| Answer | Crossword Clue |
|---|---|
| SCRAMJETS | Supersonic plane engines |
| PHANTOMJET | Supersonic fighter plane |
| SST | Initials for supersonic plane. |
| FIII | New U.S. supersonic plane. |
| RAMJETS | Certain plane engines |
| NACELLE | Housing for plane engines. |
| ROAR | Plane engine's sound when taking off |
