Sail Skills - ColRegs Free Guide to ColRegs (the International Regulations for Preventing Collisions at Sea, the IRPCS or Collision Regs).  Guidance covers all aspects with animations, pictures and diagrams.  Aimed at small vessel users but suitable for professional mariners.  Especially recommended for RYA examination candidates.
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Rule 30 Anchored Vessel  Animation:  vessel 100m or more ColRegs Home>ColRegs>Lights & Shapes>Animations>Anchored>Vessel 100m or More Vessel at anchor based on a large merchant vessel 100m or more in length back to top of vessels at anchor Vessel at anchor Anchored