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Master of Unlimited Tonnage, Revision & Practice Exams

Master of Unlimited Tonnage. Built from official USCG NMC sample examinations (public domain).
Content last updated 12 June 2026

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The real exam is passed module by module: Rules of the Road requires 90%, most other modules 70%. Chart-plotting modules are taken on paper and not included.

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Frequently asked questions

What score do I need to pass the Master of Unlimited Tonnage exam?

You must pass each module separately. Most modules require 70% to pass.

What modules are on the Master of Unlimited Tonnage exam?

The exam covers 4 modules: Deck General, Deck Safety, Navigation General – Great Lakes and Inland, Great Lakes Topics.

How many practice questions are available for Master of Unlimited Tonnage?

This page includes free sample questions drawn from the official USCG sample examinations, with a full bank of around 227 questions across all modules available with lifetime access.

Are these real USCG exam questions?

Every question comes from the U.S. Coast Guard National Maritime Center's published sample examinations, which are U.S. government works in the public domain. Wheelhouse Prep is not affiliated with or endorsed by the U.S. Coast Guard.

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Sample Master of Unlimited Tonnage practice questions

A selection of free questions from the official USCG sample examinations. Use the interactive modules above for timed, scored drills.

Firefighting equipment requirements for a particular vessel may be found on which document?

  1. Certificate of Registry
  2. Certificate of Inspection ✓
  3. Classification Certificate
  4. Certificate of Seaworthiness

Why: The Certificate of Inspection, issued by the Coast Guard, specifies the vessel's route, manning, and required lifesaving and firefighting equipment. Registry proves nationality; classification certificates address structural and machinery standards.

A vessel proceeding to London, England, from New York makes an unscheduled call at the port of Hamilton, Bermuda. What term is used to denote the voluntary departure from the usual course?

  1. Deviation ✓
  2. Alteration
  3. Liberty
  4. Unscheduled stop

Your vessel is broken down and rolling in heavy seas. How can you reduce the danger of capsizing?

  1. Move all passengers to the stern
  2. Move all passengers to one side of the boat
  3. Rigging a sea anchor ✓
  4. Constantly shifting the rudder

Why: A sea anchor streamed from the bow holds the vessel's head into the seas, keeping her from lying beam-on in the trough where rolling and capsize risk are greatest. Shifting passengers or working the rudder will not control a powerless vessel.

Show all 40 sample questions with answers & explanations

An icebreaker assisting a vessel through an ice field would display a visual signal consisting of the code letter "E" (Echo). What does this signal indicate?

  1. I am altering my course to port
  2. My vessel is stopped and making no way through the water
  3. I am altering my course to starboard ✓
  4. I am operating astern propulsion

U.S. regulations require all tankships of 150 GT and above and all other ships of 400 GT and above, to prepare and maintain which of the following?

  1. A USCG approved shipboard oil pollution emergency plan ✓
  2. A USCG approved oil discharge plan
  3. A USCG approved vapor recovery procedures plan
  4. A USCG approved synthetic plastic discharge plan

Why: U.S. regulations implementing MARPOL (33 CFR 151.26) require a Coast Guard approved Shipboard Oil Pollution Emergency Plan (SOPEP) on oceangoing tankships of 150 GT and above and other ships of 400 GT and above.

Which action has a tendency to happen to a vessel proceeding along the bank of a river or channel with steep banks?

  1. The vessel will increase speed
  2. The vessel will continue in line with the bank
  3. The vessel will sheer away from the bank ✓
  4. The vessel will hug the bank

As the propeller turns, voids are formed on the trailing and leading edges of the propeller blades causing a loss of propulsive efficiency, pitting of the blades, and vibration. Which term defines this effect?

  1. Advance
  2. Edging
  3. Slip
  4. Cavitation ✓

Ship's officers should check every cargo compartment after it is filled with bulk grain to ensure which of the following?

  1. All lighting circuits are energized
  2. All spaces are filled ✓
  3. The correct grade of cargo has been loaded
  4. The heavier grade is in the lower hold

You are loading 465,000 barrels of cargo oil. At 0900 you find that you have loaded 207,000 barrels. At 1030 you find that you have loaded 223,000 barrels. If you continue loading at the same rate, you will finish at approximately __________.

  1. 2100 that night
  2. 0730 the next day
  3. 0910 the next day ✓
  4. 1215 the next day

An annual inspection of a tank vessel shall be made between which of the following months while the Certificate of Inspection is valid?

  1. 8 - 12 months
  2. 8 - 13 months
  3. 9 - 15 months ✓
  4. 12 - 16 months

Which type of weld testing can be used to detect internal flaws?

  1. Chemical reaction
  2. Radiographic ✓
  3. Magnetic particle
  4. Dye penetrant

When evacuating a seaman by helicopter lift, which course should the ship take?

  1. A course that will have the hoist area in the lee of the superstructure.
  2. Downwind so that the apparent wind is close to nil.
  3. A course that will keep a free flow of air, clear of smoke, over the hoist area. ✓
  4. With the wind dead ahead because the helicopter is more maneuverable when going into the wind.

Which is TRUE of the term negative slip on a vessel?

  1. The ship is moving slower than the theoretical propeller speed
  2. The distance a vessel travels when all propulsion has been stopped
  3. The distance a vessel travels in the same direction when rudder has been applied
  4. The ship is moving faster than the theoretical propeller speed ✓

What is the purpose of rigging frapping lines on lifeboat falls?

  1. To give the occupants a safety line when the boat is being lowered from the embarkation level
  2. To reduce the violent swing of the lifeboat at the embarkation level when the tricing pendants are released ✓
  3. To bring the lifeboat close alongside the rail in the embarkation position in order for passengers and crew to board
  4. To secure the lifeboat in the davits when in the stowed position

What is the objective of shoring a damaged bulkhead?

  1. To support and hold the area in the damaged position ✓
  2. To make a watertight seal at the damaged area
  3. To force the warped, bulged, or deformed sections back into place
  4. To withstand subsequent additional damage

What term indicates the immersed body of the vessel aft of the parallel mid-body?

  1. Stern
  2. Run ✓
  3. Counter
  4. Flow

If the current and wind are in opposite directions, what does the sea surface indicate?

  1. The surface indicates a greatly reduced wind speed
  2. The surface indicates a lower wind speed than what really exists
  3. The surface indicates a higher wind speed than what really exists ✓
  4. The surface does not change, each cancels the other

The light characteristic of flashing is used in the Aids to Navigation System on the Western Rivers. Which example is required to utilize this characteristic?

  1. Daymarks with no lateral significance
  2. Preferred channel buoys
  3. Lights marking the right descending bank ✓
  4. Lights marking the left descending bank

The datum from which the predicted heights of tides are reckoned in the tide tables is the same as that used for the charts of the locality. The depression of the datum below mean sea level for Hampton Roads, Virginia is __________.

  1. 4.1 feet
  2. 1.2 feet ✓
  3. between -.7 and +.5 feet
  4. between 1.9 and 3.2 feet

Why is a VLCC (100,000 DWT+) with a 30,000 Shaft Horsepower Steam Turbine slow to respond to engine movements, and has less stopping power than normal ships?

  1. They have a bigger propeller
  2. They have smaller power to weight ratio ✓
  3. They have larger power to weight ratio
  4. They possess smaller propellers

Why: A loaded VLCC has enormous displacement but comparatively modest horsepower, a small power-to-weight ratio, so the engine has little leverage over the ship's huge momentum, making her slow to respond and hard to stop.

Your vessel is being assisted through an ice field in Thunder Bay by the Canadian Coast Guard icebreaker Alexander Henry. The starboard lookout reports that the icebreaker has run up the code flag "N" (November). Which action should you take?

  1. Reduce speed
  2. Reverse your engines
  3. Stop your vessel instantly
  4. Stop your engines ✓

According to the Lifesaving regulations in Subchapter W, fire and abandon ship drills must be held within 24 hours of leaving port if the percentage of the crew that has not participated in drills aboard that particular vessel in the prior month exceeds which percentage?

  1. 5%
  2. 10%
  3. 25% ✓
  4. 40%

Why: Subchapter W requires fire and abandon-ship drills within 24 hours of leaving port whenever more than 25 percent of the crew did not participate in drills aboard that vessel during the previous month.

What is the function of wearing rings found on some centrifugal pumps?

  1. Seal pump shaft against entry of air
  2. Isolate the outlet side from the inlet side ✓
  3. Absorb erosion of high-velocity discharge stream
  4. Dampen the turbulent discharge flow

While proceeding up a channel on course 010° per gyrocompass, you notice a pair of range lights in alignment with the masts of your vessel when viewed forward. A check of the chart shows the range to be 009°T and the variation to be 15°W. If the ship's course is 026°psc, what is the deviation for the present heading?

  1. 2°W ✓
  2. 2°E
  3. 1°W
  4. 1°E

Why: Range true 009 plus variation 15W gives 024 magnetic. On the range dead ahead the compass reads 026 psc. Deviation = magnetic minus compass = 024 - 026 = 2W.

Under the IALA Buoyage Systems, which is TRUE of safe water marks?

  1. They must show a composite group-flashing, Fl(2 + 1), green light
  2. They may show a quick-flashing, Q(9)15s, white light
  3. They may show a white Morse (A) light ✓
  4. They may show a composite group-flashing, Fl(2 + 1), red light

Why: IALA safe water marks show white lights with isophase, occulting, single long-flash, or Morse 'A' rhythm. Composite group flashing (2+1) red or green belongs to preferred-channel marks, and Q(9) is a west cardinal characteristic.

While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships foghorn 5.5 seconds after the signal was sounded. What is the distance to the shore?

  1. 3450 ft (1052 meters)
  2. 3072 ft (936 meters) ✓
  3. 3825 ft (1166 meters)
  4. 2475 ft (754 meters)

Quadrantal error in a gyrocompass has its GREATEST effect on which of the following?

  1. When the vessel is on intercardinal headings ✓
  2. When the vessel is near the equator
  3. When the vessel is on north or south headings
  4. When the vessel is in high latitudes

How can you follow the approach of a dangerous cyclonic storm?

  1. Review the Coast Pilot or Sailing Directions
  2. By a newspaper, a weather map, a weather fax, or a weather forecast ✓
  3. By monitoring the change in the sea temperature
  4. Utilizing the National Weather Service Observing Handbook No.1, Marine Surface Observations

Why: Following a storm's approach requires forecast and synoptic information: weather maps, fax charts, broadcast forecasts, or news reports. Sea temperature and observation handbooks do not show a storm's position and movement.

You are sailing south on the Intracoastal Waterway (ICW) when you sight a green can buoy with a yellow square painted on it. Which of the following is TRUE?

  1. You should leave the buoy to port. ✓
  2. You should pass the buoy close aboard on either side.
  3. The yellow square is retro-reflective material used to assist in sighting the buoy at night.
  4. The buoy marks the end of the ICW in that area.

What is the definition of height of tide?

  1. The vertical distance from the tidal datum to the level of the water at any time ✓
  2. The vertical difference between the heights of low and high water
  3. The vertical difference between a datum plane and the ocean bottom
  4. The vertical distance from the surface of the water to the ocean floor

You are signing on a crew. You can determine the minimum number and qualifications of the crew that you are required to carry by consulting which document?

  1. Articles of Agreement
  2. Fo'c'sle card
  3. Certificate of Inspection ✓
  4. Crew list

What is the function of an air receiver in the compressed air system?

  1. Condenses moisture
  2. Provides overpressure protection
  3. Utilized to store compressed air ✓
  4. Purifies the air

What does blowing tubes accomplish?

  1. Cleans soot deposits from the inside of the stack
  2. Increases boiler efficiency ✓
  3. Eliminates unburned fuel oil residues from the firebox
  4. Flushes away mineral deposits inside the water tubes

In a following sea, a wave has overtaken your vessel and thrown the stern to starboard. To continue along your original course, which action should you take?

  1. Increase speed
  2. Use more left rudder
  3. Use more right rudder ✓
  4. Decrease speed

Why: When a following sea kicks the stern to starboard, the bow swings to port off course. Right rudder checks that swing and brings the bow back. Changing speed alone does not correct the yaw.

On 1 September your 1115 zone time DR position is LAT 25°20.0'N, LONG 28°24.0'W. At that time, you observe the Sun bearing 160.5°psc. The chronometer reads 01h 14m 58s, and the chronometer error is 01m 17s fast. The variation is 13.5°W. What is the deviation of the standard compass?

  1. 2.1°E ✓
  2. 4.1°E
  3. 11.0°W
  4. 11.0°E

When is the effect of wind on exposed areas of the vessel most noticeable?

  1. When turning
  2. When going full ahead
  3. When backing ✓
  4. When going slow ahead

Why: When backing, the vessel moves slowly and the rudder gives little control, so wind on the superstructure dominates, typically the bow falls off downwind.

A channel is stated as having a controlling depth of 38 feet. Which statement is TRUE?

  1. The sides of the channel conform to at least 50% of the controlling depth.
  2. At least 50% of the channel is cleared to the charted depth.
  3. At least 80% of the channel is cleared to the charted depth.
  4. 100% of the channel width is clear to 38 feet. ✓

On Sunday, 8 November, your ship is enroute from Texas City, TX, to Portland, ME. At 0632 ZT, you fix your position at LAT 27°06'N, LONG 90°36'W. When the lower limb of the Sun was two-thirds of a diameter above the visible horizon, the Sun bore 105° per standard magnetic compass. At this time the chronometer read 12h 39m 20s and is 3m 20s slow. If the variation is 3°E, determine the deviation of the standard compass.

  1. 0.8°E ✓
  2. 0.8°W
  3. 3.8°E
  4. 3.8°W

While steaming at 15.0 knots, your vessel consumes 326 barrels of fuel oil per day. In order to reduce consumption to 178 barrels of fuel oil per day, what is the maximum speed the vessel can turn for?

  1. 8.1 knots
  2. 12.2 knots ✓
  3. 11.1 knots
  4. 8.5 knots

You are turning 90 RPM, with a propeller pitch of 24 feet, and an estimated slip of -3%. What is the speed of advance?

  1. 19.2 knots
  2. 20.6 knots
  3. 18.8 knots
  4. 21.9 knots ✓