Rule 25(e) - Sailing AND Motoring | SkipperCheck
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Rule 25(e) - Sailing AND Motoring

Daylight + NIGHT consideration. A vessel proceeds under SAIL and at the same time is being propelled by MACHINERY.

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Scenario briefing

Daylight + NIGHT consideration. A vessel proceeds under SAIL and at the same time is being propelled by MACHINERY. What signal identifies this dual propulsion? (Rule 25(e))

Applicable COLREG rule(s)

Rule 25(e) — referenced in this scenario. Practising this scenario reinforces correct application under realistic time pressure.

📸 Night recognition — 8 aspects

The same vessel rendered every 45° of aspect — bow, starboard bow, beam, quarter, stern, port quarter, beam, bow. Use this strip to learn how the lights present from each approach angle. Click any image to view full size.

Key teaching points

  • Rule 25(e): a sailing vessel propelled by machinery AND sail shall exhibit forward where it can best be seen a conical shape, apex downward.
  • By night the same vessel shows the lights of a power-driven vessel (Rule 23) — masthead, sidelights, sternlight.
  • The Rule 18(a)(iv) priority over power-driven vessels DOES NOT apply when under sail + power.
  • This is a Rule 25(e) duty that yacht crews routinely forget — the conical shape is mandatory in daylight.

Common mistakes to avoid

  • Sailing with engine running and not hoisting the conical shape — common breach in pleasure-craft fleets.
  • Claiming Rule 18(a)(iv) priority while motor-sailing — courts have ruled against vessels that did this.

Why it matters

A sailing vessel proceeding under sail AND machinery is, under Rule 25(e), a power-driven vessel for COLREG purposes — and the Rule 18(a)(iv) priority for sailing vessels evaporates. The conical-day-shape requirement exists precisely to prevent the ambiguity from confusing nearby traffic.

Exam relevance

Rule 25(e) "motor-sailing" duty is a popular probe in Yachtmaster Coastal/Offshore and ICC orals.

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