🔍 Key Concepts

• IALA Cardinal Marks – shapes, topmarks, colors, and light rhythms for North, East, South, and West cardinals • Relative vs. true bearings – how to convert a relative bearing to a true bearing and then reverse it to see where you are in relation to the buoy • How cardinal marks indicate where the best water lies in relation to the danger (to the N, E, S, or W of the buoy)

💭 Think About

• First, convert the 021° relative bearing to a true bearing from your ship, then reverse it to find the true bearing of your ship from the buoy. In which general direction (N, E, S, or W) are you from the buoy? • Once you know whether you are north, east, south, or west of the buoy, which type of cardinal mark would you expect to see if you are currently in the best navigable water? • Match each answer choice to a specific cardinal mark (N, E, S, or W) using either the topmark, color bands, or light characteristic. Which option corresponds to the cardinal that has its safe water on your side of the buoy?

✅ Before You Answer

• Be sure you are using relative bearing correctly: measured from the ship’s head, clockwise 0–359°, then added to your true course to get a true bearing. • Double‑check the light characteristics: continuous Q or VQ vs. grouped quick flashes like Q(3), Q(6)+L Fl, Q(9), and their association with a particular cardinal mark. • Verify the color band patterns and topmark directions (both cones up, both down, bases together, points together) and tie each to the correct cardinal direction before choosing.