Which scenario allows detection of inland mountains using radar from farther away?

• A. It is only possible at night
• B. Vessels farther from land may be able to detect mountains over the top of the coastal hills using RADAR
• C. It is impossible to detect inland mountains by radar
• D. Only when there is strong cloud cover

Answer: (B)

Radar visibility is governed by line-of-sight and height. The radar horizon grows as either the observer’s antenna height or the target’s height increases. Inland mountains that are tall enough can rise above the coastal hills and the Earth's curvature, so even from farther away you can still receive radar returns from them. In short, moving farther from land extends the distance at which tall terrain can be detected, especially when it protrudes above nearby coastal relief. Night or cloudy conditions don’t inherently change this geometric limit, and the existence of tall inland mountains makes detection possible rather than impossible.