COLREGs: A Practical Guide for Yacht Crew and Captains

Most maritime collisions involve a violation of COLREGs — an inadequate lookout, excessive speed in poor visibility, failure to take action in sufficient time, or misidentification of the navigating situation. MAIB (UK Marine Accident Investigation Branch) and equivalent bodies cite COLREGs violations as a primary factor in the majority of collision cases they investigate. For yacht crew, STCW assessment and RYA Yachtmaster examinations test COLREGs knowledge and application directly.

The most common confusion: sailors assuming that under sail always confers right of way. Rule 18 establishes a hierarchy: power-driven vessels give way to sailing vessels and fishing vessels engaged in fishing. But sailing vessels give way to vessels not under command (NUC), vessels restricted in ability to manoeuvre (RAM), and fishing vessels. A sailing vessel under engine (motor-sailing) is a power-driven vessel for COLREGs purposes and must show a steaming light. Understanding the full Rule 18 hierarchy prevents dangerous assumptions.

Incorrect navigation lights are a PSC deficiency and a collision hazard. The most common errors on yachts: sailing with the steaming light on while under sail only; using a combined tricolour light while motoring (only valid under sail); incorrect light ranges for vessel length; and burned-out lights not replaced. All navigation lights should be tested at the start of every night watch and checked as part of the PMS weekly inspection routine.

Sound signals are required in restricted visibility and when manoeuvring in sight of another vessel. Many yacht crew are unfamiliar with the restricted visibility signals — the single prolonged blast every two minutes required from a power-driven vessel making way. In fog, this signal is critical: it identifies your vessel type and status to vessels that may hear you before seeing you on radar. A vessel at anchor in fog rings a bell for 5 seconds each minute. An air horn must be available on deck and functional at all times.

TSS entry is common for yachts transiting major shipping routes: the English Channel, Dover Strait, Strait of Gibraltar, Strait of Messina, and major port approaches. The rules are often misunderstood: yachts may use the inshore traffic zone when available; yachts are permitted to cross TSS lanes but must cross at right angles to the traffic flow and not impede vessels in the lane. Radar and AIS monitoring are essential in TSS areas — traffic density and vessel speeds create rapidly changing situations.