The XB-70 Valkyrie, with a planned cruise speed of Mach 3 and operating altitude of 70,000 feet, was to be the final high-altitude, high-speed manned strategic bomber. However, this would cause to play a far different role in the history of aviation.
To achieve Mach 3 performance, the B-70 was proposed to "ride" its own shock wave, much as a surfer rides an ocean wave. The resultant shape used a delta wing on a slab-sided fuselage that controlled the six jet engines that powered the aircraft where as the outer wing panels were hinged.
During the take off, landing and subsonic flight, they remained in the horizontal position. This feature increased the amount of lift created, improving the lift-to-drag ratio. Once if the aircraft was supersonic, the wing panels would be hinged downward. By changing the position of the wing panels it can reduce the drag caused by the wingtips interacted with the inlet shock wave.
These repositioned wingtips can also reduce the area behind the airplane's center of gravity, which in turn reduce the trim drag. The down turned outer panels will also provide more vertical surface to improve directional stability at high Mach numbers attached to the delta was a long, thin forward fuselage. At the rear the cockpit were two large canards, which acted as control surfaces.
As an inspiring technological feat the B-70 represented, the aircraft that was under development at the time when the future of the manned bomber was uncertain. During the late 1950s and early 1960s, many had felt that manned aircraft were obsolete, and the future belonged to missiles. As a result, the Kennedy Administration had ended the plans to deploy the B-70. Two experimental XB-70A prototypes were under the construction at North American Aviation when the program was canceled.
Simultaneously there was a growing interest in an American supersonic transport (SST); Jet airliners had cut the flight times by more than half in comparison to propeller-powered aircraft. A Mach 2 or 3 SST could make a comparable improvement over the new subsonic jet airliners. The Flight Research Center had several SST studies during the early 1960s where as, the NASA's Douglas F5D-1 was used for landing studies, a North American F-100C was modified to simulate SST handling qualities, a North American A-5A was used to simulate an SST for tests of the air traffic control system, and a Lockheed JetStar was modified as an in-flight SST simulator.
To achieve Mach 3 performance, the B-70 was proposed to "ride" its own shock wave, much as a surfer rides an ocean wave. The resultant shape used a delta wing on a slab-sided fuselage that controlled the six jet engines that powered the aircraft where as the outer wing panels were hinged.
During the take off, landing and subsonic flight, they remained in the horizontal position. This feature increased the amount of lift created, improving the lift-to-drag ratio. Once if the aircraft was supersonic, the wing panels would be hinged downward. By changing the position of the wing panels it can reduce the drag caused by the wingtips interacted with the inlet shock wave.
These repositioned wingtips can also reduce the area behind the airplane's center of gravity, which in turn reduce the trim drag. The down turned outer panels will also provide more vertical surface to improve directional stability at high Mach numbers attached to the delta was a long, thin forward fuselage. At the rear the cockpit were two large canards, which acted as control surfaces.
As an inspiring technological feat the B-70 represented, the aircraft that was under development at the time when the future of the manned bomber was uncertain. During the late 1950s and early 1960s, many had felt that manned aircraft were obsolete, and the future belonged to missiles. As a result, the Kennedy Administration had ended the plans to deploy the B-70. Two experimental XB-70A prototypes were under the construction at North American Aviation when the program was canceled.
Simultaneously there was a growing interest in an American supersonic transport (SST); Jet airliners had cut the flight times by more than half in comparison to propeller-powered aircraft. A Mach 2 or 3 SST could make a comparable improvement over the new subsonic jet airliners. The Flight Research Center had several SST studies during the early 1960s where as, the NASA's Douglas F5D-1 was used for landing studies, a North American F-100C was modified to simulate SST handling qualities, a North American A-5A was used to simulate an SST for tests of the air traffic control system, and a Lockheed JetStar was modified as an in-flight SST simulator.
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