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.


2: On an isomagnetic chart, the line of zero variation is the __________.


84: When using an echo sounder in deep water, it is NOT unusual to __________.


85: Your longitude is 179°59'W. The LMT at this longitude is 23h 56m of the 4th day of the month. Six minutes later your position is 179°59'E longitude. Your LMT and date is now __________.


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

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

136: Which Beaufort force indicates a wind speed of 65 knots?

    N a. Beaufort force 0
    N b. Beaufort force 6.5
    Y c. Beaufort force 12
    N d. Beaufort force 15

166: On the pole side of the high pressure belt in each hemisphere, the pressure diminishes. The winds along these gradients are diverted by the Earth's rotation toward the east and are known as the __________.

    N a. geostrophic winds
    N b. doldrums
    N c. horse latitudes
    Y d. prevailing westerlies

199: Civil twilight occurs at 0558 zone time on 30 December 1981. Your DR position at that time is LAT 15°02'N, LONG 46°02'W. Which statement concerning the planets available for morning sights is TRUE?

    Y a. At 0558, Mars can be used for an ex-meridian observation.
    N b. Venus, Jupiter, and Mars sights will yield a good three line fix.
    N c. Saturn will be near the prime vertical.
    N d. Venus will be visible low in the western sky.

310: Which sextant shown has an index error of 3'30" off the arc? (D050NG )

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

326: You are steaming west in the North Atlantic in an extratropical cyclonic storm, and the wind is dead ahead. According to the law of Buys Ballot, the center of low pressure lies to the __________.

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

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

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

504: Barometer readings in weather reports are given in terms of pressure at __________.

    Y a. sea level
    N b. Washington, D.C.
    N c. the weather station
    N d. the broadcasting station

525: In the celestial equator system of coordinates, what is comparable to latitude on the terrestrial sphere?

    N a. Altitude
    N b. Right ascension
    N c. Celestial meridians
    Y d. Declination

614: A marine chronometer should be rewound once every __________.

    N a. 12 hours
    Y b. day
    N c. 3 days
    N d. week

736: A line on a weather chart connecting places which have the same barometric pressure is called an __________.

    N a. isotherm
    N b. isallobar
    Y c. isobar
    N d. isotope

894: On a clear, warm day, you notice the approach of a tall cumulus cloud. The cloud top has hard well defined edges and rain is falling from the dark lower edge. Should this cloud pass directly overhead __________.

    Y a. it will be preceded by a sudden increase in wind speed
    N b. it will be preceded by a sudden decrease in wind speed
    N c. the wind speed will not change as it passes
    N d. the wind will back rapidly to left in a counterclockwise direction as it passes

912: The Light List Does NOT contain information on __________.

    N a. the Global Positioning System (GPS)
    Y b. aeronautical lights useful for marine navigation
    N c. radio beacon systems
    N d. radio direction finder calibration stations

930: Which statement about radio navigational warnings is TRUE?

    Y a. The topics for warnings included in HYDROLANTS, HYDROPACS, and NAVAREA warnings are the same.
    N b. NAVAREA warnings concern only coastal navigation and inland navigation in large bays or sounds such as Puget Sound.
    N c. The United States is responsible for NAVAREA warnings in the North Atlantic north of 7°N, and west of 15°W.
    N d. Long range radio navigational warnings are usually broadcast by radiotelephone, radiotelegraph, and radio-teletypewriter.

954: A thin, whitish, high cloud popularly known as "mares' tails" is __________.

    N a. altostratus
    N b. stratus
    N c. cumulus
    Y d. cirrus

962: Chart legends which indicate a conspicuous landmark are printed in __________.

    N a. underlined letters
    N b. boldfaced print
    N c. italics
    Y d. capital letters

1042: What is the approximate geographic range of Shinnecock Light, NY, if your height of eye is 24 feet (7.3 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 8.7 nm
    N b. 9.9 nm
    N c. 14.4 nm
    Y d. 15.9 nm

1102: What is the approximate geographic range of Race Rock Light, NY, if your height of eye is 27 feet (8.2 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 9.9 nm
    N b. 14.3 nm
    Y c. 15.7 nm
    N d. 17.4 nm

1105: The Light List shows that a navigational light has a nominal range of 22 miles and a height above water of 48 feet (14.6 meters). Your height of eye is 35 feet (10.7 meters) and the visibility is 20.0 miles. At what approximate range will you first sight the light?

    N a. 10.5 nm
    N b. 13.2 nm
    Y c. 14.7 nm
    N d. 32.0 nm

1154: The speed at which an ocean wave system advances is called __________.

    N a. wave length
    N b. ripple length
    Y c. group velocity
    N d. wave velocity

1185: An orange and white buoy with a rectangle on it displays __________.

    N a. directions
    N b. distances
    N c. locations
    Y d. All of the above

1274: The Illustration shows the symbols used on radio facsimile weather charts. Which of these symbols indicates a sandstorm? (D042NG )

    N a. H
    Y b. O
    N c. P
    N d. K

1356: The first indications a mariner will have of the approach of a warm front will be __________.

    N a. large cumulonimbus (thunderclouds) building up
    Y b. high cirrus clouds gradually changing to cirrostratus and then to altostratus
    N c. fog caused by the warm air passing over the cooler water
    N d. low dark clouds accompanied by intermittent rain

1446: When compared to air temperature, which factor is most useful in predicting fog?

    N a. Vapor pressure
    Y b. Dew point
    N c. Barometric pressure
    N d. Absolute humidity

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

1536: What will NOT induce errors into a Doppler sonar log?

    Y a. Increased draft
    N b. Pitch
    N c. Roll
    N d. Change in trim

1610: When the navigational channel passes under a fixed bridge, the edges of the channel are marked on the bridge with what lights?

    Y a. Red lights
    N b. Three white lights in a vertical line
    N c. Red lights on the LDB and green lights on the RDB
    N d. Yellow lights

1660: Which of the following is TRUE of advection fog?

    N a. It commonly occurs on coastal waters during cold seasons.
    N b. It moves in a bank or dense cloud.
    N c. It is caused by warmer air moving to a cooler location.
    Y d. All of the above

1692: The force resulting from the earth's rotation that causes winds to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere is called __________.

    N a. pressure gradient
    Y b. Coriolis effect
    N c. aurora borealis
    N d. ballistic deflection

1789: The Illustration represents a fixed C of E lock and dam. What navigational light(s) is(are) exhibited at the position indicated by the letter F in the illustration? (D036NG )

    Y a. One red light
    N b. Two green lights
    N c. Three green lights
    N d. No light(s)

1836: At evening stars, the first stars that should be observed are those with an azimuth in what quadrant?

    N a. Southern
    N b. Western
    N c. Northern
    Y d. Eastern

2061: Fog is likely to occur when there is little difference between the dew point and the __________.

    N a. relative humidity
    Y b. air temperature
    N c. barometric pressure
    N d. absolute humidity

2067: The Light List indicates that a light has a nominal range of 10 miles and is 11 feet high. If the visibility is 5 miles and your height of eye is 20 feet, at what approximate distance will you sight the light?

    Y a. 6.3 miles
    N b. 7.4 miles
    N c. 8.4 miles
    N d. 9.0 miles

2084: You are approaching Gallipolis Lock and Dam. The traffic signal light is flashing red. You should __________.

    Y a. hold your position and not attempt to enter the lock
    N b. approach the lock slowly under full control
    N c. proceed at normal speed to enter the lock
    N d. None of the above

2166: 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
    Y b. Three red lights
    N c. Two red lights
    N d. One red light

2299: What condition exists at apogee?

    N a. The Earth is closest to the Sun.
    N b. The Moon is farthest from the Sun.
    Y c. The Earth is farthest from the Moon.
    N d. The Moon is between the Earth and the Sun.

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

2428: If your vessel were proceeding up river (ascending), the port side of the channel would be marked according to the U. S. Aids to Navigation System on the Western Rivers by __________.

    Y a. green can buoys
    N b. red can buoys
    N c. green nun buoys
    N d. red nun buoys

2481: The letter D as shown represents the __________. (D006NG )

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

2482: When a vessel changes course from one cardinal heading to another cardinal heading while adjusting the compass, which action should be taken?

    N a. The course change should be made rapidly to prevent transient induced magnetism while passing the intercardinal headings.
    Y b. After the new heading is reached, the vessel should steam on that course for at least two minutes before the adjustment.
    N c. During the course change, you should gently tap the compass to remove any error caused by friction on the pivot bearing.
    N d. After steadying on the new heading, the compass card should be slewed by a magnet and allowed to oscillate freely to remove any gaussin error.

2506: Which is TRUE on the Western Rivers when a vessel downbound with a following current is meeting an upbound vessel?

    Y a. She has the right of way only if she is a power-driven vessel.
    N b. She has the right of way only if she has a tow.
    N c. She does not have the right of way, since the other vessel is not crossing the river.
    N d. She must wait for a whistle signal from the upbound vessel.

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.

2578: You must draw a plotting sheet covering latitudes 49°N to 53°N and longitudes 179°E to 178°W. If the distance between latitude 49°N to 53°N is 16 inches, what is the distance between the meridians of 1° of longitude?

    N a. 2.12 inches
    N b. 2.33 inches
    Y c. 2.56 inches
    N d. 2.81 inches

2590: A plane perpendicular to the polar axis will never form what line on the Earth's surface?

    N a. Great circle
    N b. Equator
    N c. Small circle
    Y d. Meridian

2618: You must draw a plotting sheet covering latitudes 38°N to 43°N and longitudes 179°E to 178°W. If the distance between each degree of longitude is 5 inches, what is the distance between latitude 38°N and latitude 43°N?

    N a. 29.0 inches
    N b. 29.6 inches
    N c. 32.1 inches
    Y d. 32.8 inches

2620: The navigator is concerned with three systems of coordinates. Which system is not of major concern?

    N a. Terrestrial
    Y b. Ecliptic
    N c. Celestial horizon
    N d. Celestial equator

2729: While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 5.5 seconds after the signal was sounded. What is the distance to the shore?

    N a. 3825 ft (1166 meters)
    N b. 3450 ft (1052 meters)
    Y c. 3072 ft (936 meters)
    N d. 2475 ft (754 meters)

2760: You are pushing a tow ahead, at high speed, near the right hand bank of a canal. The forces affecting your towboat and tow will tend to __________.

    N a. push both the head of the tow and the stern of the towboat away from the right hand bank
    Y b. push the head of the tow away from, and pull the stern of the towboat into, the right hand bank
    N c. pull both the head of the tow and the stern of the towboat into the right hand bank
    N d. pull the head of the tow into, and push the stern of the towboat away from, the right hand bank

2830: The proper way to approach a downstream lock where there is an outdraft is to be __________.

    N a. wide out from the land wall, keeping the stern in at all times
    N b. wide out from the land wall, keeping the stern out at all times
    Y c. close in to the land wall, keeping the stern in at all times
    N d. close in to the land wall, keeping the stern out at all times

2852: A daymark warning of a danger will have the shape indicated by which letter? (D045NG )

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

2928: You are in a buoyed channel at night and pass a lighted buoy with an irregular characteristic. You should report this to the __________.

    Y a. Coast Guard
    N b. harbor master
    N c. Corps of Engineers
    N d. National Ocean Service

2982: You take a bearing of 142° and 259° of two objects. What bearing of a third object will give the best fix? -

    Y a. 019°
    N b. 084°
    N c. 166°
    N d. 281°

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

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