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.


15: What is the length of a nautical mile?


130: The distance between the surface of the water and the tidal datum is the __________.


288: When using a radar in a unstabilized mode, fixes are determined most easily from __________.


296: The wind flow from the horse latitudes to the doldrums is deflected due to __________.

    Y a. Coriolis force
    N b. the mid-latitude, semi-permanent high
    N c. differing atmospheric pressures
    N d. the prevailing westerlies

301: In the U.S. Aids to Navigation System, lateral aids as seen entering from seaward will display lights with which characteristic?

    N a. Flashing
    N b. Occulting
    N c. Quick Flashing
    Y d. All of the above

325: What is the longitude of the geographical position of a body whose Greenwich hour angle is 210°30'?

    N a. 30°30'E
    N b. 59°30'W
    N c. 120°30'W
    Y d. 149°30'E

342: A polyconic projection is based on a __________.

    N a. plane tangent at one point
    N b. cylinder tangent at one parallel
    N c. cone tangent at one parallel
    Y d. series of cones tangent at selected parallels

422: If you are sailing from the East Coast of the United States to the Caribbean Sea, which publication would contain information on weather, currents, and storms?

    N a. Sailing Charts of the Caribbean Sea
    Y b. Pilot Charts of the North Atlantic
    N c. Light Lists, Atlantic and Gulf Coast
    N d. Tidal Current Tables

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

446: The usual sequence of directions in which a tropical cyclone moves in the Southern Hemisphere is __________.

    N a. northwest, west, and south
    Y b. southwest, south, and southeast
    N c. north, northwest, and east
    N d. west, northwest, and north

494: Aneroid barometers are usually calibrated to indicate atmospheric pressure in __________.

    N a. inches of mercury and centimeters
    N b. feet of mercury and millibars
    N c. inches of mercury and millimeters
    Y d. inches of mercury and millibars

573: What is the name of the movable, radial guide line used to measure direction on a radar?

    N a. Compass rose
    Y b. Cursor
    N c. Plan position indicator
    N d. Variable range marker

660: What is the length of a nautical mile?

    N a. 1,850 meters
    N b. 5,280 feet
    N c. 1,760 yards
    Y d. 6,076 feet

675: 15° of latitude is equal to __________.

    N a. 600 miles
    Y b. 900 miles
    N c. 1200 miles
    N d. 1500 miles

808: On a working copy of a weather map, a stationary front is represented by which color line?

    N a. Red
    N b. Blue
    Y c. Alternating red and blue
    N d. Purple

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

857: The current that, in many respects, is similar to the Gulf Stream is the __________.

    Y a. Kuroshio
    N b. California Current
    N c. Oyashio
    N d. Benguela Current

893: One point of a compass is equal to how many degrees?

    N a. 7.5
    Y b. 11.25
    N c. 17.5
    N d. 22.5

913: How many points are there in a compass card?

    N a. 4
    N b. 8
    N c. 24
    Y d. 32

984: The bases of middle clouds are located at altitudes of between __________.

    N a. 3,000 to 6,500 feet (914 to 1981 meters)
    Y b. 6,500 to 20,000 feet (1981 to 6096 meters)
    N c. 10,000 to 35,000 feet (3048 to 10,668 meters)
    N d. 20,000 to 60,000 feet (6096 to 18,288 meters)

1034: The expression "the air is saturated" means __________.

    Y a. the relative humidity is 100%
    N b. the vapor pressure is at its minimum for the prevailing temperature
    N c. precipitation has commenced
    N d. cloud cover is 100%

1066: The slope of a warm front is about __________.

    N a. 1 mile vertically to 10 miles horizontally
    N b. 1 mile vertically to 50 miles horizontally
    Y c. 1 mile vertically to 150 miles horizontally
    N d. 1 mile vertically to 500 miles horizontally

1104: Which condition(s) is(are) necessary for the formation of dew?

    N a. Clear skies
    N b. Calm air
    N c. Earth's surface cooler than the dew point of the air
    Y d. All of the above

1155: Which aid is NOT marked on a chart with a magenta circle?

    N a. Radar station
    Y b. Aero light
    N c. Radio beacon
    N d. Radar transponder beacon

1172: Which position shown would likely have stratus or stratocumulus clouds, occasional light drizzle, steady southerlies around 10 knots, and steady temperatures? (D049NG )

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

1221: On a chart, the characteristic of the light on a lighthouse is shown as flashing white with a red sector. The red sector __________.

    N a. indicates the limits of the navigable channel
    Y b. indicates a danger area
    N c. is used to identify the characteristics of the light
    N d. serves no significant purpose

1289: A body can only be observed at lower transit when __________.

    N a. the declination is the opposite name to the latitude
    N b. the algebraic sum of the colatitude and declination exceeds 90°
    N c. the observer is in high latitudes above either polar circle
    Y d. the body is circumpolar

1289: A body can only be observed at lower transit when __________.

    N a. the declination is the opposite name to the latitude
    N b. the algebraic sum of the colatitude and declination exceeds 90°
    N c. the observer is in high latitudes above either polar circle
    Y d. the body is circumpolar

1292: A triangular daymark would be colored __________.

    Y a. red
    N b. red and white
    N c. green
    N d. green and white

1333: If a magnetic compass is not affected by any magnetic field other than the Earth's, which statement is TRUE?

    Y a. Compass error and variation are equal.
    N b. Compass north will be true north.
    N c. Variation will equal deviation.
    N d. There will be no compass error.

1369: Which of the following is the most useful factor for predicting weather?

    N a. The present reading of the barometer
    N b. The previous reading of the barometer
    N c. The difference in the barometric readings within the past 24 hours
    Y d. The rate and direction of change of barometric readings

1450: The distance between the surface of the water and the tidal datum is the __________.

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

1545: The change in the length of day becomes greater as latitude increases because of the __________.

    N a. inclination of the diurnal circle to the equator
    N b. decreasing distance between the terrestrial meridians
    Y c. increased obliquity of the celestial sphere
    N d. changing distance between the earth and the sun

1599: The time interval between successive wave crests is called the __________.

    N a. trough
    Y b. period
    N c. frequency
    N d. epoch

1713: When a tornado moves over the water from land it is called a __________.

    N a. tornado
    Y b. waterspout
    N c. hurricane
    N d. cyclone

1885: Under the Uniform State Waterway Marking System a mooring buoy is painted __________.

    Y a. white with a blue band
    N b. yellow
    N c. any color that does not conflict with the lateral system
    N d. white with a green top

1982: In the horizon system of coordinates what is equivalent to the Greenwich hour angle of the celestial equator system?

    N a. Zenith distance
    N b. Coaltitude
    N c. Altitude
    Y d. Azimuth

2006: What is the relative bearing of an object broad on the port beam?

    N a. 315°
    N b. 300°
    Y c. 270°
    N d. 235°

2079: Permission to enter the riverward chamber of twin locks is given by the lockmaster and consists of which sound signal?

    N a. One short blast
    N b. Two short blasts
    N c. One long blast
    Y d. Two long blasts

2101: Information about major breakdowns, repairs, or other emergency operations with regard to weirs and (or) wicket dams, on the western rivers, may be obtained by consulting the __________.

    Y a. Broadcast Notice to Mariners
    N b. Light List Vol. V
    N c. U.S. Coast Pilot
    N d. All of the above

2163: The letter C in illustration D006NG represents the __________.

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

2180: Relative humidity is defined as __________.

    N a. the maximum vapor content the air is capable of holding
    N b. the minimum vapor content the air is capable of holding
    Y c. the ratio of the actual vapor content at the current temperature to the air's vapor holding capability
    N d. the relation of the moisture content of the air to barometric pressure

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

2437: When daylight savings time is kept, the times of tide and current calculations must be adjusted. One way of doing this is to __________.

    N a. add 15° to the standard meridian when calculating the time differences
    N b. apply no correction as the times at the reference stations are adjusted for daylight savings time
    Y c. add one hour to the times listed for the reference stations
    N d. subtract one hour from the times listed for the subordinate stations

2522: The letter H in illustration D006NG represents the __________. (D006NG )

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

2530: The distance between any two meridians measured along a parallel of latitude __________.

    N a. increases in north latitude and decreases in south latitude
    N b. decreases as DLO increases
    N c. increases with increased latitude
    Y d. decreases with increased latitude

2546: A structure, usually made of stone, or cement pilings, which extends from the bank at approximately right angles to the current is called a __________.

    Y a. dike
    N b. revetment
    N c. cutoff
    N d. crib

2579: A phase correction may be applicable to correct the sextant altitude correction of __________.

    N a. any star
    N b. the Sun
    N c. third magnitude stars only
    Y d. some planets

2619: In low latitudes, a first quarter Moon will always rise at about __________.

    N a. sunrise
    Y b. 1200 LMT
    N c. sunset
    N d. 2400 LMT

2639: Under the U.S. Aids to Navigation System used on the Western Rivers, aids to navigation lights on the right descending bank show __________.

    Y a. white or green lights
    N b. white or red lights
    N c. green lights only
    N d. white lights only

2646: During daylight savings time the meridian used for determining the time is located farther __________.

    Y a. east
    N b. west
    N c. east in west longitude and west in east longitude
    N d. west in west longitude and east in east longitude

2670: The angle that is measured westward from the first point of Aries to the hour circle of the body along the celestial equator is the __________.

    N a. Greenwich sidereal angle
    N b. local sidereal time
    Y c. sidereal hour angle
    N d. azimuth angle

2674: In the U.S. Aids to Navigation System on the Western Rivers, a preferred channel buoy to be left to port while proceeding downstream will __________.

    N a. have the upper band red
    N b. show a red light if lighted
    N c. have a characteristic of composite group flashing if lighted
    Y d. All of the above

2746: What is used to measure wind velocity?

    N a. Psychrometer
    N b. Barometer
    N c. Wind sock
    Y d. Anemometer

2798: A can buoy is indicated by which letter in illustration D044NG?

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

2828: The daily recurring pattern of pressure changes most noticeable in low latitudes is the __________.

    N a. daily lapse reading
    Y b. diurnal variation of pressure
    N c. pressure tendency
    N d. synoptic pressure

3007: A rotary current sets through all directions of the compass. The time it takes to complete one of these cycles, in a locale off the East coast of the US, is approximately __________.

    N a. 2 1/2 hours
    N b. 3 1/2 hours
    N c. 6 1/4 hours
    Y d. 12 1/2 hours

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

3110: While underway, automatic identification systems (AIS) broadcast all of the following information every 1 to 10 seconds EXCEPT the __________.

    N a. speed over ground
    N b. latitude and longitude
    N c. course over ground
    Y d. ship's scantlings

3126: Which of the following statements is TRUE regarding automatic identification systems (AIS)?

    N a. AIS will not provide information on another vessel if that vessel is indistinguishable in radar sea clutter.
    N b. AIS can be relied upon as the sole means to determine risk of collision and safe speed.
    N c. AIS is designed to replace ARPA, maneuvering boards, and visual bearings as a means to ascertain the risk of collision.
    Y d. AIS provides the other vessel's identity, dimensions and navigational status regardless of visibility.