“The Lockheed YF-12A was undoubtedly the most advanced…

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“The Lockheed YF-12A was undoubtedly the most advanced interceptor ever built by the United States and was capable of Mach 3 at altitudes exceeding 80,000 feet. The aircraft was equipped with a longrange radar and three Hughes AIM-47 Falcon missiles with nuclear warheads. Weapons systems tests proved remarkably successful, and after the YF-12 program was cancelled, the radar and missiles formed the basis of the system used on the Grumman F-14 Tomcat” (via)