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COLREGs Trainer

Recognition, rules, and decision practice for the COLREGs — free, aligned to the MCA syllabuses, not MCA-approved.

Independent preparatory study aligned to the MCA OOW (Yachts <3000 GT) oral examination syllabus. Not an MCA-approved course and confers no credit toward a Certificate of Competency.

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Rules

The Rules, verbatim

Rules 1–41 and Annexes I–IV, complete and word-for-word — MSN 1781; MSN 1781 (M+F): Rules text stated on the document as amended through IMO Res A.

Contains public sector information reproduced under the Open Government Licence v3.0.

Recognition decks

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Navigation lights78 cards

Recognise any vessel by her lights — night views from every informative aspect, straight from Rules 21–30.

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Day shapes9 cards

The shape-carrying statuses — balls, cones, cylinders and diamonds from Rules 24–30.

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Sound signals20 cards

Manoeuvring, warning and restricted-visibility signals — Rules 34–37, patterns rendered as blast notation.

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Distress signals16 cards

Annex IV, item by item and verbatim — the current text including DSC and EPIRB alerts.

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Morse code36 cards

A–Z and 0–9 per the ITU-R M.1677 international Morse alphabet. Runs pattern→character; reversible in the player.

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IALA buoyage18 cards

The IALA Maritime Buoyage System — laterals in both regions, preferred channels, cardinals, and the rest of the family. Original teaching content; system facts verified against IALA/NGA/Trinity House guidance.

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Encounter simulator

Ten live encounters at 30×, paused at the decision point — choose your action as the officer of the watch and get an examiner's debrief.