COLREG / ARPA / AIS Bridge
Rule 25(a)
Rule 25(c)
🔒 Course / Premium
Rule 25 — Sailing Vessel Underway Lights
NIGHT. You see an approaching vessel showing: red & green sidelights; white sternlight (she is heading generally toward you and slightly past); NO...
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Scenario briefing
NIGHT. You see an approaching vessel showing: red & green sidelights; white sternlight (she is heading generally toward you and slightly past); NO masthead light at all. Optionally: two all-round lights at the top of the mast RED OVER GREEN. What type of vessel is this?
Applicable COLREG rule(s)
Rule 25(a) — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.
Rule 25(c) — 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, STCW and most national exams expect you to apply COLREGs reflexively, not just recite them.
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About SkipperCheck simulators
SkipperCheck offers two browser-based maritime training simulators:
- ARPA · AIS · COLREG Bridge Simulator — 54 scenarios covering Rules 2, 5–10, 12–19, 23–30, 34 and 35.
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