Navigation Lights, Day Shapes and Sound Signals Quiz
Test yourself on the lights a vessel shows at night, the shapes she hoists by day and the signals she sounds, with every answer explained from the COLREGs. Free, no sign-up.
Question 1 of 28
New to the rules? Start with our guide to boat navigation lights.
Lights
At night you see these lights dead ahead. What is coming towards you?
How the Quiz Works
Pick a topic, answer, and learn from each rule
Choose a topic
Take all 28 questions, or only lights, day shapes or sound signals.
Answer each question
Read the lights, the shapes or the blasts, and pick what they mean. The answer and the reason show at once.
Read the rule
Each answer links to its rule in the COLREGs course, and your score ends with the rules worth reading again.
What the Quiz Covers
COLREGs Part C, lights and shapes, and Part D, sound signals
Lights at night
Power-driven and sailing vessels, towing, fishing, pilots, not under command, restricted, constrained by draught, at anchor and aground.
Day shapes
Balls, cones, a cylinder and a diamond: what each combination means and the lights that match it at night.
Sound signals
Manoeuvring and warning signals in sight of another vessel, overtaking in a narrow channel, and fog signals.
Every answer explained
Each question names its rule and links to it, so a wrong answer becomes the next thing you learn.
Who Takes the Quiz
Cadets and deck officers
Revise Rules 23 to 35 before a COLREGs exam or an oral, one topic at a time.
Boaters and yacht skippers
Check that you can read a vessel's lights at night before you go out after sunset.
Instructors
Set the quiz as a quick test for a class, with the rules linked for anyone who gets one wrong.
Frequently Asked Questions
Everything you need to know about the Navigation Lights Quiz.
What are the colours of navigation lights?
Sidelights are green on the starboard (right) side and red on the port (left) side. Masthead lights, sternlights and anchor lights are white, and the towing light above the sternlight is yellow. All-round lights in other colours, such as two reds or red, white, red, signal a vessel's status.
How do I tell which way a vessel is heading at night?
If you see her green and red sidelights together, she is heading straight at you. Only green means you see her starboard side, and only red her port side. On a vessel of 50 metres or more, the after masthead light is higher than the forward one, so the two white lights also show her heading.
What are day shapes?
Day shapes are black balls, cones, cylinders and diamonds hoisted where they can best be seen, to show by day what lights show at night. One ball means at anchor, two balls not under command, three balls aground, and a cylinder constrained by her draught.
How long is a short blast and a prolonged blast?
Under Rule 32, a short blast lasts about one second and a prolonged blast four to six seconds.
What does five short blasts mean?
At least five short and rapid blasts is the doubt or danger signal under Rule 34(d): the vessel sounding it does not understand your intentions, or doubts that you are doing enough to avoid a collision.
Where can I learn the rules behind the answers?
Every answer links to its rule in the free COLREGs course on this site. Our guide to boat navigation lights explains the colours, arcs and positions in more depth.
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