Which parameter does sea stabilized rely on?

• A. Course over ground and speed over ground
• B. Wind and current
• C. Distance to own ship
• D. Heading and speed through the water

Answer: (D)

Sea stabilization relies on the ship’s motion information to keep the sea background steady on the radar screen. The heading tells the stabilizing system which way the vessel is pointing, so the display can be oriented to the fore‑aft direction. The speed through the water tells the system how fast the ship is actually moving relative to the water, so the image can be shifted at the correct rate to compensate for that forward motion. With both heading and speed through water, the radar can remove the ship’s own movement from the scene, making sea clutter appear fixed and helping you spot real targets.

Using course over ground and speed over ground would tie stabilization to movement over the earth, which can be altered by currents and tides and would distort the display. Distance to own ship isn’t a parameter used to stabilize the sea background.