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.


20: You are underway on course 050°T and your maximum speed is 12 knots. The eye of a hurricane bears 120°T, 110 miles from your position. The hurricane is moving towards 285°T at 25 knots. If you maneuver at 12 knots to avoid the hurricane, what could be the maximum CPA?


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


172: A chart with a scale of 1:45,000 is a __________.


230: If the LORAN-C ground wave does NOT extend out as far as the skywave skip distance, there will be a skip zone in which __________.

    Y a. no LORAN-C signal is received
    N b. only ground waves are received
    N c. only skywaves are received
    N d. both ground waves and skywaves are received

298: A great circle crosses the equator at 173°E. It will also cross the equator at what other longitude?

    Y a. 7°W
    N b. 73°E
    N c. 73°W
    N d. 173°W

367: What will be the time after 0800 EST (ZD +5) that the height of the tide at South Freeport, ME, will be 6.0 feet (1.8 meters) on 7 November 1983?

    N a. 0936
    N b. 0942
    Y c. 0951
    N d. 1001

424: For an accurate barometer check, you would __________.

    N a. check it with a barometer on another vessel
    N b. take readings from several barometers and average them
    N c. check it with the barometer at the ship chandlery
    Y d. check it against radio or National Weather Service reports of the immediate vicinity

431: When a buoy marks a channel bifurcation, the preferred channel is NOT indicated by __________.

    N a. the shape of an unlighted buoy
    N b. the light color of a lighted buoy
    N c. the color of the topmost band
    Y d. whether the number is odd or even

474: Which indication on the barometer is most meaningful in forecasting weather?

    N a. The words "Fair -- Change -- Rain"
    Y b. The direction and rate of change of barometric pressure
    N c. The actual barometric pressure
    N d. The relative humidity

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.

533: You are using a radar in which your own ship is shown at the center, and the heading flash always points to 0°. If bearings are measured in relation to the flash, what type of bearings are produced?

    Y a. Relative
    N b. True
    N c. Compass
    N d. Magnetic

568: The chart of a beach area shows a very steep slope to the underwater beach bottom. Which type of breakers can be expected when trying to land a boat on this beach?

    Y a. Surging
    N b. Converging
    N c. Spilling
    N d. Plunging

580: On 21 January 1981, you observe a back sight of the Sun's lower limb. The sextant altitude (hs) is 121°31.5'. The index error is 2.5' on the arc. The height of eye is 31 feet (9.3 meters). What is the observed altitude (Ho)?

    N a. 31°06.2'
    Y b. 58°53.1'
    N c. 58°12.2'
    N d. 58°03.2'

585: What great circle is always needed to form the astronomical triangle?

    N a. Celestial Equator
    N b. Prime Meridian
    Y c. Celestial Meridian
    N d. Prime Vertical Circle

612: Which statement is TRUE concerning a Mercator projection?

    N a. Degrees of longitude decrease in length as latitude increases.
    Y b. The length of the meridians is increased to provide for equal expansion in all directions.
    N c. The mileage between the meridians is increased as the latitude increases.
    N d. All of the above

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°

710: What is the FIRST sign of the existence of a well developed tropical cyclone?

    N a. Gale force winds from the north
    Y b. An unusually long ocean swell
    N c. Steep, short-period waves and light wind
    N d. Thunderstorms and higher than usual humidity

719: You are on course 209°T. In order to check the longitude of your vessel, you should observe a celestial body on which bearing?

    N a. 209°
    Y b. 270°
    N c. 299°
    N d. 000°

774: Variation is not constant; it is different with every change in __________.

    N a. speed
    N b. vessel heading
    Y c. geographical location
    N d. cargo

886: The circulation around a low pressure center in the Northern Hemisphere is __________.

    Y a. counterclockwise
    N b. variable
    N c. clockwise
    N d. anticyclonic

892: When a buoy is in position only during a certain period of the year, where may the dates when the buoy is in position be found?

    Y a. Light List
    N b. Notice to Mariners
    N c. On the chart
    N d. Coast Pilot

914: If the sky was clear, with the exception of a few cumulus clouds, it would indicate __________.

    N a. rain
    N b. hurricane weather
    Y c. fair weather
    N d. fog setting in

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

1120: You are on course 042°T. To check the course of your vessel you should observe a celestial body on which bearing?

    N a. 090°
    Y b. 132°
    N c. 180°
    N d. 222°

1181: An occulting light is one in which __________.

    N a. the period of darkness exceeds the period of light
    N b. there is only a partial eclipse of the light
    N c. the periods of light and darkness are equal
    Y d. the period of light exceeds the period of darkness

1181: An occulting light is one in which __________.

    N a. the period of darkness exceeds the period of light
    N b. there is only a partial eclipse of the light
    N c. the periods of light and darkness are equal
    Y d. the period of light exceeds the period of darkness

1224: NGA (NIMA) charts are adopting the metric system. In order to change a charted depth in meters to feet you may use the conversion table found __________.

    N a. in the Light List
    N b. in Bowditch Vol. II
    N c. on the chart
    Y d. All of the above

1275: How is variation indicated on a small-scale nautical chart?

    N a. Magnetic compass table
    N b. Magnetic meridians
    Y c. Isogonic lines
    N d. Variation is not indicated on small-scale nautical charts.

1312: Which factor(s) is/are used to develop the charted information of a lighthouse?

    Y a. Height and intensity of the light
    N b. Height of the light and the observer
    N c. Height of the observer and the intensity of the light
    N d. Height of the light only

1349: The symbols shown are used on radio facsimile weather charts. Which of these symbols indicates a severe squall line? (D042NG )

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

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

1400: Which type of cloud is among the most dependable for giving an indication of an approaching weather system?

    N a. Cumulus
    Y b. Altostratus
    N c. Cumulostratus
    N d. Nimbus

1410: A white buoy marked with an orange rectangle indicates __________.

    N a. a fish net area
    Y b. general information
    N c. an anchorage
    N d. mid-channel

1421: What is the approximate geographic visibility of an object with a height above the water of 70 feet, for an observer with a height of eye of 65 feet?

    N a. 16.8 nm
    Y b. 19.0 nm
    N c. 20.6 nm
    N d. 22.4 nm

1514: The compass error of a magnetic compass that has no deviation is __________.

    N a. zero
    Y b. equal to variation
    N c. eliminated by adjusting the compass
    N d. constant at any geographical location

1582: Sextant C in illustration D043NG reads __________. (D043NG )

    N a. 30°45.9'
    N b. 29°56.0'
    N c. 29°52.0'
    Y d. 29°47.5'

1611: What indicates a dual purpose buoy?

    N a. Red buoy with a horizontal yellow band
    N b. Red and white vertically-striped buoy with a vertical yellow stripe
    N c. Red and white vertically-striped buoy with a red spherical topmark
    Y d. Green buoy with a yellow square

1623: Which of the following statements is FALSE?

    N a. An anemometer measures wind speed.
    N b. A barometer measures atmospheric pressure.
    N c. A thermometer measures temperature.
    Y d. A psychrometer measures wind pressure.

1637: Which of the following is NOT a form of precipitation?

    N a. rain
    Y b. frost
    N c. sleet
    N d. snow

1653: In a weather report, the term "visibility" expresses __________.

    N a. how far you can see with the "naked eye"
    N b. how far you can see with a telescope or binoculars
    N c. how well you can identify an object at night
    Y d. the distance in miles at which prominent objects are identifiable

1659: The type of fog that occurs on clear nights with very light breezes and forms when the earth cools rapidly by radiation is known as __________.

    Y a. radiation fog
    N b. frontal fog
    N c. convection fog
    N d. advection fog

1678: Which information is NOT provided in broadcasts by the National Institute of Standards and Technology?

    N a. Storm Warnings
    N b. Time Announcements
    N c. GPS Information
    Y d. NAVAREA Warnings

1680: A weather front exists when __________.

    N a. air masses of the same temperature meet
    Y b. air masses of different temperatures meet
    N c. many clouds create a differential in air density
    N d. two lows are separated by a ridge of higher pressure

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

1873: Lighted information markers show __________.

    N a. green lights
    N b. red lights
    N c. yellow lights
    Y d. white lights

1952: The Moon is subject to four types of libration. Which of the following is NOT one of these types of libration?

    N a. Libration in longitude
    Y b. Geocentric libration
    N c. Diurnal libration
    N d. Physical libration

2016: Which statement about the Flinders bar of the magnetic compass is CORRECT?

    Y a. It compensates for the error caused by the vertical component of the Earth's magnetic field.
    N b. It compensates for error caused by the heeling of a vessel.
    N c. It compensates for quadrantal deviation.
    N d. It is only needed in equatorial waters.

2093: Information about major breakdowns, repairs, or other emergency operations with regard to weirs and (or) wicket dams, on the western rivers, may be obtained from the __________.

    N a. Light List Vol. V
    N b. List of Lights
    Y c. Broadcast Notice to Mariners
    N d. Sailing Directions

2101: Information about major breakdowns, repairs, or other emergency operations with regard to weirs and (or) wicket dams, on the western rivers, may be obtained by consulting the __________.

    Y a. Broadcast Notice to Mariners
    N b. Light List Vol. V
    N c. U.S. Coast Pilot
    N d. All of the above

2348: Under the IALA cardinal system, a mark with a quick light showing 9 flashes every 15 seconds indicates that the safest water is on the __________.

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

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

2389: The autumnal equinox is the point where the Sun is at __________.

    N a. maximum declination north
    N b. maximum declination south
    N c. 0° declination going to northerly declinations
    Y d. 0° declination going to southerly declinations

2442: You have completed the magnetic compass adjustments on magnetic east and magnetic south. The vessel is now steady on magnetic north but the compass reads 004°. You should now adjust the compass until it reads __________.

    N a. 356°
    N b. 358°
    N c. 000°
    Y d. 002°

2452: The permanent magnetism of a vessel may change in strength due to __________.

    N a. the nature of the cargo being carried
    N b. changes in heading
    Y c. major structural repair
    N d. All of the above

2598: A vessel is proceeding downstream in a narrow channel on the Western Rivers when another vessel is sighted moving upstream. Which vessel has the right of way?

    N a. The vessel moving upstream against the current
    Y b. The vessel moving downstream with a following current
    N c. The vessel located more towards the channel centerline
    N d. The vessel with the least amount of maneuverability

2768: Which type of daymark is used to mark the starboard side of the channel when entering from sea?

    N a. Red and white octagon
    N b. Black and white diamond
    Y c. Red triangle
    N d. Green square

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°

2798: A can buoy is indicated by which letter in illustration D044NG?

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

2882: While upbound through Memphis, the weather report on TV news indicates that a warm front is stationary over the Kentucky - Missouri - Tennessee areas. What weather conditions should you expect?

    N a. Strong, gusting winds from the NW with thundershowers
    N b. Light winds from the northeast with clear skies
    N c. A "blue norther"
    Y d. Southerly winds with steady rain; fog or overcast

3074: ECDIS must give an alarm for which of the following cases?

    N a. When the speed of a dangerous target exceeds a set limit
    Y b. When the specified limit for deviation from the planned route is exceeded
    N c. If the ship's ETA has changed beyond the set limit
    N d. None of the above