USCG General Navigation: Master's License

This is an interactive test. Read each question and select the proper answer by clicking on the appropriate answer. If a "Y" appears, your choice is correct. If a "N" appears, more study may be in order.


11: A buoy having red and green horizontal bands would have a light characteristic of __________.


15: What is the length of a nautical mile?


62: Charted depth is the __________.


64: Mean lower low water is the reference plane used for __________.

    N a. all vertical measurements
    N b. heights above water for lights, mountains, etc.
    Y c. soundings on the U.S. east and west coasts
    N d. water depths on the U.S. east coast only

104: What should you apply to a fathometer reading to determine the depth of water?

    N a. Subtract the draft of the vessel.
    Y b. Add the draft of the vessel.
    N c. Subtract the sea water correction .
    N d. Add the sea water correction.

262: Which of the buoy symbols shown indicates a safe water mark? (D032NG )

    N a. A
    N b. B
    N c. C
    Y d. D

278: You are underway on course 050°T and your maximum speed is 11 knots. The eye of a hurricane bears 070°T, 80 miles from your position. The hurricane is moving towards 270°T at 19 knots. If you maneuver at 11 knots to avoid the hurricane, what could be the maximum CPA?

    N a. 84 miles
    N b. 79 miles
    N c. 74 miles
    Y d. 66 miles

338: The illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "N" represents __________. (D042NG )

    N a. hail
    N b. freezing rain
    Y c. rain
    N d. snow

391: When outbound from a U.S. port, a buoy displaying a flashing red light indicates __________.

    N a. a junction with the preferred channel to the left
    N b. a sharp turn in the channel to the right
    Y c. the port side of the channel
    N d. a wreck to be left on the vessel's starboard side

493: The picture shown represents the geographic location of a vessel and the radar presentation at the same time. Which statement is TRUE? (D011NG )

    N a. Ship No. 1 is not detected due to the shadow effect of the headland.
    N b. The small island is not detected due to the effect of beam width.
    Y c. A tangent bearing of the headland to the south-southeast should be corrected by adding one-half of the beam width.
    N d. Ship No. 2 is not detected due to the reflective mass of the background mountain overpowering the ship's reflective signals.

517: On 5 March 1983, at 0630 EST (ZD +5), what will be the predicted height of tide at Ocracoke, Ocracoke Inlet, NC?

    Y a. 0.1 foot
    N b. 1.2 feet
    N c. 1.9 feet
    N d. 2.3 feet

585: What great circle is always needed to form the astronomical triangle?

    N a. Celestial Equator
    N b. Prime Meridian
    Y c. Celestial Meridian
    N d. Prime Vertical Circle

692: Which publication should you check for complete information on Puget Sound weather conditions?

    N a. Sailing Directions
    N b. Light List
    Y c. Coast Pilot
    N d. Chart of the area

801: You are entering an African port and see ahead of you a red can-shaped buoy. What action should you take?

    Y a. Alter course to leave the buoy to port
    N b. Alter course to leave the buoy to starboard
    N c. Pass the buoy close aboard on either side
    N d. Pass the buoy well clear on either side

891: Under the IALA-A Buoyage System, a buoy indicating the preferred channel is to port would have __________.

    N a. an even number
    N b. an odd number
    N c. a pillar shape
    Y d. horizontal bands

891: Under the IALA-A Buoyage System, a buoy indicating the preferred channel is to port would have __________.

    N a. an even number
    N b. an odd number
    N c. a pillar shape
    Y d. horizontal bands

892: When a buoy is in position only during a certain period of the year, where may the dates when the buoy is in position be found?

    Y a. Light List
    N b. Notice to Mariners
    N c. On the chart
    N d. Coast Pilot

985: A time diagram is a diagram on the plane of the __________.

    N a. celestial meridian
    Y b. celestial equator
    N c. celestial horizon
    N d. principal vertical circle

1022: What is the approximate geographic range of Fenwick Island Light, Delaware, if your height of eye is 37 feet (11.6 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 24.8 nm
    Y b. 17.8 nm
    N c. 15.9 nm
    N d. 10.3 nm

1086: When crossing a front isobars tend to __________.

    Y a. change from smooth curves within the air mass to sharp bends at the front
    N b. change from sharp bends within the air mass to smooth curves at the front
    N c. pass smoothly across the front with no change
    N d. become closer together at the front and pass through in straight lines

1126: When a warm air mass is adjacent to a cold air mass, the separation line between the two is called a(n) __________.

    Y a. front
    N b. isobar
    N c. isotherm
    N d. equipotential line

1137: When the declination of the Moon is 0°12.5'S, you can expect some tidal currents in Gulf Coast ports to __________.

    Y a. become weak and variable
    N b. exceed the predicted velocities
    N c. become reversing currents
    N d. have either a double ebb or a double flood

1175: Solid green arrows on the main body of a pilot chart indicate __________.

    N a. prevailing wind directions
    Y b. prevailing ocean current directions
    N c. probable surface current flow
    N d. shortest great circle routes

1186: As a cold front passes an observer, pressure __________.

    N a. drops and winds become variable
    Y b. rises and winds become gusty
    N c. drops and winds become gusty
    N d. rises and winds become variable

1243: Magnetic heading differs from compass heading by __________.

    N a. compass error
    N b. true heading
    N c. variation
    Y d. deviation

1246: What weather change accompanies the passage of a cold front in the Northern Hemisphere?

    N a. Wind shift from northeast clockwise to southwest
    N b. Steady dropping of barometric pressure
    N c. Steady precipitation, gradually increasing in intensity
    Y d. A line of cumulonimbus clouds

1254: Lighted white and orange buoys must show which color light?

    N a. Orange
    Y b. White
    N c. Red
    N d. Alternating yellow and white

1284: The Sailing Directions (Enroute) contain information on all of the following EXCEPT __________.

    Y a. ocean currents
    N b. outer dangers to navigation
    N c. tidal currents
    N d. major port anchorages

1336: On the approach of a warm front, barometric pressure usually __________.

    Y a. falls
    N b. is steady
    N c. is uncertain
    N d. rises

1516: Which correction(s) must be applied to an aneroid barometer?

    Y a. Instrument error and height error
    N b. Instrument error only
    N c. Height error only
    N d. Instrument error and latitude correction

1542: To find a magnetic course from a true course you must apply __________.

    N a. magnetic anomalies (local disturbances)
    N b. deviation
    Y c. variation
    N d. deviation and variation

1556: The vertical distance from the tidal datum to the level of the water is the __________.

    N a. range of tide
    N b. charted depth
    Y c. height of tide
    N d. actual water depth

1687: Which statement is TRUE when comparing cold and warm fronts?

    Y a. Cold fronts are more violent and of shorter duration.
    N b. Cold fronts are milder and last longer.
    N c. They are very similar with the exception of wind direction.
    N d. Warm fronts are more violent and of longer duration.

1709: The Beaufort scale is used to estimate the __________.

    N a. wind direction
    N b. percentage of cloud cover
    Y c. wind speed
    N d. barometric pressure

1738: In the Northern Hemisphere, the right half of the storm is known as the dangerous semicircle because __________.

    N a. The wind speed is greater here since the wind is traveling in the same general direction as the storm's track
    N b. the direction of the wind and seas might carry a vessel into the path of the storm
    N c. the seas are higher because of greater wind speed
    Y d. All of the above

1762: In high latitudes, celestial observations can be made over a horizon covered with pack ice by bringing the sun tangent to the ice and __________.

    N a. adding 30° of arc to the sight
    Y b. using a dip correction based on the height of eye above the ice
    N c. doubling the semidiameter correction
    N d. using a dip correction from table 22 in Bowditch Vol. II

1842: What is the major problem with taking high altitude observations?

    N a. Possible errors due to unusual refraction may exist.
    N b. The tables are not as accurate due to inherent errors in the spherical triangle at high altitudes.
    N c. Rapidly changing altitudes make it difficult to get an accurate altitude.
    Y d. It is difficult to establish the point where the sextant is vertical to the horizon.

1866: What term is used to describe a tank barge constructed with the structural framing inside the cargo tank and the side shell plating containing the cargo?

    Y a. Single hull
    N b. Shell plated
    N c. Hopper type
    N d. Independent tank

1964: The great circle on the celestial sphere that passes through the zenith and the north and south poles is the __________.

    N a. hour circle
    N b. prime vertical
    Y c. principal vertical
    N d. ecliptic

2008: What term is used to describe a tank barge constructed with the structural framing outside the cargo tank and the cargo tank plating separated from the shell plating?

    N a. Shell plated
    Y b. Double hull
    N c. Hopper type
    N d. Independent tank

2021: While on watch, you notice that the air temperature is dropping and is approaching the dew point. Which type of weather should be forecasted?

    N a. Hail
    N b. Heavy rain
    N c. Sleet
    Y d. Fog

2114: Vessels regularly navigating rivers above Cairo, Illinois, shall at all times have on board a copy of __________.

    N a. Sailing Directions
    N b. Nautical Almanac for the year
    N c. U.S. Coast Pilot
    Y d. U.S. Army Corps of Engineers Regulations (Blue Book)

2144: Yesterday your chronometer read 02h 59m 58s at the 1500 GMT time tick. Today the chronometer reads 03h 00m 02s at the 1500 GMT time tick. What is the chronometer error?

    Y a. 02s fast
    N b. 03h 00m 02s fast
    N c. +3s
    N d. -3s

2202: You have completed the magnetic compass adjustments on magnetic east and magnetic south. The vessel is now steady on magnetic west but the compass reads 276°. What action should be taken?

    N a. Adjust the compass with the athwartships magnets until the compass reads 264°.
    Y b. Adjust the compass with the fore-and-aft magnets until the compass reads 273°.
    N c. Adjust the compass with the quadrantal spheres until the compass reads 270°.
    N d. Adjust the compass with the athwartships magnets until the compass reads 273°.

2229: A vessel is heading magnetic north and its magnetic compass indicates a heading of 003°. What action should be taken to remove this error during compass adjustment?

    Y a. If the red ends are to port the athwartships magnets should be raised.
    N b. If the blue ends are to port the athwartships magnets should be raised.
    N c. If the red ends are forward the fore-and-aft magnets should be lowered.
    N d. If the blue ends are forward the fore-and-aft magnets should be raised.

2239: A flashing green light displayed at a single lock means that the lock is __________.

    Y a. ready for entrance
    N b. ready for entrance, but gates cannot be closed completely
    N c. being made ready for entrance
    N d. not ready for entrance

2322: You have completed the magnetic compass adjustments on magnetic east and magnetic south. The vessel is now steady on magnetic north but the compass reads 356°. Which action should be taken?

    N a. Use the fore-and-aft magnets and adjust the compass until it reads 358°.
    Y b. Use the athwartships magnets and adjust the compass until it reads 358°.
    N c. Use the fore-and-aft magnets and adjust the compass until it reads 000°.
    N d. Use the quadrantal spheres and adjust the compass until it reads 000°.

2484: What is the equivalent of 1°53' in time units?

    N a. 3 min. 16 sec.
    N b. 5 min. 28 sec.
    N c. 6 min. 43 sec.
    Y d. 7 min. 32 sec.

2509: All persons or vessels within the lock area, including the lock approach channels, come under the authority of the __________.

    N a. dockmaster
    N b. dock captain
    Y c. lockmaster
    N d. lock foreman

2578: You must draw a plotting sheet covering latitudes 49°N to 53°N and longitudes 179°E to 178°W. If the distance between latitude 49°N to 53°N is 16 inches, what is the distance between the meridians of 1° of longitude?

    N a. 2.12 inches
    N b. 2.33 inches
    Y c. 2.56 inches
    N d. 2.81 inches

2650: In the celestial equator system of coordinates what is equivalent to the colatitude of the Earth system of coordinates?

    N a. Coaltitude
    N b. Zenith distance
    Y c. Polar distance
    N d. Declination

2887: The letter B in illustration D006NG represents the __________.

    N a. visible horizon
    N b. sensible horizon
    Y c. geoidal horizon
    N d. celestial horizon

2891: Twenty-three meters equals __________.

    N a. 17.50 feet
    Y b. 75.46 feet
    N c. 96.00 feet
    N d. 104.99 feet

2895: A white buoy with an orange rectangle on it is a(n) __________.

    N a. junction buoy
    N b. safe water buoy
    Y c. informational buoy
    N d. All of the above

2923: You should plot your dead reckoning position __________.

    N a. from every estimated position
    Y b. from every fix or running fix
    N c. every three minutes in pilotage waters
    N d. only in pilotage waters

3038: In low latitudes, the low(s) of the diurnal variation of pressure occur(s) at __________.

    N a. noon
    N b. noon and midnight
    N c. 1000 and 2200
    Y d. 0400 and 1600

3063: Which of the following must the electronic chart of an ECDIS display, as required by IMO/IHO?

    N a. Hydrography
    N b. Ferry routes
    N c. Regulatory boundaries
    Y d. All of the above

3075: Chart information details to be used in ECDIS should be the latest edition of information originated by a government-authorized hydrographic office and conform to the standards of (the) __________.

    N a. International Maritime Organization
    Y b. International Hydrographic Organization
    N c. NASA
    N d. US Coast Guard

3117: With respect to automatic identification systems (AIS), which information is required to be broadcast every 1 to 10 seconds?

    Y a. Time stamp
    N b. IMO number
    N c. Type of vessel
    N d. Vessel's maximum displacement

3125: Which of the following statements is TRUE regarding automatic identification systems (AIS)?

    N a. AIS is designed to replace ARPA, maneuvering boards, and visual bearings as a means to ascertain the risk of collision.
    Y b. AIS provides near real-time information regarding another vessel's speed over ground and heading regardless of visibility.
    N c. AIS will not provide information on another vessel if that vessel is indistinguishable in radar sea clutter.
    N d. AIS can be relied upon as the sole means to determine course changes due to other AIS equipped traffic.