| Answer | Crossword Clue |
|---|---|
| ECHOES | They travel at the speed of sound |
| UFOS | They might travel at warp speed |
| CHUCKYEAGER | First pilot to travel faster than the speed of sound |
| SONIC | "Service at the Speed of Sound" franchise |
| EXOCET | Anti-ship missile that skims waves at nearly the speed of sound |
| MACHI | Speed at the sound barrier. |
