How long can a SR-71 blackbird fly at its top speed before it needs refueling?

The SR-71 Blackbird has two Pratt & Whitney J58 turbojet engines that gave it the incredible speed and altitude for which it was known. Its top speed was Mach 3.2, or 2,200 miles per hour. With refueling, the Blackbird could fly long distances, however, it had a relatively limited unrefueled range. The SR-71's unrefueled range varied depending on the mission and flight conditions, but it was typically around 2,400 miles (3,860 kilometers). For longer missions, the SR-71 relied on in-air refueling from tanker aircraft.