| Answer | Crossword Clue |
|---|---|
| SUPERSONIC | Past the sound barrier. |
| ENCROACHED | Went past the barrier |
| SONIC | Designating the sound barrier. |
| MACHI | Speed at the sound barrier. |
| YEAGER | Chuck who broke the sound barrier |
| SST | It's not breaking the sound barrier anymore |
| BOOM | Sound made when passing the sound barrier |
| COCHRAN | First aviatrix to break the sound barrier Jacqueline .. |
| WHIP | First object made by humans to break the sound barrier |
