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.


42: The datum used for soundings on charts of the East Coast of the United States is __________.


45: The navigator aboard a ship at approximately 165°E longitude observes the Sun at ZT 14-25-04 on 21 September. What is the GMT and Greenwich date of the observation?


78: A single line of position combined with a dead-reckoning position results in a(n) __________.


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

    Y a. receive a strong return at about 200 fathoms (366 meters) during the day, and one nearer the surface at night
    N b. receive a first return near the surface during the day, and a strong return at about 200 fathoms (366 meters) at night
    N c. receive false echoes at a constant depth day and night
    N d. have to recalibrate every couple of days due to inaccurate readings

98: A position that is obtained by applying estimated current and wind to your vessel's course and speed is a(n) __________.

    N a. dead reckoning position
    Y b. estimated position
    N c. fix
    N d. None of the above

182: The scale on a chart is given as 1:5,000,000. This means that __________.

    N a. 1 inch is equal to 5,000 inches on the Earth's surface
    N b. 1 nautical mile on the chart is equal to 5,000 inches on the Earth's surface
    Y c. 1 inch is equal to 5,000,000 inches on the Earth's surface
    N d. 1 nautical mile on the chart is equal to 5,000,000 inches on the Earth's surface

193: In using Loran-C, skywave reception gives greater range but is __________.

    N a. only accurate during daylight hours
    Y b. much less accurate
    N c. only accurate at twilight
    N d. more accurate than using ground waves

203: In any Loran-C chain, there are three or more stations transmitting pulses which radiate in all directions. One of the stations is the master station, and the others in the chain are the __________.

    N a. radio stations
    Y b. secondary stations
    N c. monitor stations
    N d. pulse stations

219: The predicted time that the flood begins at the entrance to Delaware Bay is 1526. You are anchored off Chestnut St. in Philadelphia. If you get underway bound for sea at 1300 and turn for 13 knots, at what point will you lose the flood current?

    N a. Mile 52
    N b. New Castle
    N c. Marcus Hook
    Y d. Billingsport

255: On March 17, at 0500 zone time, you cross the 180th meridian steaming eastward to west longitude. What is your local time?

    N a. You are in -12 time zone.
    N b. It is 1700, March 18.
    Y c. It is 0500, March 16.
    N d. It is 0500, March 18.

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

304: In order to remove index error from a sextant, you should adjust the __________.

    N a. index mirror to make it parallel to the horizon glass with the index set at zero
    Y b. horizon glass to make it parallel to the index mirror with the index set at zero
    N c. horizon glass to make it parallel to the sextant frame
    N d. telescope to make it perpendicular to the sextant frame

441: A yellow buoy may exhibit a(n) __________.

    N a. fixed red light
    Y b. flashing light
    N c. white light
    N d. occulting light

447: On 27 April 1983, at 1105 DST (ZD +4), what will be the predicted height of tide at Falkner Island, CT?

    Y a. 5.3 feet (1.6 m)
    N b. 5.6 feet (1.7 m)
    N c. 6.2 feet (1.9 m)
    N d. 6.8 feet (2.7 m)

491: A special purpose buoy shall be __________.

    N a. lighted with a white light
    N b. striped black and red
    N c. lighted with a red light
    Y d. yellow

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.

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

680: The apparent wind's speed can be zero, but only when two conditions are present. One condition is that the true __________.

    N a. wind must be on the beam
    N b. wind's speed must be zero
    N c. wind must be from dead ahead
    Y d. wind's speed equals the ship's speed

830: The highest frequency of tropical cyclones in the North Atlantic Ocean occurs during __________.

    N a. January, February and March
    N b. April, May and June
    Y c. August, September and October
    N d. July, November and December

849: The Light List shows that a navigational light has a nominal range of 12 miles and a height above water of 25 feet (7.6 meters). Your height of eye is 30 feet (9.1 meters) and the visibility is 0.5 mile. At what approximate range will you first sight the light?

    N a. 0.5 mile
    Y b. 1.4 miles
    N c. 5.2 miles
    N d. 12.0 miles

874: Altocumulus clouds are defined as __________.

    N a. high clouds
    Y b. middle clouds
    N c. low clouds
    N d. vertical development clouds

955: The line of position determined from a sight with an observed altitude (Ho) of 88°45.0' should be __________.

    N a. reduced to the meridian and plotted as a latitude line
    N b. calculated as a longitude line
    N c. plotted by using an intercept from an assumed position
    Y d. plotted as an arc around the GP of the body

991: You are underway in the North Sea on course 328°T when you sight a buoy broad on your port bow. You are in the best navigable water if the buoy __________.

    N a. has a topmark of two cones with points down
    N b. is a western quadrant buoy
    N c. is painted yellow on the top half and black on the bottom
    Y d. exhibits a light with the characteristic of VQ(3)5s

1020: The Light List shows that a navigational light has a nominal range of 6 miles and a height above water of 18 feet (5.5 meters). Your height of eye is 40 feet (12.2 meters) and the visibility is 27.0 miles. At which approximate range will you first sight the light?

    N a. 5.6 miles
    N b. 6.4 miles
    Y c. 9.8 miles
    N d. 12.1 miles

1056: The steepness of a cold front depends on __________.

    N a. the direction of wind around the front
    Y b. its velocity
    N c. the temperature of the air behind the front
    N d. the precipitation generated by the front

1073: Chart legends printed in capital letters show that the associated landmark is __________.

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

1081: On a voyage along the coast of France, you sight a buoy with the top marks as shown. You are required to steer __________. (D026NG )

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

1093: The Flinders bar on a magnetic compass compensates for the __________.

    Y a. induced magnetism in vertical soft iron
    N b. induced magnetism in horizontal soft iron
    N c. permanent magnetism in ship's steel
    N d. vessel's inclination from the vertical

1099: You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133°T, and bears 343°T at 92 miles from you. What is the course to steer at 9 knots to intercept vessel A?

    N a. 356°
    Y b. 003°
    N c. 022°
    N d. 038°

1103: The vertical component of the Earth's magnetic field causes induced magnetism in vertical soft iron. This changes with latitude. What corrects for this coefficient of the deviation?

    Y a. The Flinders bar
    N b. The heeling magnet
    N c. Quadrantal soft iron spheres
    N d. Bar magnets in the binnacle

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

1248: On 6 July 1983, at 1520 DST (ZD +4) what will be the predicted height of tide at Newburgh, NY?

    N a. 2.1 feet
    N b. 1.7 feet
    N c. 1.2 feet
    Y d. 0.6 foot

1285: You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033°T, and bears 248°T at 64 miles from you. What is the time to intercept if you make 13 knots?

    N a. 4h 55m
    N b. 4h 36m
    N c. 3h 59m
    Y d. 3h 44m

1306: What type of clouds are associated with a cold front?

    N a. Altostratus and fracto-cumulus
    N b. Altostratus and cirrus
    N c. Cirrus and cirrostratus
    Y d. Cumulus and cumulonimbus

1347: What will be the velocity of the tidal current south of Doubling Point, ME, at 1357 EST (ZD +5) on 3 April 1983?

    N a. 0.9 knot
    N b. 1.3 knots
    Y c. 2.0 knots
    N d. 2.6 knots

1454: Atmospheric pressure may be measured with a(n) __________.

    N a. barograph
    N b. aneroid barometer
    N c. mercurial barometer
    Y d. All of the above

1504: The time meridian used when computing the height of tide for Pensacola Bay, FL, is __________.

    N a. 75°00'W
    N b. 82°30'W
    Y c. 90°00'W
    N d. 97°30'W

1505: At 0000 you fix your position and change course to 090°T. At 0030 you again fix your position and it is 0.5 mile east of your DR. Which statement is TRUE?

    Y a. The current is easterly.
    N b. The drift is 0.5 knot.
    N c. You should alter course to the right to regain the track line.
    N d. The current is perpendicular to your track line.

1529: Widely spaced isobars on a weather map indicate __________.

    N a. high winds
    Y b. gentle breezes
    N c. ice, snow or frozen rain
    N d. probability of tornados

1609: A rapid rise or fall of the barometer indicates __________.

    N a. heavy rain within six hours
    N b. a decrease in wind velocity
    Y c. a change in the present weather conditions
    N d. that fog will soon set in

1626: Which instrument is used to measure the relative humidity of the air?

    N a. A hydrometer
    Y b. A hygrometer
    N c. A spectrometer
    N d. A barograph

1654: Which weather element cannot be measured accurately while on board a moving vessel?

    Y a. Visibility
    N b. Temperature
    N c. Wind direction
    N d. Atmospheric pressure

1691: Which of the following is associated with consistently high barometric pressure?

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

1691: Which of the following is associated with consistently high barometric pressure?

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

1706: In the Northern Hemisphere a wind is said to veer when the wind __________.

    Y a. changes direction clockwise, as from north to east, etc.
    N b. changes direction violently and erratically
    N c. remains constant in direction and speed
    N d. changes direction counterclockwise, as from south to east, etc.

1782: You are on course 027°T and take a relative bearing to a lighthouse of 220°. What is the true bearing to the lighthouse?

    N a. 113°
    N b. 193°
    Y c. 247°
    N d. 279°

1787: What indicates that a tropical cyclone may be within 500 to 1,000 miles of your position?

    Y a. A pumping of the barometer up and down a few millibars
    N b. A sudden wind shift from southwest to northwest followed by steadily increasing winds
    N c. The normal swell pattern becoming confused, with the length of the swell increasing
    N d. An overcast sky with steadily increasing rain from nimbostratus clouds

1804: Magnetic information on a chart may be __________.

    N a. found in the center(s) of the compass rose(s)
    N b. indicated by isogonic lines
    N c. found in a note on the chart
    Y d. All of the above

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.

2058: Illustration D038NG represents a fixed C of E lock and dam. What navigational light(s) is(are) exhibited at the position indicated by the letter D in the illustration? (D038NG )

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

2142: Which lights would you see on the Illinois waterway when any wickets of the dam or bear traps are open, or partially open, which may cause a set in the current conditions in the upper lock approach?

    N a. Green over amber (yellow)
    Y b. Red over amber (yellow)
    N c. Red over blue
    N d. Green over red

2328: Universal time (UTI) is another name for __________.

    N a. sidereal time
    Y b. Greenwich mean time
    N c. ephemeris time
    N d. atomic time

2352: When a superior planet is at 90° elongation, it is also at __________.

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

2435: What is a lighted safe water mark fitted with to aid in its identification?

    N a. A red and white octagon
    N b. Red and white retroreflective material
    N c. A sequential number
    Y d. A spherical topmark

2676: The place where a channel moves from along one bank of the river over to the other bank of the river is called a __________.

    N a. draft
    N b. cutoff
    N c. draw
    Y d. crossing

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

2709: Under the IALA-B Buoyage System, when entering from seaward a lateral system buoy to be left to port may display which of the topmarks shown? (D046NG )

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

2929: On 29 June 1981 you observe a back sight of the lower limb of the Moon. The sextant altitude (hs) is 114°16.9'. The height of eye is 36 feet and the index error is 2.0' on the arc. The horizontal parallax is 60.5'. What is the observed altitude (Ho)?

    Y a. 66°31.6'
    N b. 66°31.0'
    N c. 66°28.8'
    N d. 66°26.0'

2989: On 13 November 1981 you observe a back sight of the lower limb of the Moon. The sextant altitude (hs) is 110°31.2'. The height of eye is 46 feet and the index error is 2.0' off the arc. The horizontal parallax is 61.3'. What is the observed altitude (Ho)?

    N a. 70°41.4
    N b. 70°15.4'
    Y c. 70°11.4'
    N d. 70°02.2

3053: The vertical distance from the tidal datum to the level of the water is the __________.

    Y a. height of tide
    N b. range of tide
    N c. actual water depth
    N d. charted depth