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.


86: A weather forecast states that the wind will commence backing. In the Northern Hemisphere, this would indicate that it will __________.


139: What is the geographic longitude of a body whose GHA is 215°15'?


147: Which statement is TRUE concerning equatorial tides?


275: Which statement concerning illustration is correct? (Soundings and heights are in meters) (D010NG )

    Y a. The sunken wreck southwest of Beito Island shows the hull or superstructure above the sounding datum.
    N b. There is a 12-meter deep hole inside the 5-meter curve just west of Beito Island.
    N c. The position of the lightship is indicated by the center of the star on the symbol's mast.
    N d. Maury Lightship swings about her anchor on a circle with a 21-meter diameter.

282: The symbol which appears beside a light on a chart reads "Gp Fl R (2) 10 sec 160 ft 19M". Which characteristic describes the light?

    N a. It is visible 10 miles.
    N b. Its distinguishing number is "19M".
    N c. It has a radar reflector.
    Y d. None of the above

316: According to Buys Ballot's law, when an observer in the Northern Hemisphere experiences a northwest wind, the center of low pressure is located to the __________.

    Y a. northeast
    N b. west-southwest
    N c. northwest
    N d. south-southeast

319: The Illustration shows the symbols used by radio facsimile weather charts. The symbol indicated at letter "F" represents a __________. (D042NG )

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

327: When daylight savings time is kept the times of tide and current calculations must be adjusted. One way of doing this is to __________.

    N a. subtract one hour from the times listed under the reference stations
    Y b. add one hour to the times listed under the reference stations
    N c. apply no correction, as the times in the reference stations are adjusted for daylight savings time
    N d. add 15° to the standard meridian when calculating the time difference

359: You are enroute to assist vessel A. Vessel A is underway at 4.5 knots on course 233°T, and bears 264°T, 68 miles from you. What is the time to intercept if you make 13 Knots?

    N a. 6h 31m
    N b. 6h 47m
    N c. 7h 03m
    Y d. 7h 34m

376: According to Buys Ballot's law, when an observer in the Northern Hemisphere experiences a northeast wind the center of low pressure is located to the __________.

    N a. northeast
    N b. west-southwest
    N c. northwest
    Y d. south-southeast

376: According to Buys Ballot's law, when an observer in the Northern Hemisphere experiences a northeast wind the center of low pressure is located to the __________.

    N a. northeast
    N b. west-southwest
    N c. northwest
    Y d. south-southeast

384: Which is a nonadjustable error of the sextant?

    N a. Error of perpendicularity
    N b. Side error
    N c. Error of collimation
    Y d. Centering error

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

465: When applying a dip correction to the sighted sextant angle (hs), you always subtract the dip because you are correcting __________.

    N a. hs to the visible horizon
    Y b. hs to the sensible horizon
    N c. hs to the celestial horizon
    N d. Ho to the celestial horizon

467: At what time after 1400 EST (ZD +5), on 4 January 1983, will the height of the tide at Port Wentworth, GA, be 3.0 feet?

    N a. 1612
    N b. 1630
    Y c. 1653
    N d. 1718

493: The picture shown represents the geographic location of a vessel and the radar presentation at the same time. Which statement is TRUE? (D011NG )

    N a. Ship No. 1 is not detected due to the shadow effect of the headland.
    N b. The small island is not detected due to the effect of beam width.
    Y c. A tangent bearing of the headland to the south-southeast should be corrected by adding one-half of the beam width.
    N d. Ship No. 2 is not detected due to the reflective mass of the background mountain overpowering the ship's reflective signals.

570: Chart legends printed in capital letters show that the associated landmark is __________.

    N a. inconspicuous
    Y b. conspicuous
    N c. a government facility or station
    N d. a radio transmitter

608: In which voyage, between two points, is the rhumb line distance NOT approximately the same as the great circle distance?

    N a. The two points are in low latitudes in the same hemisphere.
    Y b. The two points are in high latitudes in the same hemisphere.
    N c. The two points are near the equator, but in different hemispheres.
    N d. One point is near the equator, one point is in a high latitude, and both are near the 180th meridian.

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

691: Of the four light characteristics shown which one does NOT represent a safe water mark of the IALA Buoyage System? (D019NG )

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

706: A steep barometric gradient indicates __________.

    N a. calms
    N b. light winds
    Y c. strong winds
    N d. precipitation

726: Atmospheric pressure at sea level is equal to __________.

    N a. 14.7 pounds per square inch
    N b. 29.92 inches of mercury
    N c. 1013.25 millibars
    Y d. All of the above

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

    N a. a collision with another vessel
    N b. being moored on a constant heading for a long period of time
    N c. being struck by lightning
    Y d. All of the above

856: The flow of air around an anticyclone in the Southern Hemisphere is __________.

    N a. clockwise and outward
    Y b. counterclockwise and outward
    N c. clockwise and inward
    N d. counterclockwise and inward

984: The bases of middle clouds are located at altitudes of between __________.

    N a. 3,000 to 6,500 feet (914 to 1981 meters)
    Y b. 6,500 to 20,000 feet (1981 to 6096 meters)
    N c. 10,000 to 35,000 feet (3048 to 10,668 meters)
    N d. 20,000 to 60,000 feet (6096 to 18,288 meters)

1141: What is characteristic of an isophase light?

    N a. 4 sec. flash, 2 sec. eclipse, 3 sec. flash, 2 sec. eclipse
    N b. 2 sec. flash, 5 sec. eclipse
    Y c. 1 sec. flash, 1 sec. eclipse
    N d. 6 sec. flash, 3 sec. eclipse

1237: What will be the velocity of the tidal current at Port Royal, VA, at 1505 DST (ZD +4) on 4 June 1983?

    N a. 0.0 knot
    N b. 0.1 knot
    Y c. 0.4 knot
    N d. 0.7 knot

1242: Daymarks marking the starboard side of the channel when going towards the sea are __________.

    Y a. green squares
    N b. green triangles
    N c. red squares
    N d. red triangles

1316: When a warm air mass overtakes a cold air mass, the contact surface is called a __________.

    N a. line squall
    N b. water spout
    N c. cold front
    Y d. warm front

1362: Which type of cloud is indicated by the number 7 in illustration D039NG? (D039NG )

    N a. Cirrostratus
    N b. Altocumulus
    Y c. Cumulus
    N d. Cumulonimbus

1383: The spin axis of a gyroscope tends to remain fixed in space in the direction in which it is started. How does this gyroscope become north seeking so that it can be used as a compass?

    Y a. By mechanically or electrically applying forces to precess the gyroscope
    N b. By starting the compass with the spin axis in a north/south position
    N c. By taking advantage of the property of gyroscopic inertia
    N d. The rotation of the Earth (Earth rate) automatically aligns the gyroscope with north, except for speed errors

1385: What is the length of the lunar day?

    Y a. 24h 50m 00s
    N b. 24h 00m 00s
    N c. 23h 56m 04s
    N d. 23h 03m 56s

1408: An occluded front is caused by a(n) __________.

    N a. low pressure area
    N b. high pressure area
    N c. area of calm air
    Y d. cold front overtaking a warm front

1467: Determine the time after 0730 EST (ZD +5) when the velocity of the current will be 2.1 knots on 26 March 1983, at Fort Pulaski, GA.

    N a. 0802
    N b. 0812
    N c. 0821
    Y d. 0840

1482: Which statement concerning current is TRUE?

    N a. Current can be determined by measuring the direction and distance between simultaneous EP and DR positions.
    Y b. The drift of the current should be averaged out on a one hour basis.
    N c. After the current is determined, it should not be used for further plotting because it is an unknown variable.
    N d. The distance between a simultaneous DR position and fix is equal to the drift of the current.

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

1539: You are steaming in the open ocean of the North Pacific between the Aleutian Chain and Hawaii. A warning broadcast indicates that an earthquake has occurred in the Aleutians and has generated a tsunami that is predicted to hit Hawaii. What action is necessary for the ship's safety?

    N a. Calculate the tsunami's ETA at your position and turn to a course that will head into the Tsunami.
    N b. Securely stow all loose gear, check deck lashings, and prepare for extreme rolls.
    Y c. No special action as tsunamis are inconspicuous in the open ocean
    N d. Prepare for sudden, high-velocity wind gusts from rapidly changing directions.

1566: The illustration shows the symbols used on radio facsimile weather charts. Which of these symbols indicates thunderstorms? (D042NG )

    Y a. I
    N b. K
    N c. L
    N d. M

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

1727: What enables you to estimate the bearing of a storm's center?

    Y a. Buys Ballot's Law
    N b. An educated guess
    N c. Pascal's Law
    N d. The left-hand rule

1728: If a hurricane several hundred miles away is moving in your general direction your barometer would __________.

    N a. start to rise rapidly
    Y b. start to fall gradually
    N c. rise slowly, begin "pumping" and then start a slow, steady fall
    N d. remain steady

1757: Where would you obtain data on currents for areas of the world not covered by the U.S. National Ocean Service?

    N a. In the Coast Pilot
    N b. In the Nautical Almanac
    N c. In the List of Lights
    Y d. In the Sailing Directions

1762: In high latitudes, celestial observations can be made over a horizon covered with pack ice by bringing the sun tangent to the ice and __________.

    N a. adding 30° of arc to the sight
    Y b. using a dip correction based on the height of eye above the ice
    N c. doubling the semidiameter correction
    N d. using a dip correction from table 22 in Bowditch Vol. II

1767: Which statement describes the prevailing wind direction in mid-winter in the Gulf Coast area?

    Y a. 30% to 40% of mid-winter winds are from a northern quadrant.
    N b. 40% to 50% of mid-winter winds are from a southern quadrant.
    N c. the winds are variable in speed, but strongest in March.
    N d. None of the above

1832: Which magnetic compass corrector(s) can be set while the vessel is on a heading of magnetic northeast or magnetic southeast?

    N a. Flinders bar
    N b. Heeling magnets
    N c. Fore-and-aft magnets
    Y d. Quadrantal spheres

1872: To find a magnetic compass course from a true course you must apply __________.

    N a. deviation
    N b. variation
    Y c. deviation and variation
    N d. magnetic anomalies (local disturbances)

1882: The GP of a body for a high altitude sight is determined from the Greenwich hour angle and the __________.

    N a. circle of equal altitude
    N b. zenith distance
    N c. azimuth angle
    Y d. declination

2018: Which magnetic compass corrector(s) can be set while the vessel is on a heading of magnetic east or magnetic west?

    N a. Quadrantal spheres
    N b. Heeling magnet
    Y c. Flinders bar
    N d. Athwartships magnets

2052: Under the chart numbering system used by NGA (NIMA), the first digit of a multi-digit number indicates __________.

    Y a. the general geographic area
    N b. the general scale of the chart
    N c. whether it is a major or minor chart
    N d. the projection used to construct the chart

2128: 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?

    Y a. Three red lights
    N b. Two red lights
    N c. One red lights
    N d. No lights

2296: A variable star is one that __________.

    Y a. exhibits a change in magnitude
    N b. has a changing declination
    N c. is increasing in SHA
    N d. is also known as a red giant

2320: The type of current which will have the greatest effect on the course made good for your vessel is __________.

    N a. one flowing in the same direction as your course steered
    N b. one flowing in the opposite direction as your course steered
    Y c. one that flows at nearly right angles to your course steered
    N d. a rotary current in which the direction of current flow constantly changes

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

2586: A chart has extensive corrections to be made to it. When these are made and the chart is again printed, the chart issue is a __________.

    N a. first edition
    Y b. new edition
    N c. revised edition
    N d. reprint

2612: The dividing meridian between zone descriptions -7 and -8 is __________.

    Y a. 112°30'E
    N b. 118°30'E
    N c. 120°00'E
    N d. 116°30'W

2632: A section of the river that is narrower than usual and is often navigable from bank to bank is a __________.

    Y a. chute
    N b. stabilized channel
    N c. slough
    N d. navigable pass

2836: The correction tables in the front of the Nautical Almanac for use with sun sights do NOT include the effects of __________.

    N a. mean refraction
    N b. parallax
    N c. semidiameter
    Y d. irradiation

2877: Class I and II private aids to navigation in or along navigable waters of the United States are listed in the __________.

    N a. Sailing Directions
    Y b. Light List
    N c. List of Private Aids
    N d. Aids to Navigation Manual

2981: The maritime radio system consisting of a series of coast stations transmitting coastal warnings is called __________.

    Y a. NAVTEX
    N b. HYDROLANT/HYDROPAC
    N c. NAVAREA
    N d. SAFESEA

3084: An ECDIS is required to display which information?

    Y a. Soundings
    N b. Waypoints
    N c. Meteorological data
    N d. Radar targets