Lockheed A-12

Lockheed A-12. . , The A-12 was the product of Project Oxcart, a secret military program to develop a high-speed, high-altitude reconnaissance aircraft. First flown in 1962, the A-12 was built by Lockheed's Advanced Development Projects office, now known as Skunk Works. The A-12 was capable of performing sensitive intelligence-gathering missions while flying at speeds over Mach 3, or three times the speed of sound. The Central Intelligence Agency (CIA) used A-12s for surveillance missions until 1968. Later versions, known as the SR-71 Blackbird, served in reconnaissance and test missions for the U.S. Air Force and NASA through the 1990s., Flown by CIA pilots, the A-12 was used for strategic reconnaissance over North Vietnam between May 1967 and March 1968. Its primary objective was to look for suspected surface-to-surface missile (SSM) sites. Evidence of SSM facilities was never found, but the A=12 did determine the location of many surface-to-air missile (SAM) sites and other strategically important targets. In total, A-12s were flown on 24 missions over Hanoi and the port city of Haiphong. SAMs were fired at the A-12 on two occasions. Other than some minor shrapnel damage to one aircraft, the A-12s survived unscathed., The A-12 on display, code-named Article 122, served as a radar-test example early in 1962 at the secluded test site known as Area 51, near Groom Lake, Nevada. A special radar signature-lowering paint covered the most titanium airframe, which also incorporated radar-absorbing materials. Massive Pratt and Whitney J58 turbo-ramjet engines powered the plane. these engines were used only in the A-12 and the SR-71 Blackbird., The adjacent yellow starter cart used a connecting drive shaft to spin the engines at up to 3,200 revolutions per minute and initiate the ignition cycle of the turbo-ramjet engines. The cart uses two Buick 401 cubic-inch "Wildcat" V-8 automobile engines of 350 horsepower, similar to those used in American "muscle cars" of the era.,

Length: 102 feet (31 m) , Wingspan: 55 feet 7 inches (16.9 m) , Height: 18 feet 3 inches (5.5 m) , Empty Weight: 54,600 pounds (24,766 kg) , Max Weight: 120,000 pounds (54,431 kg) , Top Speed: 2,269 miles per hour (3,651 kph) , Ceiling: 95,000 feet (28,956 m) , Crew: One , Armament: 2,500 pounds (1,134 kg) of imaging sensors

, [Captions:] , The massive Pratt and Whitney J58 turbo-ramjet engines used the onboard fuel supply very quickly, so in-flight refueling was an essential part of A-12 operations. To accomplish this, the KC-135 tanker, shown here, had to fly at its maximum speed while the A-12 approached stall speed, the minimum speed required to maintain flight., The pointed parts at the front of each jet engine intake are called shock cones. Without shock cones, air entering the engine inlets would extinguish the jet engines when flying at supersonic speeds. The shock cones create a shock wave that slows the incoming air so that the engine can use it efficiently.