Your vessel is proceeding up a channel, and you see a pair of range lights that are in line ahead. The chart indicates that the direction of this pair of lights is 196°T, and the variation is 7°E. If the heading of your vessel at the time of the sighting is 192° per standard magnetic compass, what is the deviation?

Question

Your vessel is proceeding up a channel, and you see a pair of range lights that are in line ahead. The chart indicates that the direction of this pair of lights is 196&deg;T, and the variation is 7&deg;E. If the heading of your vessel at the time of the sighting is 192&deg; per standard magnetic compass, what is the deviation?

Accepted Answer

Option B: 3&deg;W. The range lights provide a True bearing of 196°. With a variation of 7° E, the magnetic bearing is 189°. Given the vessel's magnetic compass heading of 192°, the deviation is the difference between the magnetic heading and the magnetic bearing, resulting in 3° W to correct the compass.