Originally shared by +Gazing Skyward TV August 7th, 1963First flight of the Lockheed YF-12. The Lockheed YF-12 was an American prototype interceptor aircraft evaluated by the United States Air Force. The YF-12 was a twin-seat version of the secret single-seat Lockheed A-12 reconnaissance aircraft, which led to the U.S. Air Force's Lockheed SR-71 Blackbird twin-seat reconnaissance variant. The YF-12 set and held speed and altitude world records of over 2,000 mph and over 80,000 ft (later surpassed by the SR-71), and is the world's largest manned interceptor to date….. Source:Wikipedia, Lockheed YF-12: http://gstv.us/1J0jCND YouTube, The Lockheed YF-12: http://gstv.us/1J0jBta If you enjoy the "This Day in Aviation History" collection, you may enjoy some of these other collections from Gazing Skyward TV: http://gstv.us/GSTVcollections Photo from: http://gstv.us/2aZM5c7 #avgeek #Lockheed #YF12 #military #USAF #USA #aviation #history #fb