City Sailingvideo
Radar Plotting a Stationary Buoy and Ship part of City Sailing Ship Bridge Simulator Series
February 25, 2025 · 11 min · 377 views
What this video covers
Radar plotting on a ship bridge simulator demonstrates how to distinguish between stationary objects and moving vessels using relative motion. A stationary buoy appears on the radar screen moving parallel to the vessel’s heading line at the same speed and course as the ship. By applying continuous echo trails to the radar display, a navigator can visualize this relative motion. To determine the true movement of another vessel, the navigator must subtract the ship’s own course and speed—represented by the stationary buoy’s track—from the target’s relative movement. This process allows for the calculation of the Closest Point of Approach (CPA) and the Time to Closest Point of Approach (TCPA). Using a Variable Range Marker (VRM) and an Electronic Bearing Line (EBL) on the radar interface provides precise measurements for these values. The exercise assumes both vessels maintain a constant course and speed during the encounter.
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