The SR-71 Blackbird was designed by Clarence Kelly Johnson. This strategic reconnaissance aircraft took its first flight on the 22nd of December, 1964. The top speed of SR-71 Blackbird is Mach 3.5. It has fly at an altitude higher than 100,000 feet. Moreover, its range is 4,000 miles. The Blackbird takes only one hour to conduct a survey of 100,000 square miles of the surface of the earth.