What does North-up orientation indicate on a marine radar display?

What does North-up orientation indicate on a marine radar display?

• A. The top shows vessel heading and rotates with the ship
• B. The top shows true north at the top
• C. The top shows the course over ground and rotates with the ship
• D. The top is fixed to magnetic north

Answer: (B)

In North-up orientation the display is fixed to geographic directions, with the top of the screen pointing toward true north. This means the reference frame stays aligned with true north regardless of the ship’s heading, so readings and bearings on the screen relate directly to true bearings on the chart. The ship’s own symbol and targets move around the frame as you change course, rather than the entire image rotating to keep your heading at the top. If magnetic north were used, the top would point to magnetic north instead, which differs from true north. And in modes where the top represents the vessel’s course over ground or heading, the image would rotate with your ship instead of remaining fixed to true north.

In North-up orientation the display is fixed to geographic directions, with the top of the screen pointing toward true north. This means the reference frame stays aligned with true north regardless of the ship’s heading, so readings and bearings on the screen relate directly to true bearings on the chart. The ship’s own symbol and targets move around the frame as you change course, rather than the entire image rotating to keep your heading at the top. If magnetic north were used, the top would point to magnetic north instead, which differs from true north. And in modes where the top represents the vessel’s course over ground or heading, the image would rotate with your ship instead of remaining fixed to true north.