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.


31: When approaching a preferred-channel buoy, the best channel is NOT indicated by the __________.


35: You are on a vessel at 0400 ZT on 3 July, and the ZD for your position is -8. What is the GMT?


51: In the U.S. Aids to Navigation System, red and green horizontally-banded buoys mark __________.


114: All echo-sounders can measure the __________.

    N a. actual depth of water
    Y b. actual depth of water below keel
    N c. average depth from waterline to hard bottom
    N d. average depth of water to soft bottom

208: The moon is full and at perigee on 20 January 1983. What is the maximum current you could expect at 2350 (ZD +5) at Nantucket Shoals?

    N a. 0.5 knot
    N b. 0.7 knot
    N c. 0.8 knot
    Y d. 1.0 knot

209: The West Wind Drift is located __________.

    Y a. near 60°S
    N b. on each side of the Equatorial Current
    N c. in the North Atlantic between Greenland and Europe
    N d. in the South Pacific near 5°S

209: The West Wind Drift is located __________.

    Y a. near 60°S
    N b. on each side of the Equatorial Current
    N c. in the North Atlantic between Greenland and Europe
    N d. in the South Pacific near 5°S

236: The winds with the greatest effect on the set, drift, and depth of the equatorial currents are the __________.

    N a. doldrums
    N b. horse latitudes
    Y c. trade winds
    N d. prevailing westerlies

248: What is the index error of sextant A in illustration D050NG? (D050NG )

    N a. 0° 10' off the arc
    N b. 0° 10' on the arc
    N c. 3° 00' off the arc
    Y d. 4° 20' off the arc

267: You are inbound in a channel marked by a range. The range line is 309°T. You are steering 306°T and have the range in sight as shown. The range continues to open. What action should you take? (D047NG )

    N a. Alter course to the right to 309°T or more to bring the range in line.
    Y b. Alter course to the left until the range closes, then steer to the left of 306°T.
    N c. Alter course to the left to close the range, then alter course to 309°T.
    N d. Maintain course as it is normal for the range to open as you get close.

287: 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 __________.

    N a. between -.7 and +.5 feet
    N b. between 1.9 and 3.2 feet
    N c. 4.1 feet
    Y d. 1.2 feet

545: The arc of a great circle which passes through the body and celestial poles is part of the __________. (D007NG )

    Y a. hour circle
    N b. diurnal circle
    N c. observer's meridian
    N d. altitude circle

551: Spoil grounds, anchorage areas, cable areas, and military exercise areas are all marked by yellow buoys. Which special mark on the buoy will indicate the specific area you are in?

    N a. A topmark triangular in shape
    N b. A topmark spherical in shape
    Y c. Lettering on the buoy
    N d. A topmark consisting of two cones with the points up

635: A low HDOP (Horizontal Dilution of Precision) number such as 2 indicates a __________.

    N a. poor fix
    Y b. good fix
    N c. poor signal quality
    N d. good signal quality

771: Under the IALA Buoyage Systems, a spherical buoy will mark the __________.

    Y a. safe water
    N b. port side of the channel
    N c. a hazard to navigation
    N d. the position of an underwater cable

771: Under the IALA Buoyage Systems, a spherical buoy will mark the __________.

    Y a. safe water
    N b. port side of the channel
    N c. a hazard to navigation
    N d. the position of an underwater cable

896: The wind direction around a low pressure area in the Northern Hemisphere is __________.

    N a. clockwise and inward
    N b. clockwise and outward
    Y c. counterclockwise and inward
    N d. counterclockwise and outward

899: A latitude line will be obtained by observing a body __________.

    N a. on the prime vertical
    N b. on the celestial horizon
    Y c. at lower transit
    N d. on the Greenwich meridian

918: At 1200 ZT, on 31 August, your position is LAT 43°14'S, LONG 175°44'E. You are preparing a weather report form, WS Form B-80. How should you encode the first three groups after the call sign if you estimate the wind? (D041NG )

    N a. 01003, 94314, 51757
    Y b. 31003, 99432, 31757
    N c. 31123, 99432, 31754
    N d. 31243, 94314, 31757

950: Where is the dangerous semicircle located on a hurricane in the Southern Hemisphere?

    Y a. To the left of the storm's track
    N b. To the right of the storm's track
    N c. In the high pressure area
    N d. On the south side

979: Which kind of conditions would you observe as the eye of a storm passes over your vessel's position?

    Y a. Huge waves approaching from all directions, clearing skies, light winds, and an extremely low barometer
    N b. Flat calm seas, heavy rain, light winds, and an extremely low barometer
    N c. Flat calm seas, heavy rain, light winds, and high pressure
    N d. Huge waves approaching from all directions, clearing skies, light winds, and high pressure

1020: The Light List shows that a navigational light has a nominal range of 6 miles and a height above water of 18 feet (5.5 meters). Your height of eye is 40 feet (12.2 meters) and the visibility is 27.0 miles. At which approximate range will you first sight the light?

    N a. 5.6 miles
    N b. 6.4 miles
    Y c. 9.8 miles
    N d. 12.1 miles

1036: A frontal thunderstorm is caused by __________.

    N a. pronounced local heating
    N b. wind being pushed up a mountain
    Y c. a warm air mass rising over a cold air mass
    N d. an increased lapse rate caused by advection of warm surface air

1046: The probability of a sudden wind may be foretold by __________.

    N a. a partly cloudy sky
    N b. an overcast sky
    Y c. a fast approaching line of dark clouds
    N d. the formation of cumulus clouds in the sky

1144: Freezing salt water spray should be anticipated when the air temperature drops below what temperature?

    N a. 32°F (0.0°C)
    Y b. 28°F (-2.2°C)
    N c. 0°F (-17.8°C)
    N d. -40°F (-28.9°C)

1154: The speed at which an ocean wave system advances is called __________.

    N a. wave length
    N b. ripple length
    Y c. group velocity
    N d. wave velocity

1207: What will be the velocity of the tidal current at New London Harbor Entrance, CT, at 1615 EST (ZD +5) on 26 December 1983?

    Y a. 0.2 knot
    N b. 0.4 knot
    N c. 0.7 knot
    N d. 0.9 knot

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

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

1444: Stratocumulus clouds are indicated by which number? (D039NG )

    N a. 1
    N b. 4
    Y c. 6
    N d. 7

1466: Advection fog is most commonly caused by __________.

    N a. air being warmed above the dew point
    N b. saturation of cold air by rain
    N c. a rapid cooling of the air near the surface of the Earth at night
    Y d. warm moist air being blown over a colder surface

1467: Determine the time after 0730 EST (ZD +5) when the velocity of the current will be 2.1 knots on 26 March 1983, at Fort Pulaski, GA.

    N a. 0802
    N b. 0812
    N c. 0821
    Y d. 0840

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

1517: When determining compass error by an azimuth of Polaris, you enter the Nautical Almanac with the __________.

    N a. GHA Aries
    Y b. LHA Aries
    N c. LHA Polaris
    N d. GHA Polaris

1593: Apparent altitude is sextant altitude corrected for __________.

    N a. parallax and personal error
    Y b. inaccuracies in the reading and reference level
    N c. visibility and magnitude
    N d. All of the above are correct

1614: Hot air can hold __________.

    N a. less moisture than cold air
    Y b. more moisture than cold air
    N c. the same amount of moisture as cold air
    N d. moisture independent of air temperature

1644: Which scale is used to estimate wind speed by observing sea conditions __________.

    N a. Metric scale
    N b. Wind scale
    N c. Coriolis scale
    Y d. Beaufort scale

1647: Cumulonimbus clouds are formed by __________.

    Y a. vertical air movements
    N b. heavy rainstorms
    N c. horizontal air movements
    N d. any movement of moist air

1695: Compared to a low pressure system, generally the air in a high is __________.

    N a. warmer, less dense, and less stable
    Y b. cool, more dense, and drier
    N c. muggy and cloudy
    N d. extremely moist with high relative humidity

1697: In the Northern Hemisphere, if the center of a high pressure area is due west of you, what wind direction would you expect?

    N a. South to west
    N b. South to east
    Y c. North to west
    N d. North to east

1782: You are on course 027°T and take a relative bearing to a lighthouse of 220°. What is the true bearing to the lighthouse?

    N a. 113°
    N b. 193°
    Y c. 247°
    N d. 279°

1836: At evening stars, the first stars that should be observed are those with an azimuth in what quadrant?

    N a. Southern
    N b. Western
    N c. Northern
    Y d. Eastern

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

1941: IN REGION A of the IALA Buoyage System, when entering from seaward, the starboard side of a channel would be marked by a __________.

    N a. red can buoy
    N b. red conical buoy
    N c. green can buoy
    Y d. green conical buoy

1961: What kind of pressure systems travel in tropical waves?

    N a. Subsurface pressure
    N b. Terrastatic pressure
    N c. High pressure
    Y d. Low pressure

1979: The principal vertical circle is that great circle on the celestial sphere that passes through the __________.

    N a. zenith and the celestial body
    Y b. zenith and the north and south poles
    N c. poles and Greenwich
    N d. zenith and is parallel to the horizon

2068: The illustration represents a movable dam. If there is high water and the wickets are down so that there is an unobstructed navigable pass through the dam, what light(s) will be shown at D if the lock walls and piers are not awash? (D037NG )

    Y a. One red light
    N b. Two red lights
    N c. Three red lights
    N d. One amber light

2086: You are downbound on the Ohio River locking through Greenup. The chamber has been emptied and the lower gates are open. You hear one short blast of the whistle from the lock. You should __________.

    Y a. leave the lock
    N b. hold up until another tow enters the adjacent lock
    N c. tie off to the guide wall until the river is clear of traffic
    N d. hold in the lock chamber due to a malfunction with the gate

2152: Permanent magnetism is found in __________.

    Y a. hard iron
    N b. soft iron
    N c. vertical iron only
    N d. horizontal iron only

2286: Which light signal indicates that you have permission to enter a lock on the Ohio River?

    N a. Steady red
    N b. Flashing amber
    N c. Steady green
    Y d. Flashing green

2439: Which statement about the time diagram in illustration D008NG is TRUE? (D008NG )

    Y a. You are in east longitude.
    N b. The Sun is setting for you.
    N c. Your date is different from the Greenwich date.
    N d. The GHA is approximately 160°.

2490: A vertex of the navigational triangle is NOT located at the __________.

    N a. elevated pole
    N b. celestial body
    N c. zenith
    Y d. coaltitude

2532: You must construct a Mercator plotting sheet on a piece of paper measuring 28" by 32". The area includes latitude 32°S to 39°S and longitude 005°E to 003°W. Allow a one-half inch neat line on all sides. What is the maximum distance between each degree of longitude that will permit the area of the plotting sheet to be drawn within the stated limitations?

    Y a. 3.38 inches
    N b. 3.62 inches
    N c. 3.79 inches
    N d. 3.95 inches

2792: You take a bearing of 142° and 259° of two objects. Which bearing of a third object will give the best fix?

    N a. 081°
    N b. 238°
    Y c. 201°
    N d. 234°

2836: The correction tables in the front of the Nautical Almanac for use with sun sights do NOT include the effects of __________.

    N a. mean refraction
    N b. parallax
    N c. semidiameter
    Y d. irradiation

2843: A position obtained by applying ONLY your vessel's course and speed to a known position is a __________.

    N a. fix
    N b. running fix
    Y c. dead-reckoning position
    N d. probable position

2924: You take a bearing of 264° of a lighthouse. What bearing of another object would give the best fix?

    N a. 289°
    Y b. 350v
    N c. 081°
    N d. 120°

2998: While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 3 1/2 seconds after the signal was sounded. What is the distance to the shore?

    Y a. 640 yards
    N b. 480 yards
    N c. 315 yards
    N d. 143 yards

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

3072: ECDIS must give an alarm for which of the following cases?

    N a. When the specified limit for deviation from the planned route is exceeded
    N b. If the ship, within a specified time set by the watch officer, is going to cross a safety contour
    N c. If the ship, within a specified time set by the watch officer, is going to cross the boundary of a prohibited area
    Y d. All of the above