What to show, and when
| When you're | Show |
|---|---|
| Sailing, any length | Sidelights and a sternlight. Optional all-round red over green at the masthead. |
| Sailing, under 20m | As above, or the sidelights and sternlight combined in one tricolour lantern at or near the masthead. Never the tricolour together with the red over green. |
| Sailing, under 7m | Sidelights and sternlight if practicable. If not, have a white torch or lantern ready to show in time to prevent a collision. |
| Under engine (including motor-sailing), under 50m | A white masthead light, sidelights and a sternlight. Not the tricolour. |
| Under engine, under 12m | May show an all-round white light and sidelights instead. |
| Under engine, under 7m with a top speed of 7 knots or less | May show just an all-round white light, with sidelights if practicable. |
| At anchor, under 50m | An all-round white light where it can best be seen. Under 7m, not needed away from channels, fairways, anchorages and where vessels normally navigate. |
The tricolour and the steaming light
The tricolour is popular on yachts because one bulb at the top of the mast is easy to see over waves and uses little power. But it's only for sailing. The moment the engine is running and driving you, you're a power-driven vessel. Switch the tricolour off, and switch on the sidelights and sternlight with the white masthead light, often called the steaming light.
By day
Under sail and engine together, show a cone, point down, forward where it can best be seen. At anchor, show one black ball forward. For every other vessel's lights and shapes, see navigation lights and day shapes.
Check before dark
- Test every light before you leave, including the anchor light and the steaming light.
- Carry spare bulbs or a spare LED unit, and a powerful torch.
- Know which switch is which by feel, so you can change lights quickly in the dark.