Related Clues:
- GPS predecessor
- Nautical mapping tool
- Shipwreck hunter's device
- Naval navigation device
- Counterpart of radar
- Detection system with pings
- Dolphin communication method
- Underwater navigation tool
- Sub’s navigational technique
- Device for locating sunken objects
- Dolphin's detection process
- System for detecting the pulses found in Ferguson, Arkansas
- Instrument carried by fliers on a raid
- Nautical navigation tool
- Sound navigation and ranging system