COLREG / ARPA / AIS Bridge Rule 31 🔒 Course / Premium

Rule 31 — Seaplane on the Water

NIGHT. You see on the water a vessel which is unable to comply fully with Rule 23 due to its construction.

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This scenario is part of the full library. Unlock all 54 COLREG scenarios with the Skipper Refresher Course (€99.99, lifetime + certificate) or a Premium subscription (from €29.99/mo).

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Scenario briefing

NIGHT. You see on the water a vessel which is unable to comply fully with Rule 23 due to its construction. She exhibits lights of the characteristics, positions and visibilities as closely as possible to those prescribed for a power-driven vessel but not exactly. What is she most likely to be?

Applicable COLREG rule(s)

Rule 31 — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

📸 Night recognition — 8 aspects

The same vessel rendered every 45° of aspect — bow, starboard bow, beam, quarter, stern, port quarter, beam, bow. Use this strip to learn how the lights present from each approach angle. Click any image to view full size.

Seaplane on the water viewed head-on (bow aspect) — COLREG Rule 31 night-recognition diagram — Bow

Seaplane on the water viewed from her starboard bow — COLREG Rule 31 night-recognition diagram — STBD bow

Seaplane on the water viewed from her starboard beam — COLREG Rule 31 night-recognition diagram — STBD beam

Seaplane on the water viewed from her starboard quarter — COLREG Rule 31 night-recognition diagram — STBD qtr

Seaplane on the water viewed dead astern (stern aspect) — COLREG Rule 31 night-recognition diagram — Stern

Seaplane on the water viewed from her port quarter — COLREG Rule 31 night-recognition diagram — Port qtr

Seaplane on the water viewed from her port beam — COLREG Rule 31 night-recognition diagram — Port beam

Seaplane on the water viewed from her port bow — COLREG Rule 31 night-recognition diagram — Port bow

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

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