its still classified - the USAF/NASA will only admit to 2,193.17 mph; 3,529.56 km/h but every time some new plane challenged the record, they just sent up an official mission to beat the standing record at the time. Nothing ever beat it.
3.5
2200 mph
About 3 times the speed of sound. (3 mach)
Black
The SR-71 Blackbird is 2,193 miles per hour fast or Mach 3, three times faster than the speed of sound.
2193 mph
Stratosphere
the stratosphere!
The SR-71 Blackbird was introduced into service in 1966.
It is the Lockheed SR-71 "Blackbird", a reconnaissance aircraft.
SR71 Blackbird Model M-21: maximum speed: 2211miles/h Generally, the given answer for all models of the SR71 is: "In excess of Mach 3", or more than three times the speed of sound. see related links below for more info
No it just flew very high to avoid radar.