🔍 Key Concepts

• Light List abbreviations for aids to navigation types (e.g., daybeacons, ranges, junction marks) • Meaning of MR in the context of dayboards and ranges • How ranges are depicted and used for keeping a vessel on a line of position

💭 Think About

• What type of aid to navigation normally uses two dayboards that must be lined up visually by the mariner? • If you see "MR" associated with a dayboard in the Light List, does that suggest a single mark at a junction or a paired system used together? • How would your expected action change if the dayboard were indicating a junction versus indicating a line to steer on?

✅ Before You Answer

• Verify what "MR" specifically stands for in the Light List legend section (front of the volume). • Confirm whether an MR dayboard is associated with a range line or a junction/turning point. • Check how the Light List describes the use of this type of dayboard: does it direct you to choose a side, line up with another mark, or identify a junction?