Radar Observer · Limitations — Indirect (False) Echoes
An indirect echo (false target from reflection off own ship's structure) can usually be recognized because it:
- AIs always brighter than the real target
- BAppears at the same range as the real target but on the bearing of the reflecting obstruction, and behaves erratically✓ Correct
- CNever moves
- DOnly appears at maximum range
Explanation
An indirect echo is produced when the beam reflects off a mast or funnel before/after hitting a real target, so the false echo shows at the correct range but in the direction of the reflecting structure (often within a blind sector). It typically appears intermittently and disappears as geometry changes — recognizing it prevents needless maneuvers.
Authority: Bowditch (Pub. No. 9), Radar Limitations
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