City Sailing · video

What this video covers

Radar plotting on a paper plotting sheet determines the Closest Point of Approach (CPA), Time to Closest Point of Approach (TCPA), and the course and speed of a target vessel.0:16 Using a radar simulator, the operator records an initial target position at 6.03 miles and 304 degrees relative, then takes a second position six minutes later at 4.37 miles and 308 degrees relative.0:36 Because six minutes represents one-tenth of an hour, the distance traveled by the target in that interval, when multiplied by ten, provides the target's speed.6:39 By accounting for the operator's own ship course of 040 degrees true and speed of 6 knots, the plotter resolves the target's true course and speed.6:17 In this scenario, the target maintains a CPA of 1 nautical mile in 13 minutes.4:50 Under Rule 19 of the International Regulations for Preventing Collisions at Sea, when a vessel is detected forward of the beam in restricted visibility, the operator must avoid altering course to port and should instead alter to starboard.10:38

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