https://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress
The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic
bomber. The B-52 was designed and built by Boeing, which has continued to
provide support and upgrades. It has been operated by the United States Air
Force (USAF) since the 1950s. The bomber is capable of carrying up to 70,000
pounds (32,000 kg) of weapons, and has a typical combat range of more than 8,800
miles (14,080 km) without aerial refueling.
Beginning with the successful contract bid in June 1946, the B-52 design evolved
from a straight wing aircraft powered by six turboprop engines to the final
prototype YB-52 with eight turbojet engines and swept wings. The B-52 took its
maiden flight in April 1952. Built to carry nuclear weapons for Cold War-era
deterrence missions, the B-52 Stratofortress replaced the Convair B-36. A
veteran of several wars, the B-52 has dropped only conventional munitions in
combat. The B-52's official name Stratofortress is rarely used; informally, the
aircraft has become commonly referred to as the BUFF (Big Ugly Fat Fucker).
The B-52 has been in active service with the USAF since 1955. As of 2012, 85
were in active service with nine in reserve. The bombers flew under the
Strategic Air Command (SAC) until it was disestablished in 1992 and its aircraft
absorbed into the Air Combat Command (ACC); in 2010 all B-52 Stratofortresses
were transferred from the ACC to the newly created Air Force Global Strike
Command (AFGSC). Superior performance at high subsonic speeds and relatively low
operating costs have kept the B-52 in service despite the advent of later, more
advanced aircraft, including the canceled Mach 3 B-70 Valkyrie, the
variable-geometry B-1 Lancer, and the stealth B-2 Spirit. The B-52 completed
sixty years of continuous service with its original operator in 2015. After
being upgraded between 2013 and 2015, it is expected to serve into the 2040s.
Role
Strategic bomber
National origin
United States
Manufacturer
Boeing
First flight
15 April 1952
Introduction
February 1955
Status
In service
Primary users
United States Air Force
NASA
Produced
Number built
744
Unit cost
B-52B: US$14.43 million (1956); US$126.93M (2016 with inflation)
B-52H: US$9.28M (1962); US$84M (2012 with inflation)
Developed into
Conroy Virtus
Although the B-52A was the first production variant, these aircraft were used
only in testing. The first operational version was the B-52B that had been
developed in parallel with the prototypes since 1951. First flying in December
1954, B-52B, AF Serial Number 52-8711, entered operational service with 93rd
Heavy Bombardment Wing (93rd BW) at Castle Air Force Base, California, on 29
June 1955. The wing became operational on 12 March 1956. The training for B-52
crews consisted of five weeks of ground school and four weeks of flying,
accumulating 35 to 50 hours in the air. The new B-52Bs replaced operational
B-36s on a one-to-one basis.
As of January 2013, 78 of the original 744 B-52 aircraft were operational in the
U.S. Air Force. Four of 18 B-52Hs from Barksdale AFB being retired are in the
"boneyard" of 309th AMARG at Davis-Monthan AFB as of 8 September 2008.
B-52s are periodically refurbished at USAF maintenance depots such as Tinker Air
Force Base, Oklahoma. Even while the air force works on a new bomber, it intends
to keep the B-52H in service until 2045, nearly 90 years after the B-52 first
entered service, an unprecedented length of service for any aircraft, civilian
or military.
The USAF continues to rely on the B-52 because it remains an effective and
economical heavy bomber in the absence of sophisticated air defense,
particularly in the type of missions that have been conducted since the end of
the Cold War against nations with limited defensive capabilities. The B-52 has
also continued in service because there has been no reliable replacement. The
B-52 has the capacity to "loiter" for extended periods, and can deliver
precision standoff and direct fire munitions from a distance, in addition to
direct bombing. It has been a valuable asset in supporting ground operations
during conflicts such as Operation Iraqi Freedom. The B-52 had the highest
mission capable rate of the three types of heavy bombers operated by the USAF in
B-2 Spirit achieved 30.3%, while the B-52 averaged 80.5%. The B-52's $72,000
cost per hour of flight is more than the B-1B's $63,000 cost per hour, but less
than the B-2's $135,000 per hour.
Specifications (B-52H)
General characteristics
Crew: 5 (Pilot, Copilot, Weapon Systems Officer, Navigator, Electronic Warfare
Officer, and Tail gunner until the removal of the tail gun in 1991)
Length: 159?ft 4 in (48.5?m)
Wingspan: 185?ft 0?in (56.4?m)
Height: 40?ft 8?in (12.4?m)
Airfoil: NACA 63A219.3 mod root, NACA 65A209.5 tip
Empty weight: 185,000 lb (83,250 kg)
Loaded weight: 265,000 lb (120,000 kg)
Max. takeoff weight: 488,000 lb (220,000 kg)
Fuel capacity: 47,975 U.S. gal (39,948 imp gal; 181,610 L)
Zero-lift drag coefficient: 0.0119 (estimated)
Aspect ratio: 8.56
Performance
Maximum speed: 560 kn (650 mph, 1,047 km/h)
Cruise speed: 442 kn (525 mph, 844 km/h)
Combat radius: 4,480 mi (3,890 nmi, 7,210 km)
Ferry range: 10,145 mi (8,764 nmi, 16,232 km)
Service ceiling: 50,000 ft (15,000 m)
Rate of climb: 6,270 ft/min (31.85 m/s)
Thrust/weight: 0.31
Lift-to-drag ratio: 21.5 (estimated)
Armament
controlled tail turret on the H-model, removed from all current operational
aircraft in 1991
Bombs: Approximately 70,000 lb (31,500 kg) mixed ordnance; bombs, mines,
missiles, in various configurations.
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