The SR-71 had its beginnings with 1954 CIA requirements for a successor to the U-2 spy plane. They wanted an aircraft that could travel over the Soviet Union at mach 3.2 at over 80,000 feet. The first version of the SR-71 (A-12) took to the air in 1962, and entered service in 1964. This title covers the history and development of the USAF's primary strategic reconnaissance aircraft of the Cold War era.