The SR-71 Blackbird is hands-down my favorite jet. I may have to get a copy of this book, Sled Driver by Brian Shul, from which this anecdote is excerpted.
One day, high above Arizona, we were monitoring the radio traffic of all the mortal airplanes below us. First, a Cessna pilot asked the air traffic controllers to check his ground speed. ‘Ninety knots,’ ATC replied. A twin Bonanza soon made the same request. ‘One-twenty on the ground,’ was the reply. To our surprise, a navy F-18 came over the radio with a ground speed check. I knew exactly what he was doing. Of course, he had a ground speed indicator in his cockpit, but he wanted to let all the bug-smashers in the valley know what real speed was. ‘Dusty 52, we show you at 620 on the ground,’ ATC responded.
The situation was too ripe. I heard the click of Walter’s mike button in the rear seat. In his most innocent voice, Walter startled the controller by asking for a ground speed check from 81,000 feet, clearly above controlled airspace. In a cool, professional voice, the controller replied, ‘Aspen 20, I show you at 1,982 knots on the ground.’ We did not hear another transmission on that frequency all the way to the coast.
This is also an incredible idea to visualize:
Odd are the thoughts that wander through one’s mind in times like these. I found myself recalling the words of former SR-71 pilots who were fired upon while flying missions over North Vietnam. They said the few errant missile detonations they were able to observe from the cockpit looked like implosions rather than explosions. This was due to the great speed at which the jet was hurling away from the exploding missile.
SR-71: Now, That Was Some Airplane [Jobdig.com]