Rules of the Road

Who gives way and why — every steering and sailing rule in plain language, with a diagram of the situation and the official USCG text one tap away.

Encounter trainer

Read the geometry, choose your first action, and get the governing rule immediately.

Who gives way?

The five encounters every exam tests — jump straight to the one you need.

Sail vs sail

Rule 12

Overtaking

Rule 13

Head-on

Rule 14

Crossing

Rule 15

Different types

Rule 18

Conduct in any visibility

Rules 4–10 — look-out, safe speed, risk, avoiding action, channels, and schemes. These never switch off.

Rule 4Application — any visibilityLook-out, safe speed, and collision-risk rules never switch off.Rule 5Look-outEyes and ears, always — electronics assist the look-out, they never replace it.Rule 6Safe speedSafe speed is the speed you can stop within — set by conditions, not by your schedule.Rule 7Risk of collisionSteady bearing + closing range = collision course. If in doubt, assume risk exists.Rule 8Action to avoid collisionAct early, act big — one obvious alteration beats a string of small ones.Rule 9Narrow channelsKeep to the starboard edge of the channel; small craft and sailboats must not impede channel-bound ships.Rule 10Traffic separation schemesGo with the lane, keep clear of the zone, and cross at right angles to the flow.

In sight of one another

Rules 11–18 — the give-way and stand-on system. Only when you can actually see each other.

Rule 11Application — in sight of one anotherGive-way and stand-on exist only when you can see each other — on radar in fog, Rule 19 applies instead.Rule 12Sailing vesselsPort tack gives way; same tack — windward gives way; port tack and unsure — keep clear.Rule 13OvertakingComing up from more than 22.5° abaft her beam? You are overtaking — keep clear, whatever you are, until past and clear.Rule 14Head-on situationMeeting head-on: both give way — alter to starboard, pass port to port.Rule 15Crossing situationSee a power-driven vessel crossing on your starboard side? You give way — and don't cross ahead of her.Rule 16Action by give-way vesselGive way early, obviously, and generously — leave no doubt.Rule 17Action by stand-on vesselHold course and speed — until the give-way vessel clearly isn't acting (may act), or collision is imminent (must act).Rule 18Responsibilities between vesselsNUC → RAM → CBD → Fishing → Sailing → Power: give way to everything above you — unless Rule 9, 10, or 13 applies.

Restricted visibility

Rule 19 — fog, mist, heavy rain. Nobody stands on.

Rule 19Conduct in restricted visibilityIn fog nobody stands on. Slow down, and never turn to port for a vessel forward of the beam.

General

Rules 1–3 — responsibility, and the definitions everything else is built on.

Rule 2ResponsibilityHaving right of way is no defense — your first duty is always to avoid the collision.Rule 3General definitions“Underway” means not anchored, moored, or aground — a vessel can be underway while dead in the water.

Lights & shapes

Open Lights & Shapes

Rules 20–31 — summarized here; every configuration is covered in rotatable 3D in the Lights topic.

Rules 20–31Lights & shapes — overviewLights tell you what a vessel is, what she's doing, and which way she's heading — learn them in 3D on the Lights pages.

Sound & light signals

Open Sound Signals

Rules 32–37 — summarized here; every signal is playable in the Sounds topic.

Rules 32–37Sound & light signals — overviewOne short = port-to-port pass, two short = starboard-to-starboard — but International signals announce action while Inland signals propose it.