"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 525 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 1,742 knots on the
ground.' We did not hear another transmission on that frequency all
the way to the coast."

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