Tag Archives: Strategic Bomber

26 October 1962

The last of 744 Boeing B-52 Stratofortress bombers, B-52H-175-BW, 61-0040, is rolled out at the Boeing plant at Wichita, Kansas. (Boeing)
The last of 744 Boeing B-52 Stratofortress bombers, B-52H-175-BW, 61-0040, is rolled out at the Boeing plant at Wichita, Kansas. (Boeing)

26 October 1962: The very last Boeing B-52 Stratofortress was delivered to the United States Air Force. B-52H-175-BW 61-0040, which was rolled out at Wichita, Kansas, 22 June 1962, was the 744th B-52 built by Boeing at its Seattle and Wichita plants.

The B-52 Stratofortress is a long range strategic bomber powered by eight jet engines. The first flight took place 15 April 1952 at Boeing Field, Seattle, Washington, when test pilots Alvin M. (“Tex”) Johnston and Lieutenant Colonel Guy M. Townsend, U.S. Air Force, took off in the second prototype, the YB-52, serial number 49-231. The first production aircraft, B-52A-1-BO, 52-001, was rolled out at Boeing’s Plant 2 on 18 March 1954. The first operational Stratofortress, an RB-52B-15-BO, 52-8711, was delivered to the Strategic Air Command’s 93d Bombardment Wing (Heavy) at Castle Air Force Base, California, 29 June 1955. (52-8711 was retired 29 September 1965 and is on display at the Strategic Air and Space Museum, Offutt AFB, Nebraska.)

Boeing’s Seattle Plant 2 produced B-52 A, B, C model Stratofortresses, with D, E, and F versions built both there and at Wichita, Kansas. With the introduction of the B-52G, all bomber production was shifted to Wichita in 1957. The Wichita plant produced the B-52D through B-52H bombers from 1955 until production ended in 1962.

Boeing B-52H-175-BW Stratofortress 61-0040 in SIOP camouflage, assigned to 2nd Air Force, circa 1975. (U.S. Air Force)

The Stratofortress was designed as a strategic bomber armed with nuclear bombs. It was originally powered by turbojet engines, but more powerful and efficient turbofan engines were introduced with the final version, the B-52H.

B-52D and B-52F Stratofortresses were first used in combat during the Vietnam War when they carried as many as 108 500-pound bombs to attack industrial targets in North Vietnam and enemy troop concentrations. Thirty B-52s were lost due to enemy action during the war. Most of these bombers were lost to radar-guided surface to air missiles. Three B-52D crews are credited with air-to-air victories, when they each shot down a Mikoyan-Gurevich MiG 21 interceptor with their four tail-mounted .50-caliber Browning machine guns. (The B-52H was equipped with a 20mm M61 Vulcan rotary cannon, though this has been removed.)

The Stratofortress was used during Operation Desert Storm in 1991, Operation Allied Force in 1999, and Operation Enduring Freedom from 2001 to the present.

Boeing B-52H Stratofortress. (U.S. Air Force)

The B-52H is the only version still in service. 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. As of 19 May 2016, 75 of the original 102 bombers, including 61-0040, are still in the U.S. Air Force inventory. Beginning in 2013, the Air Force began a fleet-wide technological upgrade for the B-52H, including a digital avionics and communications system, as well as an internal weapons bay upgrade.

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.)

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)

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 wings of the B-52H have a total area of 4,000 square feet ( square meters). The leading edges are swept aft to 36° 58′. The angle of incidence is 6°, and there is 2° 30′ dihedral. (The wings are very flexible and exhibit pronounced anhedral when on the ground.) To limit twisting in flight, the B-52 has spoilers on top of the wings rather than ailerons at the trailing edges.

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). The TF33-P-3 has a maximum continuous power rating of 14,500 pounds of thrust (64.499 kilonewtons) at 9,750 r.p.m., N1. Military Power, limited to 30 minutes, is 16,500 pounds (73.396 kilonewtons) at 10,000 r.p.m., N1. Each engine produces a maximum of 17,000 pounds of thrust (75.620 kilonewtons) at 10,050 r.p.m., N1, with a 5-minute limit. The TF33-P-3 is 11 feet, 4.32 inches (3.4625 meters) long, 4 feet, 4.93 inches (1.3442 meters) in diameter and weighs 3,900 pounds (1,769 kilograms).

The B-52H has a cruise speed of 456 knots (525 miles per hour/845 kilometers per hour). It has a maximum speed, with Military Power, of 555 knots (639 miles per hour/1,028 kilometers per hour) at 20,700 feet (6,309 meters)—0.906 Mach. The service ceiling is 46,900 feet (14,295 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.

BARKSDALE AIR FORCE BASE, La. (AFPN) -- Munitions on display show the full capabilities of the B-52 Stratofortress. (U.S. Air Force photo by Tech. Sgt. Robert J. Horstman)
A Boeing B-52H Stratofortress with a display of potential weapons. (Technical Sergeant Robert J. Horstman, U.S. Air Force)

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 maximum bomb load is approximately 70,000 pounds (31,751 kilograms).

The B-52H was equipped with a General Electric M61 Vulcan 20 mm six-barreled rotary cannon (a “Gatling gun”) 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 very last B-52 Stratofortress built, B-52H-175-BW 61-0040, on takeoff at Minot Air Force Base. (U.S. Air Force)

Beginning in 2009, eighteen B-52H bombers were placed in climate-controlled long term storage at Tinker Air Force Base, Oklahoma.  In 2014, the entire fleet began a major avionics upgrade. 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.

Recently, a B-52H-156-BW Stratofortress, 61-0007, Ghost Rider, was returned to operational status after eight years in storage at Davis-Monthan Air Force Base, Tucson, Arizona. 45,000 man-hours were required to restore the bomber.

The B-52H is expected to remain in service until 2040.

61 years after roll-out, 61-0040 is still in service with the United States Air Force, assigned to the 23rd Bomb Squadron, 5th Bomb Wing at Minot Air Force Base, North Dakota.

Boeing B-52H-175-BW Stratofortress 61-0040 parked at Anderson Air Force Base, Guam. (U.S. Air Force)

© 2019, Bryan R. Swopes

16 October 1963

Convair B-58A-20-CF Hustler 61-2059, Greased Lightning. (U.S. Air Force)
Major Sidney Kubesch with his wife, Joanna Alice Cole Kubesch, 16 October 1963. (Kokomo Tribune)
Major Sidney J. Kubesch, U.S. Air Force, with his wife, Joanna Alice Cole Kubesch, at RAF Greenham Common, 16 October 1963. (Kokomo Tribune)

16 October 1963: Operation Greased Lightning. Major Sidney J. Kubesch, Major John Barrett and Captain Gerard Williamson flew from Tokyo, Japan, to London, England, non-stop, in 8 hours, 35 minutes, 20.4 seconds. Their airplane was a Convair B-58A-20-CF Hustler, serial number 61-2059, named Greased Lightning. It was assigned to the 305th Bombardment Wing, 19th Air Division, at Bunker Hill Air Force Base, Indiana.

Five inflight refuelings were required to complete the flight. The bomber had to slow from its supersonic cruise to rendezvous with the tankers. The B-58’s average speed was 692.71 miles per hour (1,114.81 kilometers per hour). The time from Tokyo to Anchorage, Alaska was 3 hours, 9 minutes, 42 seconds at an average speed of 1,093.4 miles per hour (1,759.7 kilometers per hour); and Anchorage to London, 5 hours, 24 minutes, 54 seconds at 826.9 miles per hour (1.330.8 kilometers per hour).

Greased Lightning‘s speed record still stands.

Screen Shot 2015-10-15 at 08.56.36 The three crewmen were awarded the Distinguished Flying Cross.

Major Sidney Kubesch, Aircraft Commander, John Barrett, Navigator and Gerard Williamson. (Kokomo Tribune)
Major Sidney J. Kubesch, Aircraft Commander, Major John Barrett, Navigator and Captain Gerard Williamson. (Kokomo Tribune)

The B-58 Hustler was a high-altitude Mach 2 strategic bomber which served with the United States Air Force from 1960 to 1970. It was crewed by a pilot, navigator/bombardier and a defensive systems operator located in individual cockpits. The aircraft is a delta-winged configuration similar to the Convair F-102A Delta Dagger and F-106 Delta Dart supersonic interceptors.

The Hustler is 96 feet, 10 inches (29.515 meters) long, with a wing span of 56 feet, 10 inches (17.323 meters) and an overall height of 31 feet 5 inches (9.576 meters). The wing’s leading edge is swept back at a 60° angle and the fuselage incorporates the “area rule” which resulted in a “wasp waist” or “Coke bottle” shape for a significant reduction in aerodynamic drag. The airplane’s only control surfaces are two “elevons” and a rudder, and there are no flaps.

The B-58A was powered by four General Electric J79-GE-5 axial-flow afterburning turbojet engines, suspended under the wings from pylons. This was a single-shaft engine with a 17-stage compressor and 3-stage turbine, rated at 10,300 pounds of thrust (45.82 kilonewtons), and 15,600 pounds (69.39 kilonewtons) with afterburner. The J79-GE-5 was 16 feet, 10.2 inches (5.136 meters) long and 3 feet, 2.0 inches (0.965 meters) in diameter.

The bomber had a cruise speed of 610 miles per hour (981.7 kilometers per hour) and a maximum speed of 1,325 miles per hour (2,132.4 kilometers per hour). The service ceiling is 64,800 feet (19,751 meters). Unrefueled range is 4,400 miles (7,081 kilometers). Maximum weight is 168,000 pounds (76,203.5 kilograms).

The B-58 weapons load was a combination of a W-39 warhead, and/or Mk.43 or B61 nuclear bombs. The W-39 warhead, the same used with the Redstone IRBM or Snark cruise missile, was carried in a jettisonable centerline pod, which also carried fuel for the aircraft. The smaller bombs were carried on underwing hardpoints. For defense, there was a General Electric M61 Vulcan 20×102 mm six-barreled rotary cannon mounted in the tail, with 1,200 rounds of linked ammunition, controlled by the Defensive Systems Officer.

Convair B-58A-20 CF 61-2059 is in the collection of the Strategic Air and Space Museum, Ashland, Nebraska.

Convair B-58A-20-CF 61-2059, “Greased Lightning,” at the Strategic Air and Space Museum, Ashland, Nebraska. (SASM)

© 2017, Bryan R. Swopes

2 October 1952

Boeing XB-52 Stratofortress 49-230 takes off for the first time, at Boeing Field, Seattle, Washington, 2 October 1952. (LIFE Magazine via Jet Pilot Overseas)

2 October 1952: The Boeing XB-52 Stratofortress prototype, 49-230, made its first flight at Boeing Field, Seattle, Washington, with test pilot Alvin M. “Tex” Johnston in command.  Lieutenant Colonel Guy M. Townsend, U.S. Air Force, acted as co-pilot.

The first of two prototype long-range, high-altitude, heavy bombers, the XB-52 had been damaged during ground testing and extensive repairs were required, which delayed its initial flight. The second prototype, YB-52 49-231, made the type’s first flight nearly six months earlier, on 15 April 1952.

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

The prototype Stratofortress the largest jet aircraft built up to that time. It was 152.7 feet (46.543 meters) long with a wingspan of 185.0 feet, (56.388 meters) and 48.25 feet (14.707 meters) to the top of the vertical fin. The leading edges of the wings were swept back 36° 54′.  The XB-52 had an empty weight of 155,200 pounds (70,398 kilograms) and its maximum takeoff weight was 390,000 pounds (176,901 kilograms). Fuel capacity was 27,417 gallons (103,785 liters).

Lieutenant Colonel Guy M. Townsend, U.S. Air Force. (Jet Pilot Overseas)
Lieutenant Colonel Guy M. Townsend, U.S. Air Force. (Jet Pilot Overseas)

The XB-52 was powered by eight Pratt & Whitney YJ57-P-3 turbojet engines, with a normal power rating of 8,700 pounds static thrust at Sea Level (38.700 kilonewtons). The prototype bomber had  a cruising speed of 519 miles per hour (835 kilometers per hour), and a maximum speed of 611 miles per hour (983 kilometers per hour) at 20,000 feet (6,048 meters). The planned bombing altitude was 46,500 feet (14,173 meters) and it had a service ceiling of 52,300 feet (15,941 meters). The XB-52 had an initial rate of climb of 4,550 feet per minute (23.11 meters per second) at Sea Level. Its maximum unrefueled range was 7,015 miles (11,290 kilometers).

Pilot’s cockpit, Boeing XB-52. (Boeing)
Boeing XB-52 Stratofortress 49-230. (U.S. Air Force)
Boeing XB-52 Stratofortress 49-230. (U.S. Air Force)
Boeing XB-51 Stratofortress 49-230 with a North American F-86 Sabre chase plane. (U.S. Air Force)
Boeing XB-52 Stratofortress 49-230 with a North American F-86 Sabre chase plane. (U.S. Air Force)
Boeing XB-52 Stratofortress 49-230. (U.S. Air Force)
Boeing XB-52 Stratofortress 49-230. (U.S. Air Force)

In its original configuration, the XB-52 was armed with two .50-caliber machine guns in a turret in the tail, with 600 rounds of ammunition per gun, though these guns were not installed on 49-230. The XB-52 was designed to carry a single 25,200 pound (11,431 kilogram) T-28E2 Samson bomb, or other conventional or nuclear weapons.

XB-52 49-230 was used in flight testing for its entire service life. The airplane was scrapped in the mid-1960s.

744 B-52 bombers were built by Boeing at Seattle, Washington and Wichita, Kansas, with the final one, B-52H-175-BW 61-0040, rolled out 22 June 1962.

75 B-52H Stratofortresses are still in service with the United States Air Force.

Boeing XB-52, with Tex Johnston and Guy Townsend in the tandem cockpit. (Boeing)
Boeing XB-52 Stratofortress 49-230 (U.S. Air Force)
Boeing XB-52 Stratofortress 49-230 with two Pratt & Whitney J75 turbojets in single-engine nacelles on the outer pylons, circa 1959. (U.S. Air Force)

© 2017 Bryan R. Swopes

29 September 1965

The Strategic Air Command’s very first operational Boeing B-52, Boeing RB-52B-15-BO Stratofortress 52-8711. (Angelfire)

29 September 1965: Ten years after it entered service, the first operational Boeing B-52 Stratofortress, RB-52B-15-BO 52-8711, was retired to the Strategic Aerospace Museum, Offutt Air Force Base, Nebraska.

The first operational B-52 Stratofortress, RB-52B-15-BO 52-8711. (U.S. Air Force)
The first operational B-52 Stratofortress, RB-52B-15-BO 52-8711. (U.S. Air Force)

52-8711 had arrived at Castle Air Force Base, California, 29 June 1955, and was assigned to the 93rd Bombardment Wing (Heavy). It later served with the 22nd Bombardment Wing (Heavy) at March Air Force Base, California.

Boeing RB-52B-15-BO Stratofortress 52-8711, 22 Bombardment Wing (Heavy), March AFB, 1965. Compare this photograph to the image above. (U.S. Air Force)
Boeing RB-52B Stratofortress on display at Offutt Air Force Base, Nebraska. (Wikimedia)

© 2019, Bryan R. Swopes

21 September 1964

North American Aviation XB70A-1-NA 62-001 takes off for the first time, 21 September 1964. (U.S. Air Force)
North American Aviation XB70A-1-NA 62-0001 takes off for the first time, 21 September 1964. (U.S. Air Force)

21 September 1964: The first prototype North American Aviation XB-70A-1-NA Valkyrie, serial number 62-0001, flown by Chief Test Pilot Alvin S. White and Colonel Joseph F. Cotton, U.S. Air Force, made its first flight from Air Force Plant 42, Palmdale, California, to Edwards Air Force Base.

Originally a prototype Mach 3 strategic bomber, 62-0001 (also known as AV-1) and it’s sister ship, XB-70A-2-NA, 62-0207, (AV-2), were built and used by the Air Force and NASA as high-speed research aircraft. The third Valkyrie, XB-70B-NA 62-0208 (AV-3), was never completed.

Major Joseph F. Cotton, USAF, and Alvin S. White, North American Aviation, with the XB-70A Valkyrie. (Autographed photograph courtesy of Neil Corbett, TEST & RESEARCH PILOTS, FLIGHT TEST ENGINEERS)
Colonel Joseph F. Cotton, USAF, and Alvin S. White, North American Aviation, with an XB-70A Valkyrie. (Autographed photograph courtesy of Neil Corbett, TEST & RESEARCH PILOTS, FLIGHT TEST ENGINEERS)

62-0001 was the first of three prototype Mach 3+ strategic bombers. (The third prototype, XB-70B 62-0208, was not completed.) The Valkyrie utilized the most advanced technology available. Materials and manufacturing techniques had to be developed specifically to build this airplane. It is a large delta wing airplane with a forward canard and two vertical fins. 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.

The XB-70A is 185 feet, 10 inches (56.642 meters) long with a wingspan of 105 feet (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). The delta wing had 0° angle of incidence and 0° dihedral. (The second XB-70A had 5° dihedral.) The wing has 3.0° negative twist. At 25% chord, the wing has 58.0° sweepback. Total wing area is 6,297 square feet (585 square meters). The Valkyrie has a empty weight of 231,215 pounds (104,877 kilograms), and maximum takeoff weight (MTOW) of 521,056 pounds (2236,347 kilograms).

It is powered by six General Electric YJ93-GE-3 turbojet engines. The J93 is an afterburning single-shaft axial-flow turbojet with an 11-stage compressor section and two-stage turbine. It has a Normal Power rating of 17,700 pounds of thrust (78.73 kilonewtons), 19,900 pounds (88.52 kilonewtons), Military, and 28,000 pounds (124.55 kilonewtons) Maximum. (All ratings are continuous, at 6,825 r.p.m.) The YJ93-GE-3 is 236.3 inches (6.002 meters) long, 54.15 inches (1.375 meters) in diameter, and weighs 5,220 pounds (2,368 kilograms).

A Boeing B-52 Stratofortress flies formation with North American Aviation XB-70A Valkyrie 62-0001, approaching the runway at Edwards Air Force Base, California. (U.S. Air Force)

The maximum speed achieved was Mach 3.08 (1,787 knots/2,056 miles per hour, or 3,309 kilometers per hour) at 73,000 feet (22,250 meters), 12 April 1966. Its mission maximum speed is 1,721 knots (1,980 miles per hour/3,187 kilometers per hour) at 79,050 feet (29,094 meters). The XB-70A has a rate of climb of 33,000 feet per minute (168 meters per second). The service ceiling is 79,000 feet (24,079 meters).

North American Aviation XB-70A Valkyrie 62-0001 lost approximately 15% of its paint during its third test flight, 12 October 1964—its first supersonic flight. United States Air Force)

The Valkyrie has a maximum fuel capacity of 43,646 gallons (165,218 liters) JP-5 or JP-6, carried in 11 tanks throughout the fuselage and wings. It also carries 42.4 gallons (161 liters) of engine oil. The maximum range is 2,969 nautical miles (3,417 statute miles/5,499 kilometers).

North American Aviation XB-70A Valkyrie 62-0001 made 83 flights with a total of 160 hours, 16 minutes flight time. 62-0001 is on display at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio.

North American Aviation XB-70A Valkyrie 62-0001 lands at Edwards Air Force Base at the end of its first flight, 21 September 1964. (U.S. Air Force)
North American Aviation XB-70A-1-NA Valkyrie 62-0001 just before landing at Runway 4 Right, Edwards Air Force Base, ending of its first flight, 21 September 1964. A Piasecki HH-21B rescue helicopter hovers over the adjacent taxiway. (U.S. Air Force)

© 2024, Bryan R. Swopes