Radar Observer · Limitations — Shadow
Shadow (blind) sectors on a vessel's radar are areas where:
- ATargets appear twice
- BObstructions such as masts or funnels block the beam, weakening or hiding echoes✓ Correct
- CThe radar performs best
- DOnly rain shows
Explanation
Structures like masts and funnels can block or weaken the beam in certain directions, creating shadow sectors where targets may be missed or reduced. These sectors should be known and covered by other means.
Authority: Radar Limitations (USCG topic)
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