Radar Observer · Limitations — Shadow
A blind or shadow sector on a vessel's radar is caused by:
- ARain on the antenna
- BObstructions such as masts or stacks blocking the beam in certain directions✓ Correct
- CLow gain settings
- DA mistuned receiver
Explanation
Superstructure, masts, and funnels block or attenuate the beam in some bearings, creating shadow sectors where targets are weak or missing. These sectors must be known and covered by other lookout means.
Authority: Radar Navigation — Limitations
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