Related Clues:
- Fish-finding tool
- Ship's detection system
- Nautical echo sounder
- Shipwreck detector
- Fly, carrying new tracking apparatus
- Younger relative is given a hand system for underwater detection
- Echo-location
- Sound-based detection system
- It detects its echo on substrata or foundations
- Bat signal
- Dolphin's facility
- Dolphins' communication method
- Fly high having installed new navigation system
- Underwater navigational aid
- Undersea detection system