Radar Observer · Propagation — Ducting
Super-refraction (ducting) of the radar beam tends to:
- AReduce detection range below normal
- BBend the beam downward and increase detection range beyond the horizon✓ Correct
- CHave no effect on range
- DEliminate sea clutter
Explanation
Super-refraction occurs when temperature/humidity gradients bend the beam more sharply toward the surface, extending detection range. Sub-refraction does the opposite, bending the beam up and shortening range.
Authority: Radar Navigation — Propagation
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