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 __________.


66: What will a veering wind do?


81: A buoy with a composite group-flashing light indicates a(n) __________.


105: If the GMT is 1500, the time at 75°E longitude is __________.

    N a. 1000
    N b. 1500
    N c. 1700
    Y d. 2000

117: Mean high water is the average height of __________.

    N a. the higher high waters
    N b. the lower high waters
    N c. the lower of the two daily tides
    Y d. all high waters

125: The GMT is 0445 and your zone description is +1. Your zone time is __________.

    N a. 0445
    Y b. 0345
    N c. 0545
    N d. 1545

157: Tropic tides are caused by the __________.

    Y a. Moon being at its maximum declination
    N b. Moon crossing the equator
    N c. Sun and Moon both being near 0° declination
    N d. Moon being at perigee

216: The prevailing winds in the band of latitude from approximately 5°N to 30°N are the __________.

    N a. prevailing westerlies
    Y b. northeast trade winds
    N c. southeast trade winds
    N d. doldrums

229: The shoreline on charts generally represents the mean __________.

    Y a. high water line
    N b. low water line
    N c. low water spring line
    N d. tide level

254: The range of tide is the __________.

    Y a. difference between the heights of high and low tide
    N b. distance the tide moves out from the shore
    N c. duration of time between high and low tide
    N d. maximum depth of the water at high tide

401: You are steaming in a westerly direction along the Gulf Coast. You see ahead of you a lighted buoy showing a red isophase light. Which action should you take?

    Y a. Alter course to port and leave the buoy to starboard.
    N b. Alter course to starboard and leave the buoy to port.
    N c. Alter course and leave the buoy near by on either side.
    N d. Alter course and pass the buoy well-off on either side.

412: If you were sailing in the North Pacific and were interested in the ice and iceberg limits, you could find this information in the __________.

    Y a. Pilot Chart
    N b. Coast Pilot
    N c. Notice to Mariners
    N d. None of the above

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

488: A great circle crosses the equator at 93°W. It will also cross the equator at what other longitude?

    N a. 13°E
    Y b. 87°E
    N c. 177°E
    N d. 177°W

546: If it is impossible to avoid a hurricane in the Northern Hemisphere, the most favorable place to be when the storm passes is in __________.

    N a. the dangerous semicircle
    N b. the eye (center) of the storm
    N c. that half of the storm lying to the right of the storm's path
    Y d. that half of the storm lying to the left of the storm's path

561: Buoys which mark dredging areas are painted __________.

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

668: You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133°T, and bears 042° at 105 miles from you. What is the course to steer at 10 knots to intercept vessel A?

    N a. 063°
    N b. 068°
    N c. 073°
    Y d. 079°

941: While preparing to enter a Brazilian port, you see ahead a red and green horizontally-striped buoy. The upper band is red. What action should you take?

    N a. Alter course to leave the buoy to port.
    Y b. Alter course to leave the buoy to starboard.
    N c. Pass the buoy close aboard on either side.
    N d. Pass the buoy well clear on either side.

943: You should plot your dead reckoning position __________.

    N a. when you obtain an estimated position
    N b. ONLY in piloting waters
    Y c. at every speed change
    N d. All of the above are correct.

952: What is TRUE concerning new editions of Light Lists?

    N a. Supplements to new editions are issued monthly by the U.S. Coast Guard.
    N b. New editions are published by the National Ocean Service.
    Y c. New editions are corrected through the date shown on the title page.
    N d. None of the above

961: In which country would you expect the channels to be marked with the IALA-B Buoyage System?

    Y a. Brazil
    N b. Tanzania
    N c. New Zealand
    N d. Norway

1063: When adjusting a magnetic compass using the fore-and-aft permanent magnets, you should __________.

    N a. use the magnets one at a time, putting one in one side and then one on the opposite side, one step higher.
    N b. use the magnets in pairs, starting at the top, with trays at the highest point of travel
    Y c. use the magnets in pairs, from the bottom up, with the trays at the lowest point of travel
    N d. fill all the trays with magnets, then remove them one-by-one until the deviation is removed

1072: What is the approximate geographic range of Assateague Light, VA, if your height of eye is 52 feet (15.8 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 14.1 nm
    N b. 21.8 nm
    Y c. 23.0 nm
    N d. 50.2 nm

1403: Which statement about the gyrocompass is FALSE?

    Y a. Its accuracy remains the same at all latitudes.
    N b. It seeks the true meridian.
    N c. It can be used near the Earth's magnetic poles.
    N d. If an error exists, it is the same on all headings.

1415: Planetary aberration is due, in part, to __________.

    N a. refraction of light as it enters the Earth's atmosphere
    N b. rotation of the Earth on it's axis
    Y c. the body's orbital motion during the time required for its light to reach Earth
    N d. a false horizon

1453: Indications of the master gyrocompass are sent to remote repeaters by the __________.

    N a. follow-up system
    Y b. transmitter
    N c. phantom element
    N d. azimuth motor

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

1682: Which of the listed properties does warm air possess?

    N a. It rises above cooler air and cools as it rises.
    N b. Atmospheric pressure drops as warm air rises.
    N c. Moisture in warm air condenses as the air is cooled.
    Y d. All of the above

1704: If the center of low pressure is due west of you in the Northern Hemisphere, which wind direction should you expect?

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

1738: In the Northern Hemisphere, the right half of the storm is known as the dangerous semicircle because __________.

    N a. The wind speed is greater here since the wind is traveling in the same general direction as the storm's track
    N b. the direction of the wind and seas might carry a vessel into the path of the storm
    N c. the seas are higher because of greater wind speed
    Y d. All of the above

1750: Clearance gauges at bridges indicate __________.

    N a. the height of the tide
    N b. depth of water under the bridge
    N c. charted vertical clearance at mean low water
    Y d. distance from the water to low steel of the bridge

1774: Restricted areas at locks and dams are indicated by __________.

    N a. flashing red lights upstream and fixed red lights downstream
    N b. yellow unlighted buoys
    Y c. signs and/or flashing red lights
    N d. red daymarks upstream and green daymarks downstream

1830: A vessel heading NNW is on a course of __________.

    N a. 274.5°
    N b. 292.0°
    N c. 315.5°
    Y d. 337.5°

1860: A vessel heading WSW is on a course of __________.

    N a. 202.5°
    N b. 225.0°
    Y c. 247.5°
    N d. 271.0°

1871: A lighted buoy to be left to starboard, when entering a U.S. port from seaward, shall have a __________.

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

1886: What is the relative bearing of an object dead astern?

    N a. 000°
    N b. 090°
    Y c. 180°
    N d. 270°

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

2024: In the North Sea area, you sight a buoy with a quick light showing 3 flashes every 10 seconds. Which topmark in illustration D030NG would be fitted to this buoy under the IALA Buoyage Systems? (D030NG )

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

2081: You are taking bearings on two known objects ashore. The BEST fix is obtained when the angle between the lines of position is __________.

    N a. 30°
    N b. 45°
    N c. 60°
    Y d. 90°

2099: 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.
    Y b. Continue on course until the range is closed, then alter course to the right.
    N c. Immediately alter course to the right to bring the range in line.
    N d. Immediately alter course to 309°T.

2194: 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 red ends of the magnets are forward you should lower the fore-and-aft magnets.
    N b. If the blue ends of the magnets are forward you should lower the fore-and-aft magnets.
    Y c. If the blue ends of the magnets are to port and the athwartships tray is at the bottom you should reverse the magnets.
    N d. If the blue ends of the magnets are to port and the athwartships tray is at the top you should add some magnets.

2290: Magnets in the binnacles of magnetic compasses are used to reduce the effect of __________.

    Y a. deviation
    N b. variation
    N c. local attraction
    N d. All of the above

2290: Magnets in the binnacles of magnetic compasses are used to reduce the effect of __________.

    Y a. deviation
    N b. variation
    N c. local attraction
    N d. All of the above

2375: The shortest distance between any two points on earth defines a __________.

    N a. small circle
    Y b. great circle
    N c. rhumb line
    N d. hyperbola

2414: You must construct a Mercator plotting sheet on a piece of paper measuring 20" by 28". The area includes latitude 38°S to 43°S and longitude 178°E to 175°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?

    N a. 2.6 inches
    Y b. 2.9 inches
    N c. 3.2 inches
    N d. 3.5 inches

2425: A vessel's position should be plotted using bearings of __________.

    Y a. fixed objects on shore
    N b. buoys at a distance
    N c. buoys close by
    N d. All of the above

2464: Under the IALA-A Buoyage System, when entering from seaward a lateral system buoy to be left to port may display which topmark shown? (D046NG )

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

2484: What is the equivalent of 1°53' in time units?

    N a. 3 min. 16 sec.
    N b. 5 min. 28 sec.
    N c. 6 min. 43 sec.
    Y d. 7 min. 32 sec.

2629: In both regions of the IALA buoyage system, which topmark is used on a special mark? (D022NG )

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

2638: A vessel crossing a river on the Western Rivers has the right of way over __________.

    N a. vessels ascending the river
    N b. vessels descending the river
    N c. all vessels ascending and descending the river
    Y d. None of the above

2640: In the celestial equator system of coordinates what is the equivalent to the meridians of the Earth system of coordinates?

    N a. Horizon
    Y b. Hour circles
    N c. Vertical circles
    N d. Parallel of declination

2654: What is the equivalent of 5°54' in time units?

    N a. 20 min. 16 sec.
    Y b. 23 min. 36 sec.
    N c. 25 min. 54 sec.
    N d. 30 min. 27 sec.

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

2738: While navigating in fog off a coastline of steep cliffs, you hear the echo of the ship's fog horn 3 seconds after the signal was sounded. What is the distance to the shore?

    N a. 1100 yards
    N b. 872 yards
    Y c. 550 yards
    N d. 792 yards

2739: A daymark used to indicate the starboard side of the channel when approaching from seaward will have the shape indicated by what letter in illustration D045NG?

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

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°

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

3014: Given are the courses and speeds of 4 vessels. The navigator of which vessel would be required to know the actual time of meridian transit in order to take an accurate observation at LAN?

    N a. C 356°T, Sp 5.5 knots
    Y b. C 162°T, Sp 27 knots
    N c. C 095°T, Sp 30 knots
    N d. C 268°T, Sp 22 knots

3014: Given are the courses and speeds of 4 vessels. The navigator of which vessel would be required to know the actual time of meridian transit in order to take an accurate observation at LAN?

    N a. C 356°T, Sp 5.5 knots
    Y b. C 162°T, Sp 27 knots
    N c. C 095°T, Sp 30 knots
    N d. C 268°T, Sp 22 knots

3029: On 13 November 1981 you observe a back sight of the upper 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' on the arc. The horizontal parallax is 61.3'. What is the observed altitude (Ho)?

    N a. 70°11.8'
    Y b. 69°41.8'
    N c. 69°25.6'
    N d. 69°18.4'