Navigation lights and shapes: who is that in the dark

The base set every other configuration is counted from: two masthead lights in line (the after one higher), sidelights and a sternlight.

Set

Forward masthead, after masthead higher, green to starboard, red to port, white sternlight.

Tell

Two white mastheads: the forward one lower, the after one higher. Bow-on they are almost in one vertical line, and the more her aspect opens the wider they separate horizontally. Two whites strictly in a vertical line on one mast are the mark of towing, not of size.

In fog

One prolonged blast at intervals of not more than 2 minutes. If stopped: two prolonged blasts.

Gives way

To vessels not under command, restricted in ability to manoeuvre, engaged in fishing, and sailing vessels.

Range

Masthead 6 miles, sidelights and sternlight 3 miles.

The same, but the second masthead light is optional: usually you see one white masthead, sidelights and a sternlight.

Set

Masthead, sidelights, sternlight. Second masthead optional.

Tell

One white light high up plus a coloured sidelight: a medium power-driven vessel.

In fog

One prolonged blast every 2 minutes at most.

Range

Masthead 5 miles, or 3 miles if she is under 20 m.

Instead of masthead and sternlight she may show one all-round white light plus sidelights.

Set

All-round white (visible from every direction), green and red sidelights.

Tell

An all-round white with no second white: a small vessel. From astern you see the white only, no colours.

Offset

On a vessel under 12 m the white light may be off the centreline if fitting it on the centreline is impracticable.

Range

White 2 miles, sidelights 1 mile: she can be spotted very late.

One all-round white light is enough. Sidelights are shown if practicable.

Set

All-round white. Sidelights if practicable.

Tell

A lone white light with no colours: neither her course nor her aspect can be read, so leave a wide margin.

In fog

She must make some efficient sound signal at intervals of not more than 2 minutes.

The normal power-driven set plus an all-round flashing yellow light.

Set

Masthead lights, sidelights, sternlight, all-round flashing yellow.

Tell

A flashing yellow light: her speed can be very high and closing is fast.

Flash

120 flashes per minute or more.

The normal power-driven set plus a high-intensity all-round flashing red light.

Set

Masthead lights, sidelights, sternlight, all-round flashing red.

Tell

A bright flashing red: a WIG craft. Taking off and in flight she keeps well clear of all vessels.

On the water

On the surface she is an ordinary power-driven vessel.

Sidelights and a sternlight only. No masthead light: that is the giveaway of a sailing vessel.

Set

Green to starboard, red to port, white sternlight.

Tell

A coloured sidelight with no white light above it: a sailing vessel. A power-driven vessel always carries a masthead light.

In fog

One prolonged and two short blasts every 2 minutes at most.

Gives way

To vessels not under command, restricted in ability to manoeuvre and engaged in fishing. Power-driven vessels give way to her.

The sidelights and sternlight may be combined in one lantern at or near the top of the mast.

Set

One lantern at the masthead: green sector to starboard, red to port, white astern.

Tell

All the lights in a single point high on the mast instead of spread along the hull.

Limit

With this lantern the optional red-over-green lights must not be shown.

Optionally, at or near the masthead, an all-round red above an all-round green.

Set

Sidelights, sternlight, plus red over green at the masthead.

Tell

Red over green: a sailing vessel. Do not confuse with white over red (pilot) or red over white (fishing).

Limit

Not to be shown together with the combined lantern of paragraph (b).

By the rules she is a power-driven vessel: the lights of rule 23, and by day a cone with the point down.

Set

Masthead, sidelights, sternlight. By day a cone point down, forward where best seen.

Why

Without the cone everyone reads her as a sailing vessel with right of way, while her duties are the opposite.

In fog

As a power-driven vessel: one prolonged blast, or two if stopped.

She may show the lights for sailing vessels. If she does not, she must keep an electric torch or lighted lantern showing a white light ready and show it in time to prevent collision.

Set

White torch or lantern, shown in good time.

Tell

A single low light close to the water: a rowing boat or a very small sailing vessel.

Practice

The light must be shown early, not when the vessel is already close.

Two masthead lights in a vertical line instead of one, plus sidelights, sternlight and a yellow towing light above the sternlight.

Set

Two masthead lights in a vertical line, sidelights, white sternlight, yellow towing light directly above it.

Tell

From astern you see two lights in a column: yellow on top, white below. There is something on a wire behind her.

Danger

A tow wire runs between the towing and towed vessel. Never pass between them.

In fog

One prolonged and two short blasts. The tow answers with one prolonged and three short.

From 50 m

From 50 m a towing vessel also carries the second masthead light of rule 23 (a) (ii), so there is one white light more.

Three masthead lights in a vertical line and a diamond shape by day. The length of tow is measured from the stern of the towing vessel to the after end of the tow.

Set

Three masthead lights in a vertical line, sidelights, sternlight, yellow towing light. Diamond by day.

Tell

Three white lights in a column: a very long tow, give it a wide berth.

Shape

The diamond is shown by both the towing and the towed vessel.

From 50 m

From 50 m one more masthead light is added under rule 23 (a) (ii).

Two masthead lights in a vertical line, sidelights and a sternlight. No yellow towing light: that is what separates her from towing on a wire.

Set

Two masthead lights, sidelights, sternlight. No yellow towing light.

Tell

Two whites in a column but no yellow from astern: the unit is rigid or alongside, no wire between.

Composite unit

If the pushing and pushed vessels are rigidly connected they count as one power-driven vessel and show the lights of rule 23.

From 50 m

From 50 m one more masthead light is added under rule 23 (a) (ii).

Sidelights and a sternlight, no masthead lights. A diamond by day if the tow is longer than 200 m.

Set

Green and red sidelights, white sternlight.

Tell

Sidelights with no masthead light, just like a sailing vessel. Look ahead of her for a towing vessel with two whites in a column.

In fog

One prolonged and three short blasts, right after the towing vessel's signal, if she is manned.

A vessel being pushed ahead shows sidelights at the forward end. A vessel towed alongside shows sidelights forward and a sternlight.

Set

Sidelights at the forward end. A sternlight only when towed alongside.

Rule

Any number of vessels being towed alongside or pushed in a group are lighted as one vessel.

When the tow leaves the towing and towed vessel almost no room to deviate from their course, the towing lights are joined by all-round red, white, red.

Set

The towing lights of 24 (a) plus all-round red, white, red. Ball, diamond, ball by day.

Tell

Two whites in a column next to three all-round lights: a tug that physically cannot turn.

Priority

Everyone gives way to her except a vessel not under command.

All-round white lights at the ends: from 25 m in breadth two more at the sides, and over 100 m in length enough lights so that the gap between them is never more than 100 m.

Set

All-round whites at the forward and after ends (a dracone need not show the forward one), two more at the outer edges from 25 m in breadth, and over 100 m in length spaced so the gap never exceeds 100 m.

Tell

A chain of low white lights just above the water with no sidelights and no masthead light: an almost invisible object under tow.

Shape

A diamond at the after end of the last object, plus another one forward if the tow exceeds 200 m.

An all-round green over an all-round white. Making way through the water she adds sidelights and a sternlight. From 50 m she adds a masthead light abaft and higher than the green.

Set

Green over white all-round, masthead light (from 50 m), sidelights, sternlight.

Tell

Green over white: she is dragging a trawl or dredge. Mnemonic: green means she is going.

In fog

One prolonged and two short blasts.

Priority

She gives way to vessels not under command and restricted in ability to manoeuvre. Power-driven and sailing vessels give way to her.

Only the all-round green over white: no sidelights and no sternlight, because she has no way on.

Set

Green over white all-round.

Tell

Green over white with no sidelights: gear is in the water and she is not making way.

By day

Two cones with their apexes together.

An all-round red over an all-round white: nets, lines, long-lines. Making way she adds sidelights and a sternlight.

Set

Red over white all-round, plus sidelights and sternlight when making way.

Tell

Red over white: she is fishing with static gear. Do not confuse with white over red (pilot).

In fog

One prolonged and two short blasts, at anchor as well.

An extra all-round white light, or a cone point up by day, in the direction of the outlying gear.

Set

Red over white, plus an all-round white towards the gear.

Tell

A white light offset from the fishing vessel: the gear is there, pass on the other side.

Distance

The rule applies once the gear extends more than 150 m horizontally.

Two all-round red lights in a vertical line. Two balls by day. This is a breakdown: she cannot manoeuvre.

Set

Two all-round reds.

Tell

Two reds in a column and no whites at all: not under command and not making way.

In fog

One prolonged and two short blasts.

Priority

Every vessel gives way to her, without exception.

Sidelights and a sternlight are added to the two all-round reds. Masthead lights are not shown, even while she carries her way.

Set

Two all-round reds, sidelights, sternlight. No masthead lights.

Tell

This is the key fork: a masthead light next to two reds means she is not a breakdown but restricted in ability to manoeuvre, and there the lights are red, white, red.

Causes

Steering gear failure, loss of propulsion, engine breakdown.

All-round red, white, red in a vertical line. With way on she adds masthead lights, sidelights and a sternlight.

Set

All-round red, white, red, masthead lights, sidelights, sternlight. Ball, diamond, ball by day.

Tell

The white in the middle of two reds means work, not a breakdown: cable laying, replenishment underway, launching aircraft, mine clearance, a heavy tow.

In fog

One prolonged and two short blasts.

Priority

Everyone gives way to her except a vessel not under command.

All-round red, white, red plus the anchor lights of rule 30.

Set

All-round red, white, red and the all-round white anchor lights.

Tell

Three all-round lights together with anchor whites: the work is being done from anchor, she is not going anywhere.

In fog

One prolonged and two short blasts instead of the bell.

Two all-round reds mark the side where the obstruction is, two all-round greens the side on which another vessel may pass.

Set

Red, white, red plus two reds on one side and two greens on the other.

How to read

Go where the two greens are. On the side of the two reds there is pipeline, anchors or the dredger's gear.

By day

Ball, diamond, ball plus two balls on the obstructed side and two diamonds on the clear side.

At anchor

These lights replace the anchor lights.

When her size makes the full display of paragraph (d) impracticable: all-round red, white, red and a rigid replica of flag «A» not less than 1 m high.

Set

Three all-round lights and a rigid flag «A» visible all round.

Meaning

There are people in the water. Passing close at speed is dangerous: slow right down and leave room.

Exception

Vessels under 12 m are exempt from rule 27, but not when engaged in diving operations.

Three all-round green lights or three balls in addition to the lights for a power-driven vessel: one near the foremast head, two at the fore yardarm ends.

Set

Power-driven vessel's lights plus three all-round greens in a triangle.

Meaning

It is dangerous to approach within 1000 metres.

By day

Three balls in the same positions.

In addition to the lights of a power-driven vessel she may show three all-round red lights in a vertical line, or a cylinder by day.

Set

Masthead lights, sidelights, sternlight plus three all-round reds. Cylinder by day.

Tell

Three reds in a column together with masthead lights: depth will not let her turn. Two reds without masthead lights would mean a breakdown.

Priority

Every vessel except those not under command or restricted in ability to manoeuvre must avoid impeding her safe passage.

In fog

One prolonged and two short blasts.

An all-round white over an all-round red at or near the masthead. Underway she adds sidelights and a sternlight.

Set

White over red at the masthead, sidelights, sternlight.

Tell

White on top, red below. Mnemonic: white over red, pilot ahead. The reverse order, red over white, means fishing.

In fog

As a power-driven vessel, and she may add four short blasts as an identity signal.

Off duty

A pilot vessel not on duty shows the ordinary lights for a vessel of her length.

White over red plus the anchor lights of rule 30.

Set

White over red and the all-round white anchor lights.

Tell

A white-red pair with no sidelights: a pilot boat waiting at anchor.

An all-round white light in the fore part and a second all-round white at or near the stern, lower than the first. A ball forward by day.

Set

Two all-round whites: forward higher, aft lower. No sidelights and no sternlight.

Tell

Two whites, no colours, no movement: she is stopped. The height difference shows where her bow is.

Decks

A vessel of 100 m or more must also light her decks with available working lights.

In fog

Rapid ringing of the bell for about 5 seconds at intervals of not more than a minute. From 100 m: bell forward, gong aft.

She may show one all-round white light where it can best be seen.

Set

One all-round white. Ball by day.

Exception

A vessel under 7 m at anchor, when not in or near a narrow channel, fairway, anchorage or where other vessels normally navigate, need not show it.

Risk

A lone white light is easily taken for a small vessel underway: approach carefully.

The anchor lights plus two all-round red lights in a vertical line. Three balls in a vertical line by day.

Set

All-round white anchor lights and two all-round reds.

Tell

Reds together with anchor whites: she is not merely stopped, she is aground. There is shallow water right there.

In fog

The bell as at anchor, plus three separate distinct strokes before and after each rapid ringing.

Exception

A vessel of less than 12 m aground need not show these lights and shapes.