🔍 Key Concepts
• Rule 13 – Overtaking: How do you know if one vessel is overtaking another? Think about the 22.5° abaft the beam definition and relative position to the stern light.
• Rule 15 – Crossing Situation: When two power-driven vessels are crossing, which one is the give-way vessel and which is the stand-on vessel? It depends on which side the other vessel is seen from.
• Relative bearings: From each vessel’s heading, decide whether the other vessel is ahead, abeam, or abaft the beam.
💭 Think About
• From vessel II’s point of view, in the picture, is vessel I mostly off her bow, beam, or stern? Would II see I’s stern light only, or also sidelights?
• If this is a crossing situation, which vessel has the other on her starboard side? Remember that the vessel with the other on her starboard must keep out of the way.
• Ask yourself: Are you (on vessel I) coming up from behind vessel II on roughly the same course, or are your courses meeting at an angle? That decides if choice B can apply.
✅ Before You Answer
• Verify whether the relative position of vessel I to vessel II fits the Rule 13 overtaking definition (more than 22.5° abaft the beam). If it does not, eliminate choice B.
• Confirm if the situation matches Rule 15 – Crossing (two power-driven vessels on crossing courses with risk of collision). If it does, then one must be stand-on and the other give-way.
• Determine clearly which vessel sees the other on her starboard side; that vessel will be the give-way vessel, and the other will be the stand-on vessel.