🔍 Key Concepts

• Current set and drift and how they affect your course over ground vs. course steered • Using a current triangle (or vector triangle) to combine ship’s motion and current • Difference between true course and gyrocompass course (including any gyro error if given)

💭 Think About

• First sketch or visualize the vector for your intended course and speed through the water, then add the current vector (set and drift). Which way does the current push you relative to your desired track? • Ask yourself: to end up on 204°T over the ground, do you need to steer into the current (up‑current) or with it (down‑current)? What does that do to your heading number—higher or lower than 204°? • Consider whether any gyro error or variation/deviation corrections are mentioned. If not, how does that simplify the conversion between true and gyro?

✅ Before You Answer

• Make sure you draw the current vector from the tip of your ship’s motion vector, not from the origin, when constructing the current triangle. • Verify the relative angle between the ship’s heading and the current set: is the current coming from ahead, astern, port, or starboard? That determines which side you must steer toward. • Check whether the problem provides any gyro error, variation, or deviation. If none is given, think about what relationship you can assume between true course and gyro course for exam purposes.