History Hour: the last of 744 Boeing B-52 Stratofortress
22 June 1962: The last of 744 Boeing B-52 Stratofortress strategic bombers, B-52H-175-BW, serial number 61-0040, was rolled out at the Boeing Military Airplane Company plant in Wichita, Kansas.
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 Wichita.
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 B-52H, like the B-52G, is a re-engineered aircraft, structurally different from the XB-52, YB-52, and B-52A–B-52F Stratofortresses. The bomber is lighter and carries more internal fuel, giving it a longer unrefueled range, and it is strengthened for low-altitude flight.
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 program was cancelled, however, and the North American Aviation AGM-28 Hound Dog air-launched cruise missile was used instead.
Boeing B-52H-175-BW Stratofortress 61-0040 in camouflage, assigned to 2nd Air Force, circa 1975. (U.S. Air Force)
The B-52H is a sub-sonic, swept wing, long-range strategic bomber. Like the previous B-52s, the B-52H was operated by a crew of six: two pilots, a navigator and a radar navigator, an electronic warfare officer, and a gunner. The bomber is 156 feet, 0 inches (47.549 meters) long with a wingspan of 185 feet, 0 inches (56.388 meters) and overall height of 40 feet, 8 inches (12.395 meters). The B-52H uses the vertical fin developed for the B-52G, which is 22 feet, 11 inches (6.985 m) 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 shorter vertical fin was intended to prevent the aircraft crashes caused by the original tall fin failing in turbulent air.
The bomber has an empty weight of 172,740 pounds (78,354 kilograms) and a maximum takeoff weight of 488,000 pounds (221,353 kilograms).
Boeing B-52H Stratofortress. (U.S. Air Force)
The B-52 has eight Pratt & Whitney TF33 turbofan engines mounted in two-engine nacelles suspended under the wings and on four pylons. The most significant difference between the B-52H and the earlier Stratofortresses is the replacement of the J57 turbojet engines with Pratt & Whitney TF33-P-3 turbofans, which are significantly more efficient. They are also quieter and don’t emit the dark smoke trails of the turbojets. They are rated at 17,000 pounds of thrust, each, for takeoff.
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)—0.90 Mach—at a combat weight of 306,350 pounds (138,958 kilograms). The service ceiling is 47,700 feet (14,539 meters). With inflight refueling, the bomber’s range is limited only by the endurance of its crew. The service ceiling is 47,700 feet (14,539 meters) at combat weight. The unrefueled range is 8,000 miles (12,875 kilometers).
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 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 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).
Boeing B-52H-175-BW Stratofortress 61-0040 parked at Andersen Air Force Base, Guam. (U.S. Air Force)
102 B-52Hs were built by Boeing Wichita. 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.
54 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.
*A B-52H, 60-0047, 69th Expeditionary Bomb Squadron, crashed and was destroyed by fire during takeoff at Anderson AFB, Guam, 18 May 2016.
On the main photo: A Boeing B-52H Stratofortress during a deterrent patrol near the Democratic People’s Republic of North Korea, 2016. (U.S. Air Force)
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