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.


18: A vessel's position should be plotted using bearings of __________.


29: You are approaching a multiple-span bridge at night. The main navigational channel span will be indicated by __________.


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


164: The part of a sextant mounted directly over the pivot of the index arm is the __________.

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

178: You are steering a southerly course, and you note that the chart predicts an easterly current. Without considering wind, how may you allow for the set?

    Y a. Head your vessel slightly to the right
    N b. Head your vessel slightly to the left
    N c. Decrease your speed
    N d. Increase your speed

244: To make sure of getting the full advantage of a favorable current, you should reach an entrance or strait at what time in relation to the predicted time of the favorable current?

    N a. One hour after the predicted time
    N b. At the predicted time
    N c. 30 minutes before flood, one hour after an ebb
    Y d. 30 minutes before the predicted time

278: You are underway on course 050訊 and your maximum speed is 11 knots. The eye of a hurricane bears 070訊, 80 miles from your position. The hurricane is moving towards 270訊 at 19 knots. If you maneuver at 11 knots to avoid the hurricane, what could be the maximum CPA?

    N a. 84 miles
    N b. 79 miles
    N c. 74 miles
    Y d. 66 miles

444: A sylphon cell is a part of a __________.

    N a. maximum thermometer
    Y b. barograph
    N c. thermograph
    N d. hygrometer

445: The values of the Greenwich hour angle and declination, tabulated in all almanacs, are for the __________.

    N a. upper limb of a celestial body
    N b. lower limb of a celestial body
    Y c. centers of the various celestial bodies
    N d. lower limb of the Sun and Moon; center of the stars and planets

456: Which condition exists in the eye of a hurricane?

    N a. Wind rapidly changing direction
    N b. A temperature much lower than that outside the eye
    N c. Towering cumulonimbus clouds
    Y d. An extremely low barometric pressure

503: You are approaching a light fitted with a RACON. The light may be identified on the radar by __________.

    N a. a dashed line running from the center of the scope to the light
    N b. an audible signal when the sweep crosses the light
    N c. a circle appearing on the scope surrounding the light
    Y d. a coded signal appearing on the same bearing at a greater range than the light

539: You are underway on course 050訊 and your maximum speed is 13 knots. The eye of a hurricane bears 120訊, 100 miles from your position. The hurricane is moving towards 265訊 at 25 knots. What course should you steer at 13 knots to have the maximum CPA?

    Y a. 324訊
    N b. 306訊
    N c. 299訊
    N d. 276訊

574: If your mercurial barometer reads 30.50 inches (1033 millibars) and the temperature is 56蚌 (13蚓), what is the correct reading at 55衹, 150訖?

    N a. 30.42 inches (1030 millibars)
    Y b. 30.45 inches (1031 millibars)
    N c. 30.50 inches (1032 millibars)
    N d. 30.53 inches (1033 millibars)

589: What is the index error of sextant D? (D050NG )

    N a. 7'10" on the arc
    N b. 6'50" on the arc
    N c. 3'00" on the arc
    Y d. 2'10" on the arc

652: What agency of the U.S. Government issues charts of U.S. waters and Coast Pilots?

    Y a. National Ocean Service
    N b. National Imagery and Mapping Agency
    N c. U.S. Coast Guard
    N d. U.S. Naval Observatory

663: You are underway at 10 knots. At 1800 you note a radar contact dead ahead at a range of 10 miles. At 1812 the contact is dead ahead at a range of 8 miles. The estimated speed of the contact is __________.

    Y a. dead in the water
    N b. 5 knots
    N c. 10 knots
    N d. 15 knots

756: What is a common unit of measure for atmospheric pressure?

    N a. centimeters
    Y b. Inches
    N c. Degrees
    N d. Feet

823: The greatest directive force is exerted on the magnetic compass when the __________.

    N a. needles are nearly in line with the meridian
    N b. vessel is near the magnetic poles
    N c. variation is near zero
    Y d. vessel is near the magnetic equator

833: The magnetic compass magnets are acted on by the horizontal component of the Earth's total magnetic force. This magnetic force is GREATEST at the __________.

    N a. north magnetic pole
    N b. south magnetic pole
    N c. magnetic prime vertical meridian
    Y d. magnetic equator

910: 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 38 feet (11.6 meters) and the visibility is 5.5 miles. At what approximate range will you FIRST sight the light?

    N a. 5.5 miles
    N b. 6.3 miles
    Y c. 8.0 miles
    N d. 12.0 miles

1022: What is the approximate geographic range of Fenwick Island Light, Delaware, if your height of eye is 37 feet (11.6 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 24.8 nm
    Y b. 17.8 nm
    N c. 15.9 nm
    N d. 10.3 nm

1023: Which compensates for induced magnetism in the horizontal soft iron of a vessel?

    Y a. Iron spheres mounted on the binnacle
    N b. A single vertical magnet under the compass
    N c. The Flinders bar
    N d. Magnets in trays inside the binnacle

1030: You are preparing a weather report form, WS Form B-80. The dry bulb thermometer reads 78蚌, and the wet bulb thermometer reads 75蚌. How would you encode the air temperature groups in the report? (D041NG )

    Y a. 10256, 2023/
    N b. 10780, 2074/
    N c. 00256, 0023/
    N d. 10256, 2074/

1047: Which is NOT a contributing cause of ocean currents?

    N a. Surface winds
    N b. Density differences in the water
    N c. Underwater topography
    Y d. Gravitational effects of celestial bodies

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

1304: The distance to the nearest vertex from any point on a great circle track cannot exceed __________.

    Y a. 5400 nautical miles
    N b. 5840 nautical miles
    N c. 6080 nautical miles
    N d. 10,800 nautical miles

1329: Yesterday your chronometer read 03h 01m 56s at the 1500 GMT time tick. Today your chronometer read 03h 01m 54s at the 1500 GMT time tick. What is the chronometer rate?

    N a. 1m 54s fast
    N b. 2s fast
    Y c. -2s
    N d. +2s

1338: Which type of cloud is indicated by the number 6? (D039NG )

    N a. Altocumulus
    Y b. Stratocumulus
    N c. Altostratus
    N d. Cirrus

1386: The FIRST indications a mariner will have of the approach of a warm front will be __________.

    N a. large cumulonimbus clouds building up
    N b. low dark clouds with intermittent rain
    N c. fog caused by the warm air passing over the cooler water
    Y d. high clouds gradually followed by lower thicker clouds

1405: After Venus passes the point of greatest elongation east in its orbit, the first position in which the elongation will be zero is __________.

    N a. superior conjunction
    Y b. inferior conjunction
    N c. opposition
    N d. None of the above; the elongation will never be zero

1511: When within 300 miles of a named tropical storm or hurricane, it is standard practice to send weather reports every __________.

    N a. 8 hours
    N b. 6 hours
    Y c. 3 hours
    N d. hour

1524: A barometric pressure reading of 29.92 inches of mercury is equivalent to __________.

    Y a. 1013.25 millibars
    N b. 29.92 feet of water
    N c. 766 millimeters of mercury
    N d. 76 centimeters of water

1530: In shallow water, waves that are too steep to be stable, causing the crests to move forward faster than the rest of the wave, are called __________.

    N a. rollers
    Y b. breakers
    N c. white caps
    N d. surfers

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

1713: When a tornado moves over the water from land it is called a __________.

    N a. tornado
    Y b. waterspout
    N c. hurricane
    N d. cyclone

1759: Which magnetic compass corrector(s) can be set while the vessel is on a heading of magnetic north or magnetic south?

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

1773: A "Norther" in the Gulf of Mexico is __________.

    N a. a wind shift to the north accompanied by a drop in temperature
    N b. a forcible northerly wind of at least 20 knots
    N c. a strong northerly wind that generally occurs between November and March
    Y d. All of the above

1794: Why are low altitude sun sights not generally used?

    Y a. Errors due to unusual refraction may exist.
    N b. Sextants may have large errors at small angles of elevation.
    N c. Modern sight reduction tables are not complete for low altitudes below 5.
    N d. The glare on the horizon causes irradiation errors.

1888: What is the relative bearing of an object broad on the starboard bow?

    N a. 030
    Y b. 045
    N c. 060
    N d. 075

1984: When a dual purpose marking is used, the mariner following the Intracoastal Waterway should be guided by the __________.

    N a. color of the aid
    N b. shape of the aid
    N c. color of the top band
    Y d. shape of the yellow mark

2006: What is the relative bearing of an object broad on the port beam?

    N a. 315
    N b. 300
    Y c. 270
    N d. 235

2081: You are taking bearings on two known objects ashore. The BEST fix is obtained when the angle between the lines of position is __________.

    N a. 30
    N b. 45
    N c. 60
    Y d. 90

2188: A vessel is heading magnetic north and its magnetic compass indicates a heading of 003. What action should be taken to remove this error during compass adjustment?

    Y a. If the red ends are to starboard the athwartships magnets should be lowered.
    N b. If the blue ends are forward the fore-and-aft magnets should be raised.
    N c. If the red ends are to starboard and the tray is at the top add some athwartships magnets.
    N d. If the blue ends are aft the fore-and-aft magnets should be raised.

2312: Mars is only seen at two phases, one of which __________.

    Y a. is the full phase
    N b. is conjunction
    N c. occurs only at sunset or sunrise
    N d. occurs at or near 0 elongation

2330: You are heading in a northerly direction when you come across an easterly current. Your vessel will __________.

    Y a. be pushed to starboard
    N b. be pushed to port
    N c. decrease in engine speed
    N d. remain on course

2336: The period of revolution of the Moon is __________.

    N a. 24 hours
    Y b. about 27.3 days
    N c. 365 days
    N d. about 19 years

2384: On U.S. charts, you can tell if a named feature such as a rock (i.e. Great Eastern Rock in Block Island Sound) is submerged by the __________.

    N a. color of ink used to print the name
    Y b. style of type used to print the name
    N c. dashed circle around the feature
    N d. magenta circle around the feature

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

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

2696: You must draw a plotting sheet covering latitudes 52訕 to 56訕 and longitudes 179訖 to 175蚩. If the distance between latitude 52訕 to 56訕 is 24 inches, what is the distance between the meridians of 1 of longitude?

    N a. 3.2 inches
    Y b. 3.5 inches
    N c. 4.0 inches
    N d. 4.2 inches

2726: A daymark used as a special mark is indicated by which letter in the diagram? (D045NG )

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

2804: The altitude at LAN may be observed by starting several minutes in advance and continuing until a maximum altitude occurs. This procedure should not be used __________.

    N a. when the declination and latitude are of different names
    N b. when the declination is greater than and the same name as the latitude
    N c. if the vessel is stopped or making bare steerageway
    Y d. on a fast vessel on northerly or southerly headings

2878: Given are the courses and speeds of 4 vessels. The navigator of which vessel would be required to know the actual time of meridian transit in order to take an accurate observation at LAN?

    N a. C 356訊, Sp 5 knots
    N b. C 099訊, Sp 17 knots
    Y c. C 192訊, Sp 23 knots
    N d. C 278訊, Sp 6 knots

2932: If the main channel under a bridge is marked with lights of the lateral system the adjacent bridge piers should be marked with __________.

    N a. occulting white lights
    Y b. fixed yellow lights
    N c. fixed white lights
    N d. flashing yellow lights

2947: A position obtained by crossing lines of position taken at different times and advanced to a common time is a(n) __________.

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

2990: In which source could you find the vertical clearance of a bridge on the Ohio River?

    N a. Notice to Mariners
    Y b. Light List of the Mississippi River System
    N c. Great Lakes Pilot
    N d. Coast Pilot of the Gulf of Mexico

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

3085: An ECDIS is required to display which information?

    N a. Water temperature
    N b. Climatology data
    N c. Speed of advance
    Y d. Depth contours

3101: The typical operating range of automatic identification systems (AIS) at sea is nominally __________.

    N a. 2 nm
    N b. 8 nm
    Y c. 20 nm
    N d. 40 nm

3103: In general, on how many radio channels will an automatic identification system (AIS) operate?

    N a. 1
    Y b. 3
    N c. 4
    N d. 12