Going too quick...
Sat in the tower watching what ATC do while I was converting to the Wessex (somebody had decided it was a good idea). Area controller talking to an F-111 and trying to get clearance for it to cross an airway. London Military aren't answering the phone and it's getting tight.
Eventually ATCO says "There's no traffic, so I'll count you into the airway and when you're in go to full throttle to minimise the time you're there." This seems sensible and all goes quite well. ATCO tells the F-111 that he's clear and the Aardvark resumes normal flight. Then the message comes through "Err...I think I may have gone supersonic back there."
There's a pause. It's a long pause. Then the Approach Room Supervisor picks up the mic. "We won't tell if you don't. Good day."