| Answer | Crossword Clue |
|---|---|
| SNORKEL | Ventilation for submarines. |
| SNORKEL | Device for submarines. |
| DETECTORS | Devices for locating submarines. |
| SONAR | Location device for submarines. |
| SONAR | Method for detecting submarines |
| SONAR | Echo device for locating submarines. |
| ILELONGUE | Base off the coast of Brest for France's nuclear submarines |
