed for the B-52G, which is 22 feet, 11 inches (6.985 meters) tall. This is 7 feet, 8 inches (2.337 meters) shorter than the fin on the XB-52–B-52F aircraft, but the fin’s chord is longer. The bomber has an empty weight of 172,740 pounds (78,354 kilograms) and its Maximum Takeoff Weight (MTOW) is 488,000 pounds (221,353 kilograms).

The most significant difference between the B-52H and the earlier Stratofortresses is the replacement of the eight Pratt & Whitney J57-series turbojet engines with eight Pratt & Whitney Turbo Wasp JT3D-2 (TF33-P-3) turbofans, which are significantly more efficient. They are quieter and don’t emit the dark smoke trails of the turbojets. The TF-33 is a two-spool axial-flow turbofan engine with 2 fan stages, a 14-stage compressor section (7-stage intermediate pressure, 7-stage high-pressure) and and a 4-stage turbine (1-stage high-pressure, 3-stage low-pressure). Each engine produces a maximum of 17,000 pounds of thrust (75.620 kilonewtons). The TF33-P-3 is 11 feet, 10 inches (3.607 meters) long, 4 feet, 5.0 inches (1.346 meters) in diameter and weighs 3,900 pounds (1,769 kilograms).

The B-52H has a cruise speed of 525 miles per hour (845 kilometers per hour). It has a maximum speed of 632 miles per hour (1,017 kilometers per hour) at 23,800 feet (7,254 meters)—0.908 Mach. The service ceiling is 47,700 feet (14,539 meters). The unrefueled range is 8,000 miles (12,875 kilometers). With inflight refueling, its range is limited only by the endurance of its crew.

The B-52H was armed with a 20 mm M61 Vulcan 6-barreled cannon in place of the four .50-caliber machine guns of the earlier variants.
The B-52H was armed with a 20 mm M61A1 Vulcan 6-barreled rotary cannon in place of the four .50-caliber machine guns of the earlier variants. The gun was removed after 1991.

The B-52H was armed with a 20mm M61A1 Vulcan six-barreled rotary cannon in a remotely-operated tail turret. The gun had a rate of fire of 4,000 rounds per minute, and had a magazine capacity of 1,242 rounds. After 1991, the gun and its radar system were removed from the bomber fleet. The flight crew was reduced to five.

The B-52H can carry a wide variety of conventional free-fall or guided bombs, land-attack or anti-ship cruise missiles, and thermonuclear bombs or cruise missiles. These can be carried both in the internal bomb bay or on underwing pylons. The bomb load is approximately 70,000 pounds (31,751 kilograms).

A Boeing B-52H Stratofortress dropping forty-five M117 750-pound (340 kilogram) general purpose bombs. (Senior Airman Carlin Leslie, U.S. Air Force)

The first of 102 B-52H Stratofortresses entered service on 9 May 1961. The last one, 61-0040, was rolled out 26 October 1962. Beginning in 2009, eighteen B-52H bombers were placed in climate-controlled long term storage at Tinker Air Force Base, Oklahoma. As of December 2015, fifty-eight of the bombers remained in the active fleet of the United States Air Force and eighteen are assigned to the Air Force Reserve. In 2014, the entire fleet began a major avionics upgrade. The B-52H is expected to remain in service until 2040.

An ordnance crew loads a rotary launcher with 8 cruise missiles into teh bomb bay of a B-52H Stratofortress. (Senior Airman Amber Ashcraft/U.S. Air Force)
An ordnance crew loads a rotary launcher with 8 cruise missiles into the bomb bay of a B-52H Stratofortress. (Senior Airman Amber Ashcraft/U.S. Air Force)

60-0006, the first B-52H to fly, crashed while making a ground-controlled (GCA) approach to Wright Patterson Air Force Base, Dayton, Ohio, at 2:07 a.m., 30 May 1974. The bomber’s rudder and elevators failed. Although 60-0006 was destroyed, all seven airmen on board, Captains Charles Brown, Robert E. Smith, William G. Heckathorn, Paul C. Hoffman, 1st Lieutenants John D. Weaver, James R. Villines, and 2nd Lieutenant Robert E. Pace, survived the accident without serious injuries.

Wreck of Boeing B-52H-135-NW Stratofortress 60-0006 at Wright-Patterson AFB, 30 May 1974. (Dayton Daily News Archive)
Wreck of Boeing B-52H-135-BW Stratofortress 60-0006 at Wright-Patterson AFB, 30 May 1974. Two AGM-28 Hound Dog ACLMs are lying in the background. (Dayton Daily News Archive)
A Boeing B-52H Stratofortress during a deterrent patrol near the Democratic People’s Republic of North Korea, 2016. The bomber is carrying a load of Mk.84 2,000-pound JDAM “smart” bombs. (Master Sgt. Lance Cheung, U.S. Air Force)
Boeing B-52H-165-BW Stratofortress 61-0007 takes off at Tinker Air Force Base on a functional test flight, 30 August 2016. The airplane, named “Ghost Rider,” was overhauled after being stored for eight years at The Boneyard, Davis-Monthan Air Force Base, Arizona. 61-0007 is the very first B-52 to have been “regenerated.” (Kelly White/U.S. Air Force)

© 2017, Bryan R. Swopes

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