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Part CIntermediate
Rule 25: Sailing vessels underway and vessels under oars
Sailing vessels have their own light logic; machinery use changes status and obligations.
Detailed Explanation
(a) Sailing vessel underway shows sidelights and sternlight.
(b) Under 20 m, these may be combined in one lantern at/near mast top.
(c) Optional additional all-round lights red over green at/near mast top, but not together with combined lantern of (b).
(d)(i) Sailing vessel <7 m should show prescribed lights if practicable; otherwise keep white torch/lantern ready and show in time.
(d)(ii) Vessel under oars may show sailing lights; otherwise same white light readiness.
(e) Sailing vessel also propelled by machinery shall show black cone apex down forward where best seen.
Key Points
- Sailing underway: sidelights + sternlight
- Optional: red over green all-round at masthead
- <7m: white light ready to show in time to prevent collision
- Under oars: may show sailing lights or white torch
Examples
- At night a sailing ketch shows red and green sidelights and a white sternlight. She may also display optional red-over-green all-round lights at the masthead per Rule 25(c).
- A dinghy under oars at dusk has no fixed lights. Rule 25(d)(ii) permits her to show a white light or lantern in sufficient time to prevent collision, rather than carrying full navigation lights.
Common Mistakes
- Showing masthead lights on a sailing vessel under sail alone, which are only required for power-driven vessels.
- Forgetting that a vessel under oars only needs to show a white light or lantern in time to prevent collision, not full navigation lights.
- Using the optional red-over-green all-round lights at the masthead while also showing a combined lantern, creating a confusing display.