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.


64: Mean lower low water is the reference plane used for __________.


126: A katabatic wind blows __________.


207: An important lunar cycle affecting the tidal cycle is called the nodal period. How long is this cycle?


285: The apparent wind is zero when the true wind is __________.

    N a. zero
    N b. from ahead and equal to the ship's speed
    Y c. from astern and equal to the ship's speed
    N d. from astern and is twice the ship's speed

329: The symbols shown are used on radio facsimile weather charts. Which symbol indicates a weather boundary? (D042NG )

    N a. I
    N b. H
    N c. G
    Y d. F

334: The index error is determined by adjusting the __________.

    N a. sextant frame
    N b. horizon glass
    N c. index mirror
    Y d. micrometer drum

335: What is the geographic longitude of a body whose GHA is 232°27'?

    Y a. 127°33'E
    N b. 52°27'E
    N c. 61°52'W
    N d. 61°52'E

395: If the Sun's observed altitude is 27°12', the zenith distance is __________.

    Y a. 62°48'
    N b. 27°12'
    N c. 152°48'
    N d. 43°12'

419: The ocean bottom that extends from the shoreline out to an area where there is a marked change in slope to a greater depth is the __________.

    N a. abyssal plain
    Y b. continental shelf
    N c. borderland
    N d. offshore terrace

434: The purpose of the "set" hand on an aneroid barometer is to __________.

    N a. adjust the barometer
    Y b. indicate any change in the reading of the barometer
    N c. provide a correction for height above sea level
    N d. provide a correction for temperature changes

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

501: Which of the buoys listed below could be used to mark an anchorage?

    N a. White buoy numbered "3"
    N b. White buoy with a green top
    N c. White buoy with orange bands
    Y d. Yellow buoy lettered "N"

624: When using a mechanical (windup type) marine chronometer, how often should it be reset?

    Y a. Only when it is overhauled
    N b. Whenever the chronometer error exceeds approximately four minutes
    N c. At the start of each voyage
    N d. If the chronometer rate changes from gaining to losing or vice versa

637: Your draft is 24 feet. You wish to pass over an obstruction near Lovell Island, MA, on 6 May 1983. The charted depth is 22 feet. Allowing a safety margin of 3.0 feet, what is the earliest time after 0200 DST (ZD +4) that this passage can be made?

    N a. 0215
    N b. 0245
    N c. 0310
    Y d. 0347

666: In the Northern Hemisphere, your vessel is believed to be in the direct path of a hurricane, and plenty of sea room is available. The best course of action is to bring the wind on the __________.

    N a. starboard bow, note the course, and head in that direction
    Y b. starboard quarter, note the course, and head in that direction
    N c. port quarter, note the course, and head in that direction
    N d. port bow, note the course, and head in that direction

824: An "atoll cloud" forming over an island due to heating of the land during the daytime would be which type?

    N a. Cirrus
    Y b. Cumulus
    N c. Stratus
    N d. Nimbus

866: Anticyclones are usually characterized by __________.

    Y a. dry, fair weather
    N b. high winds and cloudiness
    N c. gustiness and continuous precipitation
    N d. overcast skies

888: Recurvature of a hurricane's track usually results in the forward speed __________.

    Y a. increasing
    N b. decreasing
    N c. remaining the same
    N d. varying during the day

998: The navigable semicircle of a tropical storm in the South Indian Ocean is located on which side of the storm's track?

    N a. Rear
    N b. Front
    N c. Left
    Y d. Right

1088: Which statement about an estimated position is TRUE?

    N a. It is more reliable than a fix based on radar bearings.
    Y b. It may be based on a single LOP or questionable data.
    N c. When a 3-LOP fix plots in a triangle, the center of the triangle is the estimated position.
    N d. It is usually based on soundings.

1090: What weather conditions would you expect to find at position A? (D049NG )

    Y a. Winds NW-W at 15 knots, partly cloudy, and slight seas
    N b. winds SW-S at 20 knots, heavy rain, and rough seas
    N c. Winds calm, light rain, and calm seas
    N d. Winds NE-E at 20 knots, heavy rain, and rough seas

1114: Mechanical lifting of air by the upslope slant of the terrain is called __________.

    N a. vertical lifting
    N b. convective lifting
    N c. advective lifting
    Y d. topographic lifting

1262: A safe water daymark has what shape?

    N a. Triangular
    N b. Diamond
    N c. Circular
    Y d. Octagonal

1321: A lighthouse can be identified by its __________.

    N a. painted color
    N b. light color and phase characteristic
    N c. type of structure
    Y d. All of the above

1354: A ship is in longitude 54°00'W on a true course of 090°. 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
    Y b. 52°30'W
    N c. 60°00'W
    N d. 67°30'W

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

1411: The nominal range of a light may be accurately defined as the maximum distance at which a light may be seen __________.

    N a. under existing visibility conditions
    N b. under perfect visibility
    Y c. with ten miles visibility
    N d. with fifteen miles visibility

1419: The MOST important feature of the material used for making the binnacle of a standard magnetic compass is that it is __________.

    Y a. nonmagnetic
    N b. weatherproof
    N c. corrosion resistant
    N d. capable of being permanently affixed to the vessel

1571: Which sextant in illustration D043NG reads 29°42.7'? (D043NG )

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

1625: A sling psychrometer is used to measure __________.

    N a. seawater temperature
    N b. engine temperature
    Y c. dry bulb and wet bulb temperatures
    N d. barometric pressure

1749: If the current and wind are in opposite directions, the sea surface represents __________.

    N a. a greatly reduced wind speed
    Y b. a higher wind speed than what really exists
    N c. a lower wind speed than what really exists
    N d. more turbulent winds

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

1944: In the horizon system of coordinates what is the equivalent to the celestial equator of the celestial equator system?

    Y a. Horizon
    N b. Prime vertical circle
    N c. Prime meridian
    N d. Principal vertical circle

1968: The Earth has the shape of a(n) __________.

    N a. sphere
    Y b. oblate spheroid
    N c. spheroid of revolution
    N d. oblate eggoid

2126: Your chart indicates that there is an isolated rock and names the rock using vertical letters. This indicates the __________.

    N a. rock is visible at low water springs only
    N b. rock is a hazard to deep draft vessels only
    Y c. rock is dry at high water
    N d. exact position of the rock is doubtful

2178: The Flinders bar and the quadrantal spheres should be tested for permanent magnetism at what interval?

    N a. They are not subject to permanent magnetism; no check is necessary.
    N b. Semiannually
    Y c. Annually
    N d. Every five years

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

2356: As observed from the Earth, the angle between lines from the Earth to the Sun and the Earth to an inferior planet is known as __________.

    Y a. elongation
    N b. conjunction
    N c. opposition
    N d. quadrature

2372: In the North Sea area, you sight a buoy showing a quick white light showing 6 flashes followed by one long flash at 15 second intervals. Which of the four topmarks illustrated in diagram D031NG would be fitted to this buoy? (D031NG )

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

2376: A large group of stars revolving around a center is known as a __________.

    N a. cluster
    N b. shower
    N c. constellation
    Y d. galaxy

2388: The reference point for determination of GMT is the passage of the mean sun over what line?

    N a. First point of Aries
    N b. Observer's meridian
    N c. 0° longitude
    Y d. 180° longitude

2416: An orange and white buoy indicating a vessel-exclusion area will be marked with what symbol?

    N a. Open-faced diamond
    Y b. Diamond with a cross
    N c. Circle
    N d. Square

2436: Aphelion is the point where the Sun __________.

    N a. and Moon and Earth form a right angle
    N b. and Moon and Earth are in line
    N c. crosses the celestial equator
    Y d. is farthest from the Earth

2518: In low latitudes, the full Moon will always rise at about __________.

    N a. sunrise
    N b. 1200 LMT
    Y c. sunset
    N d. 2400 LMT

2524: What is the equivalent of 2° 35' in time units?

    Y a. 10 min. 20 sec.
    N b. 9 min. 10 sec.
    N c. 7 min. 06 sec.
    N d. 6 min. 43 sec.

2538: The light characteristic of composite group flashing (2 + 1) is used in the Aids to Navigation System on the Western Rivers for lights on __________.

    N a. the right descending bank
    N b. the left descending bank
    Y c. preferred-channel buoys
    N d. daymarks with no lateral significance

2648: The 3-cm radar as compared to a 10-cm radar with similar specifications will __________.

    N a. give better range performance in rain, hail, etc.
    N b. display small targets in a mass of dense sea clutter at a greater range
    N c. have less sea return in choppy rough seas
    Y d. display a more maplike presentation for inshore navigation

2672: When you are steering on a pair of range lights and find the upper light is in line above the lower light, you should __________.

    Y a. continue on the present course
    N b. come left
    N c. come right
    N d. wait until the lights are no longer in a vertical line

2703: Which publication indicates the HYDROLANTS or HYDROPACS issued since the previous working day?

    N a. Broadcast Notice to Mariners
    N b. Local Notice to Mariners
    Y c. Daily Memorandum
    N d. Summary of Corrections

2705: Information about the direction and velocity of rotary tidal currents is found in the __________.

    Y a. Tidal Current Tables
    N b. Mariner's Guide
    N c. Tide Tables
    N d. Nautical Almanac

2725: A position that is obtained by using two or more intersecting lines of position taken at nearly the same time, is a(n) __________.

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

2769: If your vessel must pass through a draw during a scheduled closure period, what signal should you sound to request the opening of the draw?

    N a. One prolonged blast followed by one short blast
    N b. Three short blasts
    N c. One prolonged blast followed by three short blasts
    Y d. Five short blasts

2814: In low latitudes the range of the diurnal variation of pressure is up to __________.

    N a. 0.5 millibar
    Y b. 3.0 millibars
    N c. 6.0 millibars
    N d. 10.0 millibars

3023: You have steadied up on a range dead ahead in line with your keel. After a few minutes the range, still dead ahead, appears as shown. Which action do you take? (D047NG )

    Y a. Alter heading to the left
    N b. Alter heading to the right
    N c. Increase speed
    N d. Maintain heading, keeping the range dead ahead

3035: A major advantage of the NAVTEX system when compared to other systems is that __________.

    N a. the information can be received on an ordinary FM radio
    Y b. warnings are printed out for reading when convenient
    N c. broadcasts are at scheduled times
    N d. a low frequency band is used for long distance transmission

3039: As you enter a U.S. channel from seaward the numbers on the buoys __________.

    N a. increase with the can buoys being even numbered
    Y b. increase with the can buoys being odd numbered
    N c. decrease with the can buoys being even numbered
    N d. increase in channels going to the north or west, and decrease in channels going to the south or east

3054: In illustration D051NG, the position labeled C was plotted because __________.

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

3113: With respect to automatic identification systems (AIS), which information is required to be broadcast every 1 to 10 seconds?

    N a. Call sign
    N b. Vessel's draft
    N c. Route plan
    Y d. None of the above

3121: The short text messaging feature of the automatic identification system (AIS) allows for messages of up to___.

    N a. 64 characters
    N b. 96 characters
    Y c. 158 characters
    N d. 256 characters

3129: Which of the following statements is TRUE regarding automatic identification systems (AIS) ?

    Y a. The master may, at his/her discretion, turn off the AIS if he/she believes that it may compromise the safety or security of the vessel.
    N b. Under no circumstances shall AIS be turned off while underway as this could endanger the vessel and those around her.
    N c. AIS is always required to be operating if the vessel is in or in the vicinity of a VTS area.
    N d. AIS is always required to be operating if the vessel is within 100 nautical miles of the coastline.