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.


22: Charts showing the coast of Mexico are produced by the United States __________.


52: The reference datum used in determining the heights of land features on most charts is __________.


114: All echo-sounders can measure the __________.


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

150: An alternating light __________.

    N a. shows a light with varying lengths of the lighted period
    Y b. shows a light that changes color
    N c. marks an alternate lesser-used channel
    N d. is used as a replacement for another light

228: The Illustration shows the symbols used on radio facsimile weather charts. Which of these symbols indicates a convergence line? (D042NG )

    N a. L
    N b. F
    N c. M
    Y d. Q

259: The Illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "Q" represents a __________. (D042NG )

    N a. convergence zone
    N b. squall line
    Y c. convergence line
    N d. weather boundary

263: Loran-C uses the multiple pulse system because __________.

    N a. less signal energy is necessary for receiver operation
    Y b. more signal energy is available at the receiver
    N c. it significantly increases the peak power
    N d. it increases the signal capacity

279: As a vessel changes course to starboard, the compass card in a magnetic compass __________.

    Y a. remains aligned with compass north
    N b. also turns to starboard
    N c. first turns to starboard then counterclockwise to port
    N d. turns counterclockwise to port

300: Which of the symbols shown represents a warm front? (D018NG )

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

461: Under the U.S. Aids to Navigation System, a yellow buoy may __________.

    Y a. mark a fish net area
    N b. be lighted with a white light
    N c. show a fixed red light
    N d. All of the above

498: What is an advantage of the magnetic compass aboard vessels?

    N a. Compass error is negligible at or near the earth's magnetic poles.
    N b. It does not have to be checked as often.
    Y c. It is reliable due to it's essential simplicity.
    N d. All points on the compass rose are readily visible.

507: What will be the time after 1000 EST (ZD +5), on 4 March 1983, that the height of the tide at City Island, NY, will be 2.4 feet?

    Y a. 1228
    N b. 1240
    N c. 1244
    N d. 1248

663: You are underway at 10 knots. At 1800 you note a radar contact dead ahead at a range of 10 miles. At 1812 the contact is dead ahead at a range of 8 miles. The estimated speed of the contact is __________.

    Y a. dead in the water
    N b. 5 knots
    N c. 10 knots
    N d. 15 knots

671: You sight a buoy fitted with a double-sphere topmark. If sighted at night, this buoy would show a __________.

    N a. quick-flashing red light
    N b. quick-flashing green light
    Y c. flashing white light showing a group of two flashes
    N d. flashing red light showing a group of three flashes

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

815: When entering from seaward, a buoy displaying a composite group (2+1) flashing red light indicates __________.

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

905: The Sun's center is coincident with the principal vertical circle when __________.

    Y a. in lower transit
    N b. the hour circle and prime vertical are coincident
    N c. the declination is zero degrees and the azimuth is exactly N 135°E
    N d. the declination is zero degrees and the azimuth is exactly N 135°W

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.

979: Which kind of conditions would you observe as the eye of a storm passes over your vessel's position?

    Y a. Huge waves approaching from all directions, clearing skies, light winds, and an extremely low barometer
    N b. Flat calm seas, heavy rain, light winds, and an extremely low barometer
    N c. Flat calm seas, heavy rain, light winds, and high pressure
    N d. Huge waves approaching from all directions, clearing skies, light winds, and high pressure

1028: At what angle to the isobars do surface winds blow over the open sea?

    N a. About 90°
    N b. About 50°
    N c. About 25°
    Y d. About 15°

1029: Which would be the subject of a NAVAREA warning?

    N a. A drifting buoy sighted in mid-ocean
    N b. Extinguishment of Wolf Trap Light located inside Chesapeake Bay
    N c. All military exercises on the high seas involving four or more vessels
    Y d. Off-air times of radio beacons when scheduled for routine maintenance

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

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

1113: A single vertical magnet placed underneath the compass in the binnacle is used to compensate for __________.

    N a. the horizontal component of the permanent magnetism
    Y b. deviation caused by the vessel's inclination from the vertical
    N c. induced magnetism in the horizontal soft iron
    N d. induced magnetism in the vertical soft iron

1183: The principal purpose of magnetic compass adjustment is to __________.

    N a. reduce the variation as much as possible
    Y b. reduce the deviation as much as possible
    N c. reduce the magnetic dip as much as possible
    N d. allow the compass bowl to swing freely on its gimbals

1200: You want to transit Pollock Rip Channel, MA, on 6 April 1983. What is the period of time around the 0955 (ZD +5) slack in which the current does not exceed 0.3 knot?

    N a. 0911 to 0955
    N b. 0940 to 1010
    N c. 0955 to 1044
    Y d. 0935 to 1017

1209: You are on course 201°T. To check the speed of your vessel you should observe a celestial body on which bearing?

    N a. 090°
    N b. 111°
    N c. 180°
    Y d. 201°

1235: Weather information provided by the National Weather Service (NWS) advisories should be used along with __________.

    N a. the Tide Tables and Tidal Current Tables
    N b. the local Notice to Mariners
    Y c. weather maps and local knowledge
    N d. any U.S. Coast Pilot

1245: You can follow the approach of a dangerous cyclonic storm by inspecting __________.

    Y a. a newspaper, a weather map, a weather fax, or a weather forecast
    N b. the National Weather Service Observing Handbook No.1, Marine Surface Observations
    N c. the Coast Pilot or Sailing Directions
    N d. the sky overhead

1322: What will be the velocity of the tidal current at Grant's Tomb, 123rd Street, NY, NY, at 1412 EST (ZD +5) on 22 March 1983?

    N a. 0.5 knot
    N b. 0.8 knot
    Y c. 1.1 knots
    N d. 1.3 knots

1337: What will be the time of maximum flood current at Sagamore Bridge on the Cape Cod Canal during the morning of 6 December 1983 (ZD +5)?

    Y a. 0708
    N b. 0712
    N c. 0716
    N d. 1020

1381: Geographic range is the maximum distance at which a light may be seen under __________.

    N a. existing visibility conditions, limited only by the curvature of the Earth
    Y b. perfect visibility conditions, limited only by the curvature of the Earth
    N c. existing visibility conditions, limited only by the intensity of the light
    N d. perfect visibility conditions, limited only by interference from background lighting

1465: The planet Venus can be observed in the morning before sunrise if it is well to the __________.

    Y a. west of and higher than the Sun
    N b. west of and lower than the Sun
    N c. east of and higher than the Sun
    N d. east of and lower than the Sun

1480: What is the definition of height of tide?

    N a. The vertical difference between the heights of low and high water
    N b. The vertical difference between a datum plane and the ocean bottom
    N c. The vertical distance from the surface of the water to the ocean floor
    Y d. The vertical distance from the tidal datum to the level of the water at any time

1521: To avoid error you should read the scale of an aneroid barometer with your eye placed __________.

    N a. to the right of the pointer
    N b. to the left of the pointer
    Y c. directly in front of the pointer
    N d. slightly above the meniscus

1537: Which sextant in illustration D043NG reads 29°47.5'? (D043NG )

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

1548: The Illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "K" represents a __________. (D042NG )

    Y a. hurricane
    N b. thunderstorm
    N c. convergence zone
    N d. convergence line

1583: The angle measured from the observer's meridian, clockwise or counterclockwise up to 180°, to the vertical circle of the body is the __________.

    N a. local hour angle
    Y b. azimuth angle
    N c. meridian angle
    N d. observer's longitude

1590: Civil twilight starts at 1812 zone time on 26 August 1981, Your DR position at that time is LAT 21°06'S, LONG 14°56' W. Which statement concerning the planets available for evening sights is TRUE?

    N a. Mars will be near the prime vertical in the eastern sky.
    Y b. Venus may be identified from Saturn and Jupiter because it is the brightest.
    N c. Sights of Venus, Jupiter, and Saturn will yield a good three line fix.
    N d. A sight of either Jupiter, Saturn, or Venus will give a latitude line.

1737: You can determine if your vessel's position is in the dangerous or navigable semicircle of a hurricane by __________.

    N a. observing whether the wind is veering or backing
    N b. plotting two or more recent storm positions from weather bulletins
    Y c. Both A and B
    N d. Neither A nor B

1828: When entering from seaward, a buoy displaying a single-flashing red light indicates __________.

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

1888: What is the relative bearing of an object broad on the starboard bow?

    N a. 030°
    Y b. 045°
    N c. 060°
    N d. 075°

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

2078: If a towboat requires a double lockage it shall give which sound signal at a distance of not more than one mile from the lock?

    N a. One short blast followed by two long blasts
    N b. One long blast followed by one short blast
    N c. Two long blasts followed by one short blast
    Y d. One long blast followed by two short blasts

2167: 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 B if the lock walls and piers are not awash?

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

2171: 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 B if the lock walls and piers are not awash?

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

2215: You are required to enter a lock on your voyage. Information on the lock regulations, signals, and radio communications can be found in __________.

    N a. the publication "Key to the Locks"
    N b. Bowditch
    N c. Corps of Engineers Information Bulletin
    Y d. Coast Pilot

2271: What is the definition of height of tide?

    N a. The vertical distance from the surface of the water to the ocean floor
    Y b. The vertical distance from the tidal datum to the level of the water at any time
    N c. The vertical difference between a datum plane and the ocean bottom
    N d. The vertical difference between the heights of low and high water

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.

2574: What is the equivalent of 2°52' in time units?

    N a. 9 min. 23 sec.
    Y b. 11 min. 28 sec.
    N c. 11 min. 56 sec.
    N d. 12 min. 18 sec.

2777: A sailing chart could have a scale of __________.

    N a. not more than 1:25,000
    N b. 1:35,000
    N c. 1:100,000
    Y d. 1:700,000

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°

2821: The height of tide is the __________.

    N a. difference between the depth of the water at high tide and the depth of the water at low tide
    N b. depth of water at a specific time due to tidal effect
    Y c. difference between the depth of the water and the area's tidal datum
    N d. difference between the depth of the water and the high water tidal level

2902: The direction a vessel is pointed at any given time is the __________.

    N a. course
    N b. track
    Y c. heading
    N d. course over the ground

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

3040: Which instrument is used to predict the approach of a low pressure system?

    N a. Anemometer
    N b. Fathometer
    Y c. Barometer
    N d. Thermometer

3041: The letter H in illustration D006NG represents the __________.

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

3067: Which of the following are data layer categories to be displayed on ECDIS?

    N a. ECDIS warnings and messages
    N b. Hydrographic Office data
    N c. Notice to Mariners information
    Y d. All of the above

3120: The short text messaging feature of the automatic identification system (AIS) allows for messages of up to___.

    N a. 56 characters
    N b. 64 characters
    N c. 128 characters
    Y d. 158 characters