TheoryUSCG OUPV / Master Captain Licence
Practice Test
120 USCG-style questions on COLREGS, navigation rules, deck safety and seamanship so you pass the OUPV or Master exam.
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USCG OUPV / Master Captain Licence exam — full Q&A walkthrough
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30 free USCG OUPV / Master Captain Licence questions
Sampled across every topic area — not just the first page. Try them as a quiz or flip them as flashcards.
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Navigation Lights (COLREGS)
What is the arc of visibility for sidelights?
Correct — C. Sidelights (red to port, green to starboard) each cover 112.5 degrees from dead ahead. -
Navigation Lights (COLREGS)
A power-driven vessel underway less than 50 meters in length must exhibit how many masthead lights?
Correct — B. A power-driven vessel under 50m may show one masthead light (Rule 23(a)). -
Navigation Lights (COLREGS)
A sailing vessel underway must show which lights?
Correct — D. A sailing vessel shows sidelights and a stern light (Rule 25). No masthead light when under sail only. -
Navigation Lights (COLREGS)
A vessel not under command shows which lights?
Correct — C. A vessel not under command shows two all-round red lights in a vertical line (Rule 27(a)). -
Navigation Lights (COLREGS)
What lights does a vessel constrained by her draft display?
Correct — B. A vessel constrained by draft shows three all-round red lights in a vertical line (Rule 28). -
Navigation Lights (COLREGS)
What color is the stern light?
Correct — D. The stern light is a white light visible over 135 degrees centered on the stern (Rule 21(c)). -
Navigation Lights (COLREGS)
A vessel engaged in towing with the tow exceeding 200 meters shows which lights?
Correct — B. When the tow exceeds 200m, the towing vessel shows three masthead lights forward in a vertical line (Rule 24(a)). -
Navigation Lights (COLREGS)
What color are the lights for a vessel restricted in her ability to maneuver when not making way?
Correct — C. A vessel restricted in ability to maneuver shows an all-round red, white, and red (top to bottom) in vertical line (Rule 27(b)). -
Navigation Lights (COLREGS)
What is the minimum visibility range for the masthead light on a vessel 50 meters or more in length?
Correct — D. Masthead lights on vessels 50m or more must be visible at 6 miles (Annex I). -
Navigation Lights (COLREGS)
A vessel engaged in fishing (other than trawling) underway shows which lights?
Correct — B. A fishing vessel (non-trawling) shows all-round green over white, plus sidelights and stern when making way (Rule 26(b)). -
Navigation Lights (COLREGS)
A trawler when trawling shows which all-round lights?
Correct — C. A vessel trawling shows all-round green over all-round white lights (Rule 26(b)(i)). -
Navigation Lights (COLREGS)
A power-driven vessel underway greater than 50 meters in length must show how many masthead lights?
Correct — D. A power-driven vessel over 50m must show two masthead lights, the aft one higher than the forward (Rule 23(a)). -
Navigation Lights (COLREGS)
What is the arc of the stern light?
Correct — B. The stern light covers 135 degrees, centered on the vessel's stern (Rule 21(c)). -
Navigation Lights (COLREGS)
Which side is the green sidelight shown on?
Correct — C. The green sidelight is on the starboard (right) side of the vessel (Rule 21(b)). -
Navigation Lights (COLREGS)
A vessel less than 7 meters in length whose maximum speed does not exceed 7 knots may show only which light?
Correct — D. A vessel under 7m with max speed under 7 knots need only show a white all-round light, or at minimum have a flashlight ready (Rule 23(d)). -
Navigation Lights (COLREGS)
A power-driven vessel making way shows sidelights with what combined sector?
Correct — B. Port and starboard sidelights each cover 112.5 degrees for a total combined arc of 225 degrees from ahead. -
Navigation Lights (COLREGS)
A sailing vessel under 20 meters may combine sidelights and stern light into what?
Correct — C. A sailing vessel under 20m may use a tricolor lantern at or near the top of the mast (Rule 25(b)). -
Navigation Lights (COLREGS)
What is the color of the masthead light?
Correct — D. The masthead light (also called steaming light) is white, visible over 225 degrees (Rule 21(a)). -
Navigation Lights (COLREGS)
A sailing vessel also using its engine (motoring) must show which additional light or indication?
Correct — B. A sailing vessel under power shows a cone point downward during daylight, and at night must show masthead light (Rule 25(e)). -
Shapes (COLREGS)
What shape does a vessel at anchor display by day?
Correct — C. A vessel at anchor displays a black ball shape by day (Rule 30(a)). -
Shapes (COLREGS)
A vessel not under command shows which shapes by day?
Correct — D. A vessel not under command shows two black balls in a vertical line by day (Rule 27(a)). -
Shapes (COLREGS)
What shape does a vessel constrained by her draft show by day?
Correct — B. A vessel constrained by draft displays a cylinder by day (Rule 28). -
Shapes (COLREGS)
A vessel aground shows which shapes by day?
Correct — C. A vessel aground shows three balls in a vertical line by day (Rule 30(d)). -
Shapes (COLREGS)
A vessel restricted in ability to maneuver (RAM) shows which shapes by day?
Correct — D. A RAM vessel shows ball-diamond-ball (top to bottom) in a vertical line by day (Rule 27(b)). -
Shapes (COLREGS)
A minesweeper or vessel engaged in minesweeping shows which shapes?
Correct — B. Minesweepers show three black balls — one at the foremast head and one at each end of the foreyard (Rule 27(f)). -
Shapes (COLREGS)
What minimum diameter must a day shape (ball) be for vessels over 20 meters?
Correct — C. Day shapes for vessels over 20m must have a minimum dimension of 0.6 m (Annex I). -
Shapes (COLREGS)
Which vessel displays a basket or other appropriate shape to indicate it is engaged in fishing?
Correct — D. A vessel with outlying gear extending more than 150m horizontally shows a basket or appropriate shape in the direction of the gear (Rule 26(c)(i)). -
Shapes (COLREGS)
The shapes in the Rules of the Road are what color?
Correct — B. All day shapes prescribed by the Collision Regulations are black (Rule 20). -
Shapes (COLREGS)
A vessel proceeding under sail when also being propelled by machinery shall exhibit where practicable, in addition to the sidelights:
Correct — C. A sailing vessel using its engine in addition to sail shows a cone, apex downward, forward where visible (Rule 25(e)). -
Shapes (COLREGS)
A vessel engaged in underwater operations shows which shapes by day?
Correct — D. A vessel in underwater operations shows ball-diamond-ball plus two balls on obstruction side and two diamonds on passable side (Rule 27(d)).
USCG OUPV / Master Captain Licence sample questions
Tap any question below to reveal the answer and a plain-English explanation.
Sound Signals (COLREGS) A prolonged blast is defined as a blast of how many seconds?
A. 4 to 6 seconds
B. 2 to 4 seconds ✓
C. 1 to 2 seconds
D. 6 to 8 seconds
Correct — B. A prolonged blast is 4 to 6 seconds (Rule 32(b)).
Right of Way & Rules of the Road In a crossing situation, which vessel is the give-way vessel?
A. The vessel that has the other on its own starboard side
B. The vessel that has the other on its own port side ✓
C. The vessel that is overtaking
D. The smaller vessel
Correct — B. In a crossing situation, the vessel that has the other on her starboard side is the give-way vessel (Rule 15).
Navigation General (Charts, Buoys, Tides) In the IALA-B buoyage system (used in the Americas), a red buoy with the letter 'R' or even number marks:
A. The starboard side of the channel (returning from sea)
B. The port side of the channel (returning from sea) ✓
C. A hazard in the center
D. A safe water mark
Correct — B. In IALA-B, red buoys mark the starboard (right) side of the channel when returning from sea — 'Red Right Returning'.
Deck General (Safety, Distress, Knots) What type of life jacket is approved for use offshore on US commercial vessels?
A. Type I — Offshore Life Jacket (provides 22 lbs buoyancy; will turn unconscious person face-up)
B. Type II — Near-Shore Buoyant Vest ✓
C. Type III — Flotation Aid (not designed to turn unconscious person face-up)
D. Type IV — Throwable device
Correct — B. Type I PFDs are required for offshore commercial use and are designed to turn an unconscious person face up in the water.
Sound Signals (COLREGS) What is the whistle signal for a power-driven vessel underway in or near restricted visibility?
A. Two short blasts every 2 minutes
B. One prolonged blast every 2 minutes
C. One short and one prolonged blast every 2 minutes ✓
D. Two prolonged blasts every 2 minutes
Correct — C. A power-driven vessel making way in restricted visibility sounds one prolonged blast every 2 minutes (Rule 35(a)).
Right of Way & Rules of the Road What is an overtaking vessel?
A. Any vessel with a relative bearing greater than 22.5 degrees ahead of the beam
B. Any vessel coming up on another from a direction more than 22.5 degrees abaft the other vessel's beam
C. Any vessel moving faster than another ✓
D. Any vessel that sounds a passing signal
Correct — C. An overtaking vessel is one approaching from more than 22.5 degrees abaft the beam of the vessel being overtaken (Rule 13).
Navigation General (Charts, Buoys, Tides) What is the color of safe water marks in IALA-B?
A. Red and black horizontal bands
B. Red and white vertical stripes
C. Green with white bands ✓
D. Yellow with black stripes
Correct — C. Safe water marks (mid-channel marks) in IALA-B have red and white vertical stripes.
Deck General (Safety, Distress, Knots) What is a cleat hitch used for?
A. Joining two ropes of different sizes
B. Securing a line to a cleat
C. Creating a fixed loop at the end of a line ✓
D. Stopping a line from running through a block
Correct — C. A cleat hitch secures a line to a cleat, used for mooring lines and similar applications.
About the USCG OUPV / Master Captain Licence test
Prepare for your USCG Captain's License — OUPV (Six-Pack) or Master — with 120 practice questions built from the official exam topics tested by the US Coast Guard.
What's covered
- Navigation Lights (COLREGS): masthead, sidelights, stern, anchor, towing, and special vessels
- Shapes: day signals for vessels at anchor, aground, not under command, RAM, and more
- Sound Signals: whistle signals, restricted visibility, maneuvering and warning
- Rules of the Road: right of way, crossing, head-on, overtaking, narrow channels, restricted visibility
- Navigation General: charts, IALA-B buoyage, compass, tides, dead reckoning, anchoring
- Deck General: PFDs, fire fighting, distress signals, MOB procedures, knots, vessel documentation
How it works
- Study by topic to target your weaknesses
- Timed mock exams mirror the real test format
- Every question has a plain-English explanation
You will be tested on
- Personal survival techniques
- Fire prevention and firefighting
- Elementary first aid at sea
- Personal safety and social responsibility (PSSR)
How TheoryPractice helps you pass
- Real exam-style questions with instant, detailed explanations
- Full timed mock exams that mirror the real test format
- Flashcards & quiz modes from the same question bank
- Progress tracking so you know exactly when you're ready
Topics in this question bank
Personal survival techniques
Fire prevention and firefighting
Elementary first aid at sea
Personal safety and social responsibility (PSSR)
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