Most people meet the Navigation Rules as a list of who has right of way, and that framing causes the accidents. The Rules never grant a right of way. They assign two *roles* — one vessel keeps out of the way, the other holds its course so the first can predict it — and both roles come with duties, including the duty to break the pattern when the plan is failing. Everything else is machinery for making those roles visible: lights say what a vessel is and what it is doing, sound signals say what it intends, and buoys say where the water is. Read this in that order — roles first, then the signalling that supports them — and the individual rules stop needing memorisation.
Each chapter opens with the short version. Tap one to read the detail.
What the Rules are, who they bind, and the rule that overrides the rest
~2 min
The Rules apply to every vessel, from a kayak to a container ship, and two sets exist — International offshore and Inland inside the demarcation lines. Rule 2 sits above all of it: no rule excuses you from the ordinary precautions a seaman would take.
Lookout, safe speed, and how risk of collision is actually judged
~2 min
Four duties apply at all times and in every condition: keep a proper lookout, proceed at a safe speed, determine whether risk of collision exists, and take action that is early, substantial and obvious. Most collisions fail at the first two.
The three geometries, and why "give-way" is a job description
~2 min
Every power-driven encounter reduces to head-on, crossing, or overtaking. Each assigns one vessel to keep out of the way and the other to hold course and speed — and the stand-on vessel's duty is an obligation to be predictable, not a privilege.
Rule 18's pecking order, and its two big qualifications
~2 min
When vessels of different types meet, a ranking decides who keeps clear: not under command, restricted in ability to manoeuvre, constrained by draught, fishing, sailing, then power-driven. The ranking is real, but it does not survive a narrow channel or an overtaking situation.
Narrow channels, traffic schemes, and what fog actually changes
~2 min
In a narrow channel, keep to the starboard side and do not impede a vessel that can only navigate there. In restricted visibility, the give-way and stand-on roles do not exist at all — that is the single most important thing fog changes.
How to read a light: arcs, ranges, and when they are required
~2 min
Navigation lights are a language with fixed vocabulary. Each light has a defined colour, a defined arc of visibility measured in degrees, and a minimum range set by vessel length — so the lights you can see tell you the aspect you are viewing from.
Reading a vessel's job from its lights
~2 min
Beyond the basic set, extra lights say what a vessel *is doing* — towing, fishing, dredging, restricted, aground, at anchor. These are the lights that tell you where the vessel sits in the Rule 18 hierarchy before it is close enough to see anything else.
Sound signals say intention, not warning
~2 min
Short blasts announce manoeuvres. In International waters they state what you are doing; in Inland waters they propose it and require agreement. That difference — action versus proposal — is the most consequential divergence between the two rule sets.
Buoyage: the lateral system and what it assumes
~2 min
United States buoyage follows the International Association of Marine Aids to Navigation and Lighthouse Authorities Region B convention: red to the right when returning from sea. Everything else in the system is a modifier on that one rule, and it is the opposite of the convention used across much of the world.
Bridges, regulated areas, and the rules that are local
~2 min
Beyond the Navigation Rules sit federal regulations for specific waters: bridge signals and clearances, safety and security zones, speed-restricted areas and vessel traffic services. These are local by nature, so the operative skill is knowing they exist and where to look.
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