SUPER POWERFUL us air force Boeing B-52 Bomber Aircraft - WebTv
Eklenme Tarihi 1 yıl önce
This has been a great aircraft bomber for the Us air force 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.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 in informal circumstances, and it has become common to refer to the aircraft as the BUFF (Big Ugly Fat Fucker).[N 1]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 deactivated 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 new 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 fifty years of continuous service with its original operator in 2005; after being upgraded between 2013 and 2015, it is expected to serve into the 2040s.[N 2]DesignOverviewThe B-52 shared many technological similarities with the preceding Boeing B-47 Stratojet strategic bomber. The two aircraft used the same basic design, such as swept wings and podded jet engines, and the cabin included the crew ejection systems. On the B-52D, the pilots and electronic countermeasures (EDM) operator ejected upwards, while the lower deck crew ejected downwards; until the B-52G, the gunner had to jettison the tail gun to bail-out.Structural fatigue was accelerated by at least a factor of eight in a low-altitude flight profile over that of high-altitude flying, requiring costly repairs to extend service life. In the early 1960s, the three-phase High Stress program was launched to counter structural fatigue, enrolling aircraft at 2,000 flying hours. Follow-up programs were conducted, such as a 2,000-hour service life extension to select airframes in 1966–1968, and the extensive Pacer Plank reskinning, completed in 1977. The wet wing introduced on G and H models was even more susceptible to fatigue, experiencing 60% more stress during flight than the old wing. The wings were modified by 1964 under ECP 1050. This was followed by a fuselage skin and longeron replacement (ECP 1185) in 1966, and the B-52 Stability Augmentation and Flight Control program (ECP 1195) in 1967. Fuel leaks due to deteriorating Marman clamps continued to plague all variants of the B-52. To this end, the aircraft were subjected to Blue Band (1957), Hard Shell (1958), and finally QuickClip (1958) programs. The latter fitted safety straps that prevented catastrophic loss of fuel in case of clamp failure.In September 2006, the B-52 became one of the first US military aircraft to fly using alternative fuel. It took off from Edwards Air Force Base with a 50/50 blend of Fischer-Tropsch process (FT) synthetic fuel and conventional JP-8 jet fuel, which burned in two of the eight engines. On 15 December 2006, a B-52 took off from Edwards with the synthetic fuel powering all eight engines, the first time an air force aircraft was entirely powered by the blend. The seven-hour flight was considered a success. This program is part of the Department of Defense Assured Fuel Initiative, which aims to reduce crude oil usage and obtain half of its aviation fuel from alternative sources by 2016. On 8 August 2007, Air Force Secretary Michael Wynne certified the B-52H as fully approved to use the FT blend.AvionicsOngoing problems with avionics systems were addressed in the Jolly Well program, completed in 1964, which improved components of the AN/ASQ-38 bombing navigational computer and the terrain computer. The MADREC (Malfunction Detection and Recording) upgrade fitted to most aircraft by 1965 could detect failures in avionics and weapons computer systems, and was essential in monitoring the Hound Dog missiles. The electronic countermeasures capability of the B-52 was expanded with Rivet Rambler (1971) and Rivet Ace (1973).