The YF-12 was developed in the 1960s as a high-altitude, Mach 3 interceptor to defend against supersonic bombers. Based on the A-12 reconnaissance aircraft, the YF-12A became the forerunner of the highly-sophisticated SR-71 strategic reconnaissance aircraft.
The first of three YF-12s flew in August 1963. In May 1965, the first and third YF-12s set several records, including a speed record of 2,070.101 mph and an altitude record of 80,257.65 feet. For their speed record flight, Col. Robert L. "Fox" Stephens (pilot) and Lt. Col. Daniel Andre (fire control officer) received the 1965 Thompson Trophy.
Though the aircraft performed well, the F-12 interceptor program ended in early 1968. High costs, the ongoing war in Southeast Asia, and a lower priority on air defense of the US all contributed to the cancellation.
The aircraft on display -- the second one built -- was recalled from storage in 1969 for a joint USAF/NASA investigation of supersonic cruise technology. It was flown to the museum in 1979, and it is the only remaining YF-12A in existence (the first YF-12A was damaged beyond repair after a landing mishap, and the third YF-12A was destroyed after the crew ejected to escape an inflight fire).
Armament: Three Hughes AIM-47A missiles
Engines: Two Pratt & Whitney J58s of 32,000 lbs. thrust each (with afterburner)
Maximum speed: Mach 3+
Range: 2,000+ miles
Service ceiling: Above 80,000 feet
Weight: 127,000 lbs. loaded
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