COLREG / ARPA / AIS Bridge Rule 7(b) Rule 7(c) Rule 19(d)(i) Rule 8 🔒 Course / Simulator plan

Radar — The True-Motion Trap (Rule 7(b))

Fog. On true motion with true vectors a ship on your starboard bow looks as if she will pass clear. Switch to relative motion and see the collision course.

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Scenario briefing

Fog. Your radar is on TRUE MOTION with TRUE vectors. A ship on your starboard bow: her vector points away across your bow — she looks as if she will pass clear. Will she? Rule 7(b): make proper use of the radar — switch to relative motion: a target closing on a steady bearing runs straight for the centre. Rule 7(c): no assumptions on scanty information. She is forward of the beam: Rule 19(d)(i) — no alteration to port; a bold alteration to starboard (astern of her) or reduce speed.

Applicable COLREG rule(s)

Rule 7(b) — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

Rule 7(c) — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

Rule 19(d)(i) — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

Rule 8 — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

Why it matters

COLREG knowledge is the foundation of safe ship handling. Most maritime collisions happen because watchkeepers either misidentified the situation, applied the wrong rule, or acted too late. This scenario lets you train pattern recognition + correct response under time pressure — the exact skill the rules are designed to support. RYA, Yachtmaster, deck-officer and most national exams expect you to apply COLREGs reflexively, not just recite them.

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About SkipperCheck simulators

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