More like 45 years.
it’s probably BS.
It is the word of the actual pilot and copilot of the SR-71. You would have to believe they both lied, and authorized putting it into a book based on their experience, to accept it as BS.
Military aircraft like this fly above class A airspace so civilian Air Traffic Controllers have no responsibility over them.
Correct. The tower was only reporting the groundspeed as measured on their radar equipment in response to a REQUEST FROM the SR-71 crew.
In addition, performance capabilities are classified info.
Yes, but there are things that you cannot hide. Like altitude and groundspeed measured by civilian radar. The pilots responding with their 'more accurate' speed revealed nothing that was not already known. That was proven by the tower response that he knew the SR-71's 'equipment' was more accurate. Most of that was due to the fact that not all airports had the most advanced radar equipment recently installed (because that is an impractical and almost impossible thing to do/expect). It gave away information that could only prove that the tower's equipment gave a different speed than the SR-71's, and any idiot could figure out that the SR-71 had more accurate equipment.
+1