In the transition from supersonic to subsonic flight the aircraft breaks the sound barrier again?

Question

In the transition from supersonic to subsonic flight the aircraft breaks the sound barrier again?

Answer 1

The speed of sound is not a barrier.

Answer 2

I am a pilot, but I've never broken mach, but I checked with someone who has.  He said you get the effect on breaking it (speed increasing) but not on the way back down (speed decreasing). He flew USAF F94's (I think) and only did it a couple of times.  He said sometimes it might sound like a double boom in the cockpit.