Our Rules 12–18 guide explains what each steering rule says. This guide is the drill for using them: the same eight questions, in the same order, for every vessel you see — in the exam and at the helm. The order is not a mnemonic; it is the structure of the rules themselves (Rule 11 limits Rules 12–18 to vessels in sight; Rule 13 says “notwithstanding anything” in them; Rule 18 opens “except where Rules 9, 10 and 13 otherwise require”).

A six-step reasoning sequence for applying the steering and sailing rules: check risk of collision, check whether vessels are in sight of one another, check overtaking first, check whether Rules 9, 10 or 18 apply, identify the encounter rule, then act according to your give-way or stand-on role.1Is there risk of collision?Steady bearing, closing range (Rule 7). If no risk, keep watching.2Are we in sight of one another?Not in sight AND in/near restricted visibility: Rule 19.3Is either vessel overtaking?Rule 13 overrides everything else. The overtaking vessel keeps clear.4Does Rule 9, 10 or 18 change things?Narrow channel, TSS, NUC / RAM / fishing / sail vs power.5Which encounter rule applies?Sail vs sail: Rule 12. Power vs power: Rule 14 (head-on) or Rule 15 (crossing).6What does my role require?Give-way: early, substantial action (Rule 16). Stand-on: course and speed, then act if needed (Rule 17).
What to notice: The six structural questions; questions of risk (Rule 7) and adequacy of action (Rules 8 and 16) run underneath all of them. If an answer feels ambiguous, you have usually skipped a step — most often step 3.

Six-step decision sequence for applying the steering and sailing rules.

The eight questions

  1. In sight of one another? Rules 11–18 apply if the vessels can be observed visually. Rule 19 applies when they are not in sight and are navigating in or near restricted visibility; it has no stand-on role. Darkness, distance or a radar/AIS contact alone does not establish Rule 19’s conditions.
  2. Is anyone overtaking? Coming up from more than 22.5° abaft the beam — the sternlight sector. If yes: Rule 13, the overtaker keeps clear whatever she is, and stays the overtaker until finally past and clear. If in doubt, assume yes.
  3. What is each vessel? Status, not appearance: a yacht under engine (even motor-sailing) is power-driven; lights and day shapes announce fishing, NUC, RAM, constrained by draught. Most wrong answers die at this step.
  4. Does geography rule? Narrow channel (Rule 9) or TSS (Rule 10): small craft and sailing vessels must not impede vessels confined to the channel or following a lane — an early duty that comes before any pecking order.
  5. Which encounter rule? Both sailing: Rule 12 (tack, then windward). Both power-driven: Rule 14 head-on or Rule 15 crossing. Different categories: Rule 18's list.
  6. Who keeps out of the way? Name the give-way vessel and her duty: early and substantial action, avoid crossing ahead in a Rule 15 crossing if circumstances admit.
  7. What must the stand-on vessel do? Rule 17's three stages: hold course and speed; may act when the give-way vessel clearly is not; must act when collision can no longer be avoided by the give-way vessel alone — and a power-driven stand-on vessel avoids turning to port for a vessel on her own port side.
  8. Risk and adequacy. Is the bearing steady and range closing (Rule 7)? Is the action big, early, and visible (Rules 8, 16)? These two questions are always live, whatever the geometry.

Worked scenarios

Three plan-view scenarios. One: a sailing yacht close-hauled on starboard tack with a power-driven vessel approaching from her starboard bow — Rule 18, the power-driven vessel keeps out of the way, the yacht stands on. Two: two sailing yachts crossing, one on port tack and one on starboard — Rule 12, port tack keeps clear. Three: a motor yacht coming up from astern of a sailing yacht — Rule 13, the overtaking vessel keeps clear whatever she is.windsail, stbd tackpower1 · Rule 18(a): power keeps clearwindport tackstbd tack2 · Rule 12: port tack keeps clearwindsailpower, from astern3 · Rule 13: overtaker keeps clear
What to notice: Three of the five scenarios below, drawn. Work each one with the eight questions before reading the reasoning — the answers are one paragraph down.

Three plan views: sailing yacht with power vessel approaching from starboard; two sailing yachts on opposite tacks; a power vessel overtaking a sailing yacht from astern.

What would you do?1 · Close-hauled, power vessel to starboardYou are close-hauled under sail on starboard tack. A motor cruiser approaches steadily from your starboard bow; the bearing is not changing.Decide, then reveal the reasoning

In sight: yes. Overtaking: no — she is ahead of your beam. Types: you sailing, she power-driven. Channel/TSS: no. Rule: 18(a) — the power-driven vessel keeps out of the way of the sailing vessel. Note what did not matter: that she is to starboard. The “starboard side gives way” test lives in Rule 15, which is for two power-driven vessels; importing it here is the classic error. Your Rule 17 duty: hold course and speed, watch the bearing, be ready to act if she does not — and remember she may not have seen you.

What would you do?2 · The motor-sailer meets a yacht under sailYou are motor-sailing — main up, engine in gear — and converging with a yacht under sail alone on your port bow, steady bearing.Decide, then reveal the reasoning

Types first: you are power-driven (Rule 3(c): a sailing vessel is under sail with machinery not being used). So this is power vs sail: Rule 18(a), you keep out of the way, regardless of your sails and regardless of tacks. Act early and obviously (Rule 16): a substantial alteration astern of her, or slow down. Under sail alone it would have been Rule 12 and a tack comparison — which is why question 3 comes before question 5.

What would you do?3 · Two power vessels, lights at nightTwo ordinary power-driven vessels are in sight, crossing in open water with risk of collision. The other is broad on your port bow, showing a green sidelight and a white masthead light.Decide, then reveal the reasoning

Rule 15: the other vessel has you on her starboard side, so she keeps clear. You maintain course and speed subject to Rule 17: you may act when her appropriate action is not apparent, and must act when her action alone cannot avoid collision. Rule 17(c) qualifies an early turn to port for a vessel on your port side. Rule 34(d) prescribes at least five short, rapid blasts when in doubt about her intentions or sufficient action. Do not infer exact length, speed or track from one white and one green light alone.

What would you do?4 · The channel and the coasterYou are beating up a buoyed channel in your 9-metre yacht, under sail. A loaded coaster is coming up the channel astern, confined to it by her draught.Decide, then reveal the reasoning

Question 4 fires before the pecking order: Rule 9(b) — a vessel under 20 m or a sailing vessel shall not impede the passage of a vessel that can safely navigate only within the channel. Your duty is early: tack out of the fairway or hold its edge so she never has to think about you. She is also overtaking (Rule 13) — but if you rely on that and force her to act, you have already failed 9(b). In a TSS the same logic is Rule 10(j). “Sail over power” has two exceptions written into Rule 18's first line, and this is one of them.

What would you do?5 · Red over white on a dark horizonSailing at night, you make out an all-round red over an all-round white light, and below them a green sidelight, converging slowly from starboard.Decide, then reveal the reasoning

Question 3 via lights: red over white all-round is a vessel engaged in fishing (not trawling), Rule 26(c); the green sidelight means she is making way, and you see her starboard side. Rule 18(b): a sailing vessel keeps out of the way of a vessel engaged in fishing. You are give-way: alter early and substantially — and give her gear a wide margin, since it can extend far from the hull (a white all-round light or cone would mark gear over 150 m out). If the lights had been green over white (trawling) the answer would be the same; white over red (pilot) or red-white-red (RAM) would each send you back through the list.

Try it: is the bearing changing?

Encounter at 0 minutes: other vessel bears 45 degrees.you — give-wayother — stand-onBoth vessels 6 knots. Bearing measured from own vessel, north up.
Your give-way vesselYour give-way vessel
Your heading 000°. The other vessel’s compass bearing is 045°, range 14.1 illustrative units. Both are power-driven, in sight, crossing in open water with risk of collision. She is on your starboard side: you keep clear under Rule 15. She maintains course and speed subject to Rule 17.
What to notice: First hold both courses: compass bearing is steady as range closes. Then alter your give-way vessel to starboard at four minutes while the other maintains course. Watch the bearing change, but keep monitoring separation: changing bearing alone is not proof of safety.

Interactive crossing encounter: the learner’s give-way vessel alters to starboard; the other maintains course. A compass bearing readout updates with time.

Using the method in exams

  • Write the eight answers, however obvious — examiners award the reasoning, and the discipline catches the planted trick (an engine mentioned in passing, a shape you skimmed).
  • Answer in the rules' vocabulary: “keep out of the way”, “stand-on”, “early and substantial action”, “not impede” — not “has right of way”, which appears nowhere in the International rules.
  • If two rules seem to conflict, the priority order is the structure: Rule 13 over the encounter rules; Rules 9 and 10 qualify Rule 18; Rule 2 (responsibility) allows departure only when necessary to avoid immediate danger.
  • For lights questions, do question 3 from the lights first, then continue the method — our navigation-lights guide is the reference.
Check yourselfA paddleboarder is crossing ahead of your yacht under sail. Nothing about paddleboards appears in Rules 12–18. What does the method give you?Show answer

Do not invent a priority ranking. Local law may classify paddlecraft differently; the named sail/power encounter rules do not settle every case. Maintain lookout, assess risk and use prudent seamanship to avoid collision with adequate room, considering the paddleboarder’s vulnerability and manoeuvrability. Rules 2 and 5–8 remain important; being under sail is not a reason to hold a dangerous course.

Key takeaways

  • Eight questions, fixed order: in sight → overtaking → types → channel/TSS → encounter rule → give-way duty → stand-on duty → risk and adequacy.
  • Status beats appearance: engines make you power-driven; lights and shapes declare the special categories.
  • Geography (Rules 9/10) and overtaking (13) outrank the Rule 18 list — by the rules' own words.
  • Stand-on is a job with three stages, not a privilege; give-way action must be early, substantial and visible.
  • When no named rule fits, Rules 2 and 5–8 still do.