Nav Lights

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Navigation Lights

Vessel Navigation Lighting

Illustrated light configurations for sailing vessels and recreational craft, based on COLREGs Part C. Side profiles show the light arrangements; the sector diagram shows horizontal visibility arcs. Lights are shown from sunset to sunrise and in restricted visibility.

GREEN · 112.5°STERN (WHITE) · 135°RED112.5°Masthead (white) covers forward 225°

Light Visibility Sectors

COLREG Rule 21

Standard running lights: red (port) and green (starboard) sidelights each visible 112.5°; white sternlight 135°; white masthead light covering 225° forward. Together they light the full horizon.

Port sidelight · 112.5°Starboard sidelight · 112.5°Sternlight · 135°Masthead · 225°
Red (optional)Green (optional)SternlightBOW

Sailing Vessel Underway

COLREG Rule 25

Sidelights and a sternlight — no masthead light. May optionally show a red-over-green all-round light at the masthead to distinguish from power.

Red over green (optional all-round)SternlightPort sidelightStarboard sidelight
Tri-color (R/G/W)BOW

Tri-Color Masthead Light

COLREG Rule 25(b)

A sailing vessel under 12m (up to 20m in some jurisdictions) may show a single tri-color all-round light at the masthead combining red (port), green (starboard) and white (stern) sectors — replacing the separate sidelights and sternlight. Must NOT be used when motoring or under power.

Red · port 112.5°Green · starboard 112.5°White · stern 135°
MastheadSternlightBOW

Sailing Under Power (Motorsailing)

COLREG Rule 25(d)

A sailing vessel also being propelled by engine shows the lights of a power-driven vessel (masthead, sidelights, sternlight) — not the sailing-vessel-only set.

Masthead (white) · 225°Sternlight · 135°Port sidelightStarboard sidelight
MastheadSternlightBOW

Recreational Power-Driven Underway

COLREG Rule 23

A recreational powerboat under 12m shows a single masthead light (or an all-round white), sidelights, and a sternlight. The all-round white may replace the separate masthead and sternlight on small craft.

Masthead (white) · 225°Sternlight · 135°Port sidelightStarboard sidelight
Anchor (fwd)Anchor (aft)BOW

At Anchor

COLREG Rule 30

A vessel at anchor shows an all-round white light where best seen (vessels under 50m show one; over 50m show a forward light lower and an aft light higher). Aground shows two all-round red lights vertically in addition.

All-round white anchor light(s)Two reds = aground (add)

Reminder: These illustrations are general guidelines. Always verify exact light ranges, vertical separation, and color/arc specifications against the full COLREGs and your vessel's certification before relying on them at night.