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.


41: Mean high water is the reference plane used for __________.


135: The standard meridian for the time zone +1 is __________.


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


168: Your vessel is making way through the water at a speed of 12 knots. Your vessel traveled 30 nautical miles in 2 hours 20 minutes. What current are you experiencing?

    N a. A following current at 2.0 knots
    N b. A head current of 2.0 knots
    Y c. A following current of 0.9 knot
    N d. A head current of 0.9 knot

217: In some parts of the world there is often a slight fall in tide during the middle of the high water period. The effect is to create a longer period of stand at higher water. This special feature is called a(n) __________.

    N a. apogean tide
    Y b. double high water
    N c. perigean tide
    N d. bore

304: In order to remove index error from a sextant, you should adjust the __________.

    N a. index mirror to make it parallel to the horizon glass with the index set at zero
    Y b. horizon glass to make it parallel to the index mirror with the index set at zero
    N c. horizon glass to make it parallel to the sextant frame
    N d. telescope to make it perpendicular to the sextant frame

307: The time meridian that is used when computing the currents for Pensacola Bay, Florida, is __________.

    N a. 60°W
    N b. 75°W
    Y c. 90°W
    N d. 105°W

312: The depth of water on a chart is indicated as 23 meters. This is equal to __________.

    N a. 11.5 fathoms
    Y b. 12.6 fathoms
    N c. 69.0 feet
    N d. 78.6 feet

351: Which buoy may be odd numbered?

    N a. A spherical buoy
    Y b. An unlighted can buoy
    N c. A red buoy
    N d. A yellow buoy

370: Prevailing winds between 30°N and 60°N latitude are from the __________.

    N a. north
    N b. south
    N c. east
    Y d. west

454: On what does the operation of an aneroid barometer depend?

    Y a. Thin, metal, air tight cell
    N b. Curved tube containing alcohol
    N c. Column of mercury supported by atmospheric pressure
    N d. Expansion of mercury in a closed tube

460: When using horizontal sextant angles of three objects to fix your position, an indeterminate position will result in which situation?

    N a. The objects lie in a straight line.
    N b. The vessel is inside of a triangle formed by the objects.
    N c. The vessel is outside of a triangle formed by the objects.
    Y d. A circle will pass through your position and the three objects.

479: You are enroute to assist vessel A. Vessel A is underway at 5 knots on course 063°T, and bears 136°T at 78 miles from you. What is the course to steer at 13 knots to intercept vessel A?

    Y a. 114°
    N b. 158°
    N c. 295°
    N d. 340°

489: You are anchored in the Aleutian Island chain and receive word that a tsunami is expected to strike the islands in six hours. What is the safest action?

    Y a. Get underway and be in deep, open-ocean water when the tsunami arrives.
    N b. Increase the scope of the anchor cable and drop the second anchor underfoot at short stay.
    N c. Get underway and be close inshore on the side of the island away from the tsunami.
    N d. Plant both anchors with about a 60° angle between them, and let out a long scope to each anchor.

540: A white buoy with an orange rectangle on it is used to indicate __________.

    N a. danger
    N b. a controlled area
    N c. an exclusion area
    Y d. general information

553: The beam width of your radar is 2°. The left tangent bearing of a small island, as observed on the PPI scope, is 056°pgc. If the gyro error is 2°E, what bearing would you plot on the chart?

    N a. 052°
    N b. 056°
    Y c. 059°
    N d. 060°

617: You are bound for the Chelsea docks in the Hudson River. The Captain wants to arrive at the docks at the first slack water on 28 July 1983. You are keeping daylight saving time. What time should you be at the docks?

    Y a. 0215
    N b. 0530
    N c. 0811
    N d. 0911

631: A light characteristic of composite group flashing indicates that there is a(n) __________.

    N a. sharp turn in the channel
    N b. narrowing in the channel at that point
    Y c. junction in the channel
    N d. obstruction that must be left to port

720: Which change in the condition of the seas could indicate the formation of a tropical storm or hurricane several hundred miles from your location?

    Y a. A long swell from an unusual direction
    N b. A lengthy lull in the wind and seas
    N c. Large seas coming from different directions
    N d. A brisk chop from the southeast

766: Which position includes the effects of wind and current?

    N a. Dead reckoning position
    N b. Leeway position
    N c. Set position
    Y d. Estimated position

804: A relative bearing is always measured from __________.

    N a. true north
    N b. magnetic north
    N c. the vessel's beam
    Y d. the vessel's head

842: Coast Pilots and navigational charts are kept corrected and up-to-date by using the __________.

    N a. pilot charts
    Y b. Notices to Mariners
    N c. Tide Tables
    N d. Current Tables

946: The wind circulation around a high pressure center in the Northern Hemisphere is __________.

    N a. counterclockwise and moving towards the high
    N b. counterclockwise and moving outward from the high
    N c. clockwise and moving towards the high
    Y d. clockwise and moving outward from the high

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

966: Most high pressure areas in the United States are accompanied by __________.

    N a. precipitation
    Y b. clear, cool weather
    N c. humid, sticky weather
    N d. cool fogs

995: What is the equivalent of 83°29.6' in time units?

    N a. 5h 47m 34.8s
    N b. 5h 18m 22.7s
    N c. 5h 01m 42.3s
    Y d. 5h 33m 58.4s

1001: While steaming in English waters on course 280°T, you sight a buoy showing a very quick-flashing (VQ) white light well to port. Maintaining course, you sight another buoy showing a quick-flashing (Q) white light. You should pass __________.

    Y a. north of the buoy
    N b. west of the buoy
    N c. east of the buoy
    N d. south of the buoy

1045: The Light List shows that a navigational light has a nominal range of 15 miles and a height above water of 40 feet (12.2 meters). Your height of eye is 25 feet (7.6 meters) and the visibility is 5 miles. At about what range will you FIRST sight the light?

    N a. 6.2 miles
    Y b. 9.5 miles
    N c. 12.9 miles
    N d. 14.2 miles

1056: The steepness of a cold front depends on __________.

    N a. the direction of wind around the front
    Y b. its velocity
    N c. the temperature of the air behind the front
    N d. the precipitation generated by the front

1081: On a voyage along the coast of France, you sight a buoy with the top marks as shown. You are required to steer __________. (D026NG )

    N a. west of the buoy
    N b. east of the buoy
    Y c. south of the buoy
    N d. north of the buoy

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

1258: You should log all barometer readings taken at sea __________.

    N a. regularly
    N b. at least once during each watch
    N c. more often under changeable weather conditions
    Y d. All of the above

1427: Determine the duration of the first PM slack water on 3 March 1983, east of the Statue of Liberty, when the current is less than 0.1 knot?

    N a. 10 minutes
    Y b. 13 minutes
    N c. 16 minutes
    N d. 19 minutes

1492: You are planning a voyage from San Francisco to Japan. Which publication contains information on the ocean routes?

    N a. Coast Pilot
    Y b. Sailing Directions (Planning Guide)
    N c. Sailing Directions (Enroute)
    N d. World Port Index

1508: A line of position is __________.

    N a. a line connecting two charted objects
    Y b. a line on some point of which the vessel may be presumed to be located
    N c. the position of your vessel
    N d. not used in a running fix

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

1524: A barometric pressure reading of 29.92 inches of mercury is equivalent to __________.

    Y a. 1013.25 millibars
    N b. 29.92 feet of water
    N c. 766 millimeters of mercury
    N d. 76 centimeters of water

1596: You are sailing south on the Intracoastal Waterway (ICW) when you sight a red nun buoy with a yellow square painted on it. Which of the following is TRUE?

    Y a. You should leave the buoy on your port hand.
    N b. This buoy marks the end of the ICW in that geographic area.
    N c. The yellow is retroreflective material used to assist in sighting the buoy at night.
    N d. The yellow square is in error and it should be a yellow triangle.

1619: Sextant A reads __________. (D043NG )

    Y a. 29°42.7'
    N b. 29°45.7'
    N c. 29°51.8'
    N d. 30°47.2'

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

1716: The hurricane season in the North Atlantic Ocean reaches its peak during the month of __________.

    N a. June
    Y b. September
    N c. November
    N d. July

1775: The letter A in illustration D006NG represents the __________.

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

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

1858: A white buoy with an orange cross within a diamond marked on it indicates __________.

    N a. danger
    Y b. vessels are excluded from the area
    N c. an anchorage area
    N d. operating restrictions are in effect

1934: The great circle of the celestial sphere that passes through the zenith, nadir, and the eastern point of the horizon is the __________.

    N a. principal vertical
    N b. hour circle
    N c. celestial meridian
    Y d. prime vertical

1934: The great circle of the celestial sphere that passes through the zenith, nadir, and the eastern point of the horizon is the __________.

    N a. principal vertical
    N b. hour circle
    N c. celestial meridian
    Y d. prime vertical

1946: When making landfall at night, you can determine if a light is a major light or an offshore buoy by __________.

    N a. the intensity of the light
    Y b. checking the period and characteristics against the Light List
    N c. the color, because the buoy will have only a red or a green light
    N d. Any of the above can be used to identify the light.

2261: You determine your vessel's position by taking a range and bearing to a buoy. Your position will be plotted as a(n) __________.

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

2277: The Light List indicates that a light has a nominal range of 20 miles and is 52 feet high. If the visibility is 12.0 miles and your height of eye is 20 feet, at what approximate distance will you sight the light?

    N a. 21.5 miles
    N b. 20.0 miles
    Y c. 13.7 miles
    N d. 12.0 miles

2288: A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?

    N a. The motion of the apparent sun is along the ecliptic.
    Y b. Measurement of time is along the celestial equator.
    N c. The speed of the Earth's revolution is not constant.
    N d. There are variations in the Earth's rotational speed.

2330: You are heading in a northerly direction when you come across an easterly current. Your vessel will __________.

    Y a. be pushed to starboard
    N b. be pushed to port
    N c. decrease in engine speed
    N d. remain on course

2486: What is the equivalent of 23 min. 20 sec. in arc units?

    N a. 16°40'
    N b. 12°32'
    N c. 9°28'
    Y d. 5°50'

2494: You must construct a Mercator plotting sheet on a piece of paper measuring 24" by 30". The area includes latitude 28°N to 35°N and longitude 175°E to 178°W. Allow a three-quarter 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 limitation?

    N a. 3.40 inches
    Y b. 3.22 inches
    N c. 3.03 inches
    N d. 2.91 inches

2502: The major factor that causes the color difference between a red star (Betelgeuse) and a blue star (Rigel) is __________.

    Y a. its surface temperature
    N b. the elevation above the horizon
    N c. the mass of the star
    N d. the contrast to nearby stars

2567: When outbound from a U.S. port, a buoy displaying a flashing red light indicates __________.

    N a. a sharp turn in the channel to the right
    N b. a wreck to be left on the vessel's starboard side
    N c. a junction with the preferred channel to the left
    Y d. the port side of the channel

2584: You must construct a Mercator plotting sheet on a piece of paper measuring 30" by 36". The area includes latitude 30°45'S to 37°15'S and longitude 004°00'E to 005°00'W. Allow a one 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 limitation?

    N a. 3.09 inches
    N b. 3.22 inches
    N c. 3.41 inches
    Y d. 3.58 inches

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

2851: You determine your vessel's position by taking a range and bearing to a buoy. Your position will be plotted as a(n) __________.

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

2859: The buoy indicated by the letter C in illustration D044NG is a __________.

    N a. nun
    N b. can
    N c. spar
    Y d. pillar

2978: Where do you find the semidiameter correction to be used to correct sextant observations of the stars?

    N a. It is included in the altitude corrections inside the front cover of the Nautical Almanac.
    N b. Table 25 in Bowditch contains the correction.
    N c. A correction of -0.5' should be applied to all star sights.
    Y d. No semidiameter correction is used.