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.


13: Most modern Loran-C receivers, when not tracking properly, have a(n) __________.


37: What does the term "tide" refer to?


39: Civil twilight begins at 1910 zone time on 20 July 1981. Your DR position at that time is LAT 22°16'N, LONG 150°06'W. Which statement concerning the planets available for evening sights is TRUE?


77: When there are small differences between the heights of two successive high tides or two low tides, in a tidal day, the tides are called __________.

    N a. diurnal
    Y b. semidiurnal
    N c. solar
    N d. mixed

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

115: The date is the same all over the world at __________.

    N a. 0000 GMT
    Y b. 1200 GMT
    N c. 0000 LMT for an observer at 90°E longitude
    N d. no time

148: When possible, a DR plot should always be started from where?

    N a. Any position
    Y b. A known position
    N c. An assumed position
    N d. None of the above

178: You are steering a southerly course, and you note that the chart predicts an easterly current. Without considering wind, how may you allow for the set?

    Y a. Head your vessel slightly to the right
    N b. Head your vessel slightly to the left
    N c. Decrease your speed
    N d. Increase your speed

186: In the doldrums you will NOT have __________.

    N a. high relative humidity
    N b. frequent showers and thunderstorms
    Y c. steep pressure gradients
    N d. frequent calms

220: At 0000 you fix your position and plot a new DR track line. At 0200 you again fix your position and it is 0.5 mile east of your DR. Which statement is TRUE?

    N a. The current is westerly at 0.5 knot.
    N b. You must increase speed to compensate for the current.
    N c. The current cannot be determined.
    Y d. The drift is 0.25 knot.

235: When the equation of time is taken from the Nautical Almanac for use in celestial navigation, it is used to determine __________.

    N a. zone time
    N b. sunrise
    Y c. time of local apparent noon
    N d. local mean time

247: Neap tides occur __________.

    N a. at the start of spring, when the Sun is nearly over the equator
    N b. only when the Sun and Moon are on the same sides of the Earth and are nearly in line
    Y c. when the Sun and Moon are at approximately 90° to each other, as seen from the Earth
    N d. when the Sun, Moon, and Earth are nearly in line, regardless of alignment order

258: You are enroute to Savannah, GA, from Recife, Brazil. There is a strong N'ly wind blowing. As you cross the axis of the Gulf Stream you would expect to encounter __________.

    N a. cirrus clouds
    N b. long swells
    N c. smoother seas and warmer water
    Y d. steeper waves, closer together

283: Loran-C operates on a single frequency centered on __________.

    Y a. 100 kHz
    N b. 500 kHz
    N c. 1,850 kHz
    N d. 1,950 kHz

290: The true wind is from 330°T, speed 6 knots. You want the apparent wind to be 30 knots from 10° on your port bow. To what course and speed must you change?

    N a. Cn 240°, 28.0 knots
    N b. Cn 270°, 28.0 knots
    N c. Cn 180°, 30.0 knots
    Y d. Cn 090°, 32.5 knots

337: To predict the actual depth of water using the Tide Tables, the number obtained from the Tide Tables is __________.

    N a. the actual depth
    Y b. added to or subtracted from the charted depth
    N c. multiplied by the charted depth
    N d. divided by the charted depth

442: In very high latitudes, the most practical chart projection is the __________.

    N a. Mercator
    N b. gnomonic
    N c. azimuthal
    Y d. Lambert conformal

496: Severe tropical cyclones (hurricanes, typhoons) occur in all warm-water oceans except the __________.

    N a. Indian Ocean
    N b. North Pacific Ocean
    N c. South Pacific Ocean
    Y d. South Atlantic Ocean

512: On a gnomonic chart, a great circle track between Los Angeles and Brisbane will appear as a __________.

    N a. loxodromic curve
    N b. curved line concave to the equator
    Y c. straight line
    N d. spiral approaching the poles as a limit

514: What instrument measures wind velocity?

    N a. Hydrometer
    N b. Barometer
    N c. Psychrometer
    Y d. Anemometer

587: Your vessel has a draft of 34 feet. On 8 October 1983 you wish to pass over an obstruction near Jaffrey Point, NH, that has a charted depth of 31 feet. Allowing for a safety margin of 3 feet, what is the earliest time after 0900 DST (ZD +4) that this passage can be made?

    N a. 0920
    Y b. 1029
    N c. 1120
    N d. 1159

724: Which statement concerning GPS is TRUE?

    N a. It cannot be used in all parts of the world.
    N b. There are 12 functioning GPS satellites at present.
    Y c. It may be suspended without warning.
    N d. Two position lines are used to give a 2D fix.

785: An amplitude of the Sun in high latitudes __________.

    N a. is most accurate before sunrise
    N b. is most accurate after sunset
    N c. should only be observed when the Sun's lower limb is above the horizon
    Y d. is most accurate when the Sun's center is observed on the visible horizon

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

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

848: It is unlawful to approach within how many yards of a northern right whale?

    N a. 200
    N b. 300
    N c. 400
    Y d. 500

908: From LAT 07°12'N, LONG 80°00'W, to LAT 47°12'S, LONG 169°18'E, the initial great circle course angle is 137.25°. How would you name this course?

    N a. N 137.25°E
    N b. S 137.25°E
    Y c. N 137.25°W
    N d. S 137.25°W

933: How many degrees are there on a compass card?

    Y a. 360°
    N b. 380°
    N c. 390°
    N d. 420°

1084: As the temperature of an air mass decreases, the __________.

    N a. absolute humidity decreases
    Y b. relative humidity increases
    N c. specific humidity decreases
    N d. dew point rises

1192: You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033°T, and bears 284°T at 43 miles from you. What is the course to steer at 16 knots to intercept vessel A?

    N a. 284°
    Y b. 303°
    N c. 329°
    N d. 342°

1238: What will be the height of tide at Three Mile Harbor Entrance, Gardiners Bay, NY, at 0700 (ZD +5) on 14 Nov 1983?

    N a. 1.1 feet (0.3 meters)
    Y b. 1.7 feet (0.5 meters)
    N c. 1.9 feet (0.6 meters)
    N d. 2.2 feet (0.7 meters)

1300: You are approaching a sea buoy which emits a racon signal. This signal is triggered by which type of radar?

    Y a. 3 cm
    N b. 10 cm
    N c. Both 3 cm and 10 cm
    N d. Signal does not depend on radar type.

1315: What is a lighted safe water mark fitted with to aid in its identification?

    N a. Red and white retroreflective material
    N b. A sequential number
    Y c. A spherical topmark
    N d. A red and white octagon

1367: You want to transit Hell Gate, NY on 23 July 1983. What is the period of time around the AM (ZD +4) slack before ebb when the current will be less than 0.3 knot?

    N a. 0939 to 0957
    Y b. 0943 to 0953
    N c. 0844 to 0852
    N d. 0348 to 0356

1401: The maximum distance at which a light may be seen under existing visibility conditions is called __________.

    N a. nominal range
    Y b. luminous range
    N c. charted range
    N d. geographic range

1469: The charted channel depth at Eastport, ME, is 28 feet. You are drawing 31.5 feet and wish 2 feet clearance under the keel. What is the earliest time after 1700 (ZD +4) on 6 September 1983 that you can enter the channel?

    N a. 1825
    N b. 1903
    Y c. 1915
    N d. 2003

1535: When observing a rapid rise in barometric pressure, you may expect __________.

    N a. clear weather with no wind, but the possibility of rain or snow within 24 hours
    N b. deteriorating weather with rain or snow
    N c. heavy rain or severe thundershowers
    Y d. clearing weather, possibly accompanied by high winds

1611: What indicates a dual purpose buoy?

    N a. Red buoy with a horizontal yellow band
    N b. Red and white vertically-striped buoy with a vertical yellow stripe
    N c. Red and white vertically-striped buoy with a red spherical topmark
    Y d. Green buoy with a yellow square

1632: Lighted white and orange buoys must show which color light?

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

1642: Which type of cloud formation should be of immediate concern to small craft operators?

    N a. cirrus
    N b. altostratus
    N c. nimbostratus
    Y d. cumulonimbus

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

1736: Which statement is FALSE concerning the dangerous semicircle of a hurricane?

    N a. The actual wind speed is increased by the forward movement of the storm along its track
    N b. the direction of the wind and the sea might carry a vessel directly into the storm's path
    N c. The seas are higher
    Y d. The rain is heavier

1882: The GP of a body for a high altitude sight is determined from the Greenwich hour angle and the __________.

    N a. circle of equal altitude
    N b. zenith distance
    N c. azimuth angle
    Y d. declination

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

1984: When a dual purpose marking is used, the mariner following the Intracoastal Waterway should be guided by the __________.

    N a. color of the aid
    N b. shape of the aid
    N c. color of the top band
    Y d. shape of the yellow mark

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

2134: The Moon and Sun are in line over your meridian. Tomorrow when the Sun is over your meridian, the Moon will be __________.

    N a. over the meridian too
    Y b. about 12°East of the meridian
    N c. about 6°West of the meridian
    N d. about 11° west of the meridian

2212: Which information is found in the chart title?

    N a. Number of the chart
    N b. Edition date
    N c. Variation information
    Y d. Survey information

2264: The revision date of a chart is printed on which area of the chart?

    N a. Top center
    Y b. Lower-left corner
    N c. Part of the chart title
    N d. Any clear area around the neat line

2363: As shown, the position labeled C was plotted because __________. (D051NG )

    N a. the vessel's speed changed
    N b. the vessel's course changed form due North to due East
    Y c. running fixes are better estimates of true position than dead-reckoning positions
    N d. All of the above are correct

2366: The major problem with Moon sights is the __________.

    N a. rapid changes in GHA and declination introduce errors into the calculations
    Y b. lack of a well defined limb during certain phases and positions in the sky
    N c. approximations used in the solution caused by the variable horizontal parallax
    N d. augmentation effect caused by the relatively short distance to the Moon

2468: Under the U.S. Aids to Navigation System on the Western Rivers, the buoys marking the starboard side of the channel when going upstream will be __________.

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

2492: A star that suddenly becomes several magnitudes brighter and then gradually fades is a __________.

    N a. double star
    N b. variable star
    Y c. nova
    N d. nebula

2800: Where is the pivot point of a towboat with a tow ahead?

    N a. One-third the length of the combined unit forward of the towboat
    Y b. One-third the length of the combined unit back from the head
    N c. At the head of the towboat
    N d. One-half the length of the combined unit

2805: You are entering port and have been instructed to anchor, as your berth is not yet available. You are on a SW'ly heading, preparing to drop anchor, when you observe the range as shown on your starboard beam. You should __________. (D047NG )

    N a. drop the anchor immediately as the range lights mark an area free of obstructions
    N b. drop the anchor immediately as a change in the position of the range lights will be an indication of dragging anchor
    N c. NOT drop the anchor until the lights are in line
    Y d. ensure your ship will NOT block the channel or obstruct the range while at anchor

2832: The Light List indicates that a dayboard is a type MR. You should __________.

    Y a. leave it on either side
    N b. look for the other dayboard forming the range
    N c. look for an all red daymark
    N d. check to enter the correct channel at this junction daymark

2858: While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 2 1/2 seconds after the signal was sounded. What is the distance to the shore?

    N a. 225 yards
    Y b. 460 yards
    N c. 750 yards
    N d. 910 yards

2868: 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. Which action should you take? (D048NG )

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

2904: Your radar displays your ship off center. As you proceed on your course, your ship's marker moves on the PPI scope while echoes from land masses remain stationary. What is this display called?

    N a. Off center
    Y b. True motion
    N c. Stabilized
    N d. Head up

2980: What volume of the Coast Guard Light List is used for the Mississippi River system?

    N a. I
    N b. II
    N c. IV
    Y d. V

3013: A white buoy with an orange rectangle on it displays __________.

    Y a. directions
    N b. dangers
    N c. exclusion areas
    N d. All of the above