Radar Observer · Performance — Detection Range
Your scanner's radar horizon is 9.8 NM and a target's radar horizon (for its height) is 6.2 NM. At about what range will the target first appear?
- A6.2 NM
- B9.8 NM
- C16.0 NM✓ Correct
- D3.6 NM
Explanation
A surface target is first detected at approximately the sum of the two radar horizons: 9.8 + 6.2 = 16.0 NM. A higher scanner or a taller target extends initial detection; low objects (small craft, buoys) appear much closer.
Authority: Bowditch (Pub. No. 9), Radar
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