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25

Sailing Vessels Underway and Vessels Under Oars

Sailing vessels show sidelights and sternlight. May optionally show red over green all-round lights at the masthead.

Rule 25 covers lights for sailing vessels and vessels under oars.

a
A sailing vessel underway shall exhibit sidelights and a sternlight.
b
In a sailing vessel of less than 20 metres, the sidelights and sternlight may be combined in one lantern at or near the top of the mast.
c
A sailing vessel underway may, in addition to sidelights and sternlight, exhibit at or near the top of the mast two all-round lights in a vertical line, the upper being red and the lower green (optional).
d
A vessel under oars may exhibit the lights for sailing vessels or have ready at hand an electric torch or lighted lantern showing a white light to prevent collision.

Recognition Sequence

1

Classify the vessel state first: underway, making way, stopped, at anchor, aground, towing, fishing, pilotage or special condition.

2

Read special lights vertically from top to bottom before using sidelights and sternlight to confirm aspect.

3

Then confirm the answer with the day shape, vessel length and any extra signal such as towing lights, deck illumination or a cylinder.

Exam Focus

1

Avoid identifying a vessel from one colour alone. Many mistakes come from spotting a red light and guessing before checking the full pattern.

2

If the question mentions 'making way', 'underway but stopped', 'at anchor' or 'aground', that wording usually determines which extra lights or shapes appear.

Key Takeaways

1

Sailing vessels show sidelights and sternlight only (no masthead light)

2

Optional red-over-green all-round lights at masthead

3

Small sailing vessels may combine lights in one lantern

4

Vessels under oars need at minimum a white light ready

Common Mistakes

Expecting a masthead light on a sailing vessel

Confusing optional red/green masthead lights with required lights

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