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.


17: "Stand" of the tide is that time when __________.


17: "Stand" of the tide is that time when __________.


23: If Loran-C signals become unsynchronized, the receiver operator is warned because __________.


30: When taking an amplitude, the Sun's center should be observed on the visible horizon when __________.

    Y a. in high latitudes
    N b. the Sun is near or at a solstice
    N c. the declination is of a different name from the latitude
    N d. the Sun's declination is at or near 0°

107: The average height of the surface of the sea for all stages of the tide over a 19 year period is called __________.

    N a. mean high water
    N b. mean low water
    N c. half-tide level
    Y d. mean sea level

250: Weather systems in the middle latitudes generally travel from __________.

    Y a. west to east
    N b. east to west
    N c. north to south
    N d. None of the above

312: The depth of water on a chart is indicated as 23 meters. This is equal to __________.

    N a. 11.5 fathoms
    Y b. 12.6 fathoms
    N c. 69.0 feet
    N d. 78.6 feet

345: A navigator fixing a vessel's position by radar __________.

    N a. should never use radar bearings
    N b. should only use radar bearings when the range exceeds the distance to the horizon
    Y c. can use radar information from one object to fix the position
    N d. must use information from targets forward of the beam

349: The direction of the southeast trade winds is a result of the __________.

    N a. equatorial current
    N b. humidity
    Y c. rotation of the earth
    N d. change of seasons

381: A nun buoy will __________.

    N a. be green in color
    Y b. have an even number
    N c. be left to port when entering from seaward
    N d. be cylindrical in shape

411: When entering from seaward, a buoy displaying a single-flashing red light would indicate __________.

    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 starboard side of the channel
    N d. a wreck to be left on the vessel's port side

445: The values of the Greenwich hour angle and declination, tabulated in all almanacs, are for the __________.

    N a. upper limb of a celestial body
    N b. lower limb of a celestial body
    Y c. centers of the various celestial bodies
    N d. lower limb of the Sun and Moon; center of the stars and planets

462: For what purpose would using a Lambert conformal chart be more convenient than using a Mercator?

    Y a. Plotting radio bearings over a long distance
    N b. Determining latitude and longitude of a fix
    N c. Measuring rhumb line distances
    N d. Measuring rhumb line directions

560: On 14 April 1981, a back sight is observed of the lower limb of the Sun. The height of eye is 45 feet. The index error is 2.5' on the arc. The sextant altitude (hs) is 117°14.6'. What is the observed altitude (Ho)?

    N a. 63°01.9'
    N b. 63°03.4'
    N c. 63°07.4'
    Y d. 63°09.9'

561: Buoys which mark dredging areas are painted __________.

    N a. black
    Y b. yellow
    N c. green
    N d. red

564: A hygrometer is a device used for determining __________.

    N a. the absolute temperature
    N b. atmospheric pressure
    N c. wind velocity
    Y d. relative humidity

633: You have another ship overtaking you close aboard to starboard. You have 3 radar targets bearing 090° relative at ranges of .5 mile, 1 mile, and 1.5 miles. In this case, the unwanted echoes are called __________.

    Y a. multiple echoes
    N b. spoking
    N c. indirect echoes
    N d. side-lobe echoes

735: The period of the Earth's revolution from perihelion to perihelion is the __________.

    N a. astronomical year
    Y b. anomalistic year
    N c. solar year
    N d. sidereal year

740: A very light breeze that causes ripples on a small area of still water is a __________.

    Y a. cat's paw
    N b. hog's breath
    N c. williwaw
    N d. chinook

741: What is the light phase characteristic of a lighted isolated-danger mark?

    N a. Interrupted quick flashing
    N b. Very quick flashing
    N c. Long flashing
    Y d. Group flashing

824: An "atoll cloud" forming over an island due to heating of the land during the daytime would be which type?

    N a. Cirrus
    Y b. Cumulus
    N c. Stratus
    N d. Nimbus

849: The Light List shows that a navigational light has a nominal range of 12 miles and a height above water of 25 feet (7.6 meters). Your height of eye is 30 feet (9.1 meters) and the visibility is 0.5 mile. At what approximate range will you first sight the light?

    N a. 0.5 mile
    Y b. 1.4 miles
    N c. 5.2 miles
    N d. 12.0 miles

1023: Which compensates for induced magnetism in the horizontal soft iron of a vessel?

    Y a. Iron spheres mounted on the binnacle
    N b. A single vertical magnet under the compass
    N c. The Flinders bar
    N d. Magnets in trays inside the binnacle

1147: To make sure of getting the full advantage of a favorable current, you should reach an entrance or strait at which time in relation to the predicted time of the favorable current?

    N a. One hour after
    N b. At the predicted time
    Y c. 30 minutes before
    N d. 30 minutes before flood, one hour after an ebb

1265: When reporting wind direction, you should give the direction in __________.

    Y a. true degrees
    N b. magnetic compass degrees
    N c. relative degrees
    N d. isobaric degrees

1269: The Light List indicates that a light has a nominal range of 14 miles and is 42 feet (12.7 m) high. If the visibility is 16 miles and your height of eye is 20 feet (6.1 m), at which approximate distance will you sight the light?

    N a. 20.1 miles
    N b. 16.0 miles
    Y c. 12.8 miles
    N d. 7.6 miles

1290: In addition to the National Weather Service, what agency provides plain-language radio weather advisories for the coastal waters of the United States?

    N a. National Geospatial-Intelligence Agency
    N b. U.S. Hydrological Survey
    Y c. U.S. Coast Guard
    N d. American Meteorological Service

1325: You change course entering port and steady up on a range with the lights in line. After a few minutes you observe the range lights as shown. You should alter your heading to the __________. (D047NG )

    N a. left, and when the range lights are in line again, resume your original heading
    N b. right, and when the range lights are in line again, steer to keep them dead ahead
    Y c. left, and when the range lights are in line again, steer to keep them in line fine on the starboard bow
    N d. right, and when the range lights are in line again, steer to keep them in line fine on the port bow

1376: What is typical of warm front weather conditions?

    N a. An increase in pressure
    N b. A wind shift from southwest to northwest
    N c. Scattered cumulus clouds
    Y d. Steady precipitation

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

1548: The Illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "K" represents a __________. (D042NG )

    Y a. hurricane
    N b. thunderstorm
    N c. convergence zone
    N d. convergence line

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

1634: A lighted buoy to be left to starboard, when entering a U.S. port from seaward, shall have a __________.

    Y a. red light
    N b. white light
    N c. green light
    N d. light characteristic of Morse (A)

1665: Air circulation is caused or affected by __________.

    N a. the rotation of the earth on its axis
    N b. convection currents caused by differences in radiant heating between equatorial and polar regions
    N c. mountain ranges
    Y d. All of the above

1770: A Doppler speed log indicates speed over ground __________.

    N a. at all times
    Y b. in the bottom return mode
    N c. in the volume reverberation mode
    N d. only when there is no current

1852: When plotting a circle of equal altitude for a high altitude sight, the radius of the circle is determined by the formula __________.

    Y a. 90° - Ho
    N b. 180° - GHA
    N c. GHA - LHA
    N d. z - d

1859: While proceeding downriver (descending) you sight a red diamond-shaped panel with small, red reflector squares in each corner on the left bank. Under the U.S. Aids to Navigation System on the Western Rivers this is a __________.

    N a. special purpose signal
    N b. passing daymark
    Y c. crossing daymark
    N d. cable crossing

1909: In the horizon system of coordinates what is equivalent to the equator on the Earth?

    N a. Prime vertical circle
    N b. Principal vertical circle
    N c. Parallels of altitude
    Y d. Horizon

1916: The prime vertical is the reference point from which the angle of which type of observation is measured?

    N a. Sextant angle
    N b. Azimuth
    Y c. Amplitude
    N d. Local apparent noon

1960: Astronomical refraction causes a celestial body to appear __________.

    N a. to the left of its position in the Northern Hemisphere and to the right in the Southern Hemisphere
    N b. to the right of its position in the Northern Hemisphere and to the left in the Southern Hemisphere
    Y c. higher than its actual position
    N d. lower than its actual position

2028: Which stock number indicates an NGA (NIMA) chart designed for navigation and anchorage in a small waterway?

    N a. WOAZC17
    N b. LCORR5876
    Y c. 15XHA15883
    N d. PILOT55

2110: You are underway in a vessel with a draft of 6.0 feet. You are in an area where the charted depth of the water is 4 fathoms. You would expect the depth of water beneath your keel to be approximately __________.

    N a. 12 feet
    Y b. 18 feet
    N c. 24 feet
    N d. 30 feet

2115: Vessels regularly navigating rivers above Cairo, Illinois, shall at all times have on board a copy of __________.

    Y a. U.S. Army Corps of Engineers Regulations (Blue Book)
    N b. Light List Vol. V
    N c. U.S. Coast Pilot
    N d. None of the above

2189: 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?

    N a. If the blue ends are to port and the athwartships tray is at the bottom, you should add some more magnets.
    N b. If the blue ends are to port and the athwartships tray is at the top, you should add some more magnets.
    N c. If the red ends are to port, you should lower the athwartships tray.
    Y d. If the red ends are to port and the tray is at the bottom, you should raise the tray.

2336: The period of revolution of the Moon is __________.

    N a. 24 hours
    Y b. about 27.3 days
    N c. 365 days
    N d. about 19 years

2342: What happens because of augmentation?

    Y a. The Moon appears larger as the elevation increases.
    N b. The Sun appears larger when viewed against the darker background of the horizon.
    N c. The horizon appears elevated when observing a bright Sun or Moon at low altitudes.
    N d. The Moon appears larger at the full Moon.

2434: A vessel is heading magnetic east and its magnetic compass indicates a heading of 093°. What action should be taken to remove this error during compass adjustment?

    N a. If the red ends of the magnets are aft you should lower the fore-and-aft tray.
    Y b. If the red ends of the magnets are forward, and the fore-and-aft tray is at the bottom, you should remove some magnets.
    N c. If the red ends of the magnets are to port you should raise the athwartships tray.
    N d. If the red ends of the magnets are to port, and the athwartships tray is at the top, you should reverse the magnets.

2456: An orange and white buoy marking an area where operating restrictions are in effect will be marked with which symbol?

    N a. Open-faced diamond
    N b. Diamond with a cross
    Y c. Circle
    N d. Rectangle

2538: The light characteristic of composite group flashing (2 + 1) is used in the Aids to Navigation System on the Western Rivers for lights on __________.

    N a. the right descending bank
    N b. the left descending bank
    Y c. preferred-channel buoys
    N d. daymarks with no lateral significance

2572: The dividing meridian between zone descriptions -4 and -5 is __________.

    N a. 60°00'E
    Y b. 67°30'E
    N c. 75°00'E
    N d. 60°00'W

2583: You are in the Northern Hemisphere and a tropical wave is located 200 miles due west of your position. Where will the wave be located 24 hours later?

    N a. In the same place
    N b. Closer and to the west
    N c. Closer and to the east
    Y d. Farther away to the west

2706: The following types of vessels are awaiting lockage on the upper Mississippi. Which type of vessel is normally passed through the lock first?

    N a. Pleasure craft
    N b. Commercial towboats
    Y c. Commercial passenger vessels
    N d. Commercial fishing vessels

2768: Which type of daymark is used to mark the starboard side of the channel when entering from sea?

    N a. Red and white octagon
    N b. Black and white diamond
    Y c. Red triangle
    N d. Green square

2870: Steam fog is most likely to occur on the Mississippi and Ohio Rivers in __________.

    N a. spring, around late evening
    N b. spring, around early evening
    Y c. fall, around early morning
    N d. fall, around midday

2900: Who should be consulted for changing conditions of controlling depths in major channels?

    N a. U.S. Coast Guard
    N b. National Geospatial-Intelligence Agency
    N c. National Ocean Service
    Y d. U.S. Army Corps of Engineers

2940: On the Corps of Engineer's Navigation Maps, the channel is __________.

    N a. midway between the banks
    N b. indicated by depths (in feet)
    Y c. indicated by a broken line
    N d. not indicated

2954: You are inbound in a channel marked by a range. The range line is 309°T. You are steering 306°T. The range appears as shown and is closing. Which action should you take? (D047NG )

    N a. Continue on the present heading until the range is in line then alter course to the left.
    N b. Immediately alter course to the right to bring the range in line.
    Y c. Continue on course until the range is closed, then alter course to the right.
    N d. Immediately alter course to 309°T.

2979: You take a bearing of 356° of a lighthouse. What bearing of another object would give the best fix?

    N a. 013°
    Y b. 082°
    N c. 176°
    N d. 201°

2989: On 13 November 1981 you observe a back sight of the lower limb of the Moon. The sextant altitude (hs) is 110°31.2'. The height of eye is 46 feet and the index error is 2.0' off the arc. The horizontal parallax is 61.3'. What is the observed altitude (Ho)?

    N a. 70°41.4
    N b. 70°15.4'
    Y c. 70°11.4'
    N d. 70°02.2

3061: In a river subject to tidal currents, the best time to dock a ship without the assistance of tugs is __________.

    N a. at flood tide
    N b. at high water
    N c. when there is a following current
    Y d. at slack water