On a true motion display, which of the following will appear to move across the PPI scope?

On a true motion display, which of the following will appear to move across the PPI scope?

• A. Echo from a ship at anchor
• B. Own ship's marker
• C. Echoes from land masses
• D. All of the above

Answer: (B)

In a true motion display, the representation of a vessel's movement is shown relative to a fixed background, meaning that the own ship’s marker is the only element that appears to move across the PPI (Plan Position Indicator) scope. This display is designed to reflect the own ship’s position and trajectory, giving the navigator a clear view of how the vessel is progressing through its environment. In this context, echo returns from other ships, such as a ship at anchor, would remain stationary on the screen, as their movement relative to the own ship is not represented in a true motion display. Similarly, land masses and geographical features are also fixed and would not appear to move. Therefore, the correct representation of movement on a true motion display pertains only to the marker for the own ship, which goes across the PPI scope according to its navigational path.

In a true motion display, the representation of a vessel's movement is shown relative to a fixed background, meaning that the own ship’s marker is the only element that appears to move across the PPI (Plan Position Indicator) scope. This display is designed to reflect the own ship’s position and trajectory, giving the navigator a clear view of how the vessel is progressing through its environment.

In this context, echo returns from other ships, such as a ship at anchor, would remain stationary on the screen, as their movement relative to the own ship is not represented in a true motion display. Similarly, land masses and geographical features are also fixed and would not appear to move. Therefore, the correct representation of movement on a true motion display pertains only to the marker for the own ship, which goes across the PPI scope according to its navigational path.