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.


68: A position obtained by taking lines of position from one object at different times and advancing them to a common time is a(n) __________.


138: The path that a vessel is expected to follow, represented on a chart by a line drawn from the point of departure to the point of arrival, is the __________.


151: Under the U.S. Aids to Navigation System, spherical buoys may be __________.


158: Discounting slip, if your vessel is turning RPM for 10 knots and making good a speed of 10 knots, the current could be __________.

    N a. with you at 10 knots
    N b. against you at 10 knots
    Y c. slack
    N d. with you at 2 knots

185: A ship is in longitude 54°00'W on a true course of 270°. The ship's clocks are on the proper time zone. At what longitude should the clocks be changed to maintain the proper zone time?

    N a. 45°00'W
    N b. 52°30'W
    N c. 60°00'W
    Y d. 67°30'W

265: It is 1200 local time for an observer at 54°E longitude. Which statement is TRUE?

    N a. It is afternoon at Greenwich.
    N b. It is midnight at 126°E longitude.
    Y c. The observer is in time zone -4.
    N d. All of the above are true.

275: Which statement concerning illustration is correct? (Soundings and heights are in meters) (D010NG )

    Y a. The sunken wreck southwest of Beito Island shows the hull or superstructure above the sounding datum.
    N b. There is a 12-meter deep hole inside the 5-meter curve just west of Beito Island.
    N c. The position of the lightship is indicated by the center of the star on the symbol's mast.
    N d. Maury Lightship swings about her anchor on a circle with a 21-meter diameter.

284: The marine sextant is subject to seven different types of errors, four of which may be corrected by the navigator. An error NOT correctable by the navigator is __________.

    N a. index error
    Y b. prismatic error
    N c. perpendicularity of the horizon glass
    N d. perpendicularity of the index mirror

293: The use of pulse groups and extremely precise timing at each Loran-C station makes possible the use of __________.

    N a. high frequency pulses
    N b. combinations of high and low frequency pulses
    Y c. the same frequency for all stations in a chain
    N d. varied long and short pulses

328: The direction of prevailing winds in the Northern hemisphere is caused by the __________.

    N a. magnetic field at the North Pole
    N b. Gulf Stream
    Y c. Earth's rotation
    N d. Arctic cold fronts

341: Buoys which only mark the left or right side of the channel will never exhibit a light with which characteristic?

    N a. Flashing
    N b. Quick flashing
    Y c. Composite group flashing
    N d. Equal interval (isophase)

420: 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 )

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

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

469: Where are the prevailing westerlies of the Southern Hemisphere located?

    N a. Between the Equator and 10° latitude
    N b. Between 10° and 20° latitude
    Y c. Between 30° and 60° latitude
    N d. Between 60° and 90° latitude

499: Which of the symbols shown represents an occluded front? (D018NG )

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

558: A buoy bears 176°T at 3000 yards. What is the course to make good to leave the buoy 100 yards to starboard?

    Y a. 174°T
    N b. 176°T
    N c. 178°T
    N d. 180°T

619: According to Buys Ballot's Law, when an observer in the Southern Hemisphere experiences a northwest wind, the center of the low pressure is located to the __________.

    N a. east-northeast
    Y b. south-southwest
    N c. east-southeast
    N d. west-southwest

683: A radar contact will remain stationary on a relative motion radar display only when it is __________.

    N a. on the same course as your vessel
    N b. at the same speed as your vessel
    Y c. on the same course and speed as your vessel
    N d. on a reciprocal course at the same speed as your vessel

686: The pressure gradient between the horse latitudes and doldrums runs __________.

    N a. east to west
    Y b. north to south
    N c. northeast to southwest
    N d. northwest to southeast

737: What describes an ebb current?

    N a. Horizontal movement of the water away from the land following low tide
    N b. Horizontal movement of the water toward the land following low tide
    Y c. Horizontal movement of the water away from the land following high tide
    N d. Horizontal movement of the water toward the land following high tide

768: The wind velocity is higher in the dangerous semicircle of a tropical cyclone because of the __________.

    Y a. wind circulation and forward motion of the storm
    N b. extension of the low pressure ridge
    N c. recurvature effect
    N d. direction of circulation and pressure gradient

775: A sidereal day is shorter than a solar day. This difference is due to __________.

    N a. irregularities in the daily rotational rate of the Sun
    N b. the space motion of the solar system
    N c. the precession of the equinoxes
    Y d. the use of different reference points

786: The greater the pressure difference between a high and a low pressure center, the __________.

    N a. dryer the air mass will be
    N b. cooler the temperature will be
    Y c. greater the force of the wind will be
    N d. warmer the temperature will be

799: 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. green can buoy
    N b. red can buoy
    Y c. green conical buoy
    N d. red conical buoy

809: The compass rose on a nautical chart indicates both variation and __________.

    N a. deviation
    Y b. annual rate of variation change
    N c. precession
    N d. compass error

885: The daily path of a celestial body that is parallel to the celestial equator is the __________.

    N a. altitude circle
    N b. vertical circle
    Y c. diurnal circle
    N d. hour circle

885: The daily path of a celestial body that is parallel to the celestial equator is the __________.

    N a. altitude circle
    N b. vertical circle
    Y c. diurnal circle
    N d. hour circle

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

945: What is NOT a side of the navigational triangle used in sight reduction?

    Y a. Altitude
    N b. Zenith distance
    N c. Colatitude
    N d. Polar distance

965: In order for a star to be used for a sight at lower transit, the star must __________.

    Y a. be circumpolar
    N b. have a declination equal to or greater than your latitude
    N c. have a GHA of 180°
    N d. have the SHA equal to or less than the LHA

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

    N a. path of the ecliptic relative to the equator
    N b. decreasing distance between meridians
    N c. changing distance between the Earth and the Sun
    Y d. increased obliquity of the Sun's diurnal circle

992: Which publication contains information on Naval Control of Shipping (NCS) in time of emergency or war?

    Y a. Pub. 117, Radio Navigational Aids
    N b. Appropriate volume of the Sailing Directions
    N c. Pub. 102, International Code of Signals
    N d. Light List

1050: The passing of a low pressure system can be determined by periodically checking the __________.

    N a. thermometer
    N b. hygrometer
    Y c. barometer
    N d. anemometer

1064: The dew point temperature is __________.

    N a. always higher than the air temperature
    N b. always lower than the air temperature
    N c. equal to the difference between the wet and dry bulb temperatures
    Y d. the temperature at which the air is saturated with water vapor

1108: Preferred channel buoys indicate the preferred channel to transit by __________.

    N a. odd or even numbers
    Y b. the color of their top band
    N c. the location of the buoy in the channel junction
    N d. the buoy's light rhythms

1157: How many slack tidal currents usually occur each day on the east coast of the United States?

    N a. One
    N b. Two
    N c. Three
    Y d. Four

1188: The magnitude of three stars is indicated. Which star is the brightest?

    N a. Antares + 1.2
    N b. Altair + 0.9
    Y c. Vega + 0.1
    N d. Cannot be determined; magnitude indicates size not brightness

1239: While taking weather observations, you determine that the wind is blowing from the northeast. You would record the wind direction in the weather log as __________.

    Y a. 045°
    N b. 090°
    N c. 135°
    N d. 225°

1259: General information on enroute weather and climate is found in __________.

    Y a. the Sailing Directions and the Coast Pilot
    N b. a weather fax
    N c. the Local Notice to Mariners
    N d. the Light List

1358: Despite weather predictions for continued good weather, a prudent mariner should be alert for all of the following, EXCEPT a sudden __________.

    N a. drop in barometric pressure
    Y b. drop in temperature
    N c. wind shift
    N d. squall line

1429: A celestial body will cross the prime vertical circle when the latitude is numerically __________.

    Y a. greater than the declination and both are of the same name
    N b. less than the declination and both are of the same name
    N c. greater than the declination and both are of contrary name
    N d. less than the declination and both are of contrary name

1539: You are steaming in the open ocean of the North Pacific between the Aleutian Chain and Hawaii. A warning broadcast indicates that an earthquake has occurred in the Aleutians and has generated a tsunami that is predicted to hit Hawaii. What action is necessary for the ship's safety?

    N a. Calculate the tsunami's ETA at your position and turn to a course that will head into the Tsunami.
    N b. Securely stow all loose gear, check deck lashings, and prepare for extreme rolls.
    Y c. No special action as tsunamis are inconspicuous in the open ocean
    N d. Prepare for sudden, high-velocity wind gusts from rapidly changing directions.

1657: Fog is formed when __________.

    N a. the moisture in the air is condensed into small droplets
    N b. air is cooled to its dew point
    N c. the base of a cloud is on the ground
    Y d. All of the above

1784: If your vessel were proceeding down river (descending), a green square marker with a green reflector border on the right bank would be a __________.

    N a. mile board
    N b. dredging mark
    Y c. passing daymark
    N d. crossing daymark

1804: Magnetic information on a chart may be __________.

    N a. found in the center(s) of the compass rose(s)
    N b. indicated by isogonic lines
    N c. found in a note on the chart
    Y d. All of the above

1807: Which weather system produces strong cold winds called "Northers" during the winter months in the Gulf of Mexico?

    N a. A polar maritime air mass
    Y b. A high pressure system
    N c. A cyclone
    N d. A low pressure system

1926: The prime vertical is the great circle on the celestial sphere that passes through the __________.

    N a. celestial poles and the zenith
    Y b. zenith, nadir and the east point of the horizon
    N c. celestial poles and the celestial body
    N d. zenith, nadir and celestial body

1936: The parallel of latitude at 66°33'N is the __________.

    N a. Tropic of Cancer
    N b. Tropic of Capricorn
    Y c. Arctic Circle
    N d. ecliptic

1942: In the horizon system of coordinates what is equivalent to the declination of the equator system?

    N a. Nadir
    N b. Azimuth angle
    Y c. Altitude
    N d. Zenith distance

2056: This illustration represents a fixed C of E lock and dam. What navigational light(s) is(are) exhibited at the position indicated by the letter C? (D038NG )

    N a. One red light
    Y b. Two green lights
    N c. Three green lights
    N d. No lights

2165: 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 B if the lock walls and piers are not awash? (D037NG )

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

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

2181: Diagram Number D037NG 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?

    Y a. One red light
    N b. Two red lights
    N c. Three red lights
    N d. No lights

2314: A vessel is heading magnetic east and its magnetic compass indicates a heading of 086°. What action should be taken to remove this error during compass adjustment?

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

2340: What is a "Special Warning"?

    N a. An urgent message concerning a vessel in distress
    N b. A weather advisory about unusual meteorological or oceanographic phenomena hazardous to vessels
    Y c. A broadcast disseminating an official government proclamation affecting shipping
    N d. A radio navigational warning concerning a particularly hazardous condition affecting navigation

2396: Perihelion is the point where the Sun __________.

    Y a. is nearest to the Earth
    N b. is farthest from the Earth
    N c. is on the opposite side of the Earth from the Moon
    N d. and Moon and Earth are in line

2440: You are on course 357°T and take a relative bearing of a lighthouse of 180°. What is the true bearing to the lighthouse?

    N a. 003°
    N b. 227°
    Y c. 177°
    N d. 363°

2729: While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 5.5 seconds after the signal was sounded. What is the distance to the shore?

    N a. 3825 ft (1166 meters)
    N b. 3450 ft (1052 meters)
    Y c. 3072 ft (936 meters)
    N d. 2475 ft (754 meters)

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

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