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.


65: The LMT of LAN is 1210. Your longitude is 70°30'E. Which time would you use to enter the Nautical Almanac to determine the declination of the Sun at LAN?


83: All Loran-C transmitting stations are equipped with cesium frequency standards which permit __________.


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 __________.


104: What should you apply to a fathometer reading to determine the depth of water?

    N a. Subtract the draft of the vessel.
    Y b. Add the draft of the vessel.
    N c. Subtract the sea water correction .
    N d. Add the sea water correction.

188: Off Barnegat, NJ, with the wind coming out of the east, the wind-driven current will be flowing approximately __________.

    N a. 286°
    Y b. 254°
    N c. 106°
    N d. 016°

188: Off Barnegat, NJ, with the wind coming out of the east, the wind-driven current will be flowing approximately __________.

    N a. 286°
    Y b. 254°
    N c. 106°
    N d. 016°

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.

211: The light rhythm of Morse (A) is shown on __________.

    N a. preferred-channel buoys
    N b. starboard- or port-side buoys
    N c. special marks
    Y d. safe water buoys

323: The position accuracy of Loran-C degrades with increasing distance from the transmitting stations as __________.

    N a. gains are made over the signal path
    Y b. a result of variation in propagation conditions
    N c. the frequency of the pulses increases
    N d. the stations shift pulses

360: The Illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "M" represents __________. (D042NG )

    N a. rain
    Y b. snow
    N c. hail
    N d. ice

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

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

457: Find the height of the tide at Port Wentworth, GA, on 5 October 1983, at 1840 DST (ZD +4).

    N a. 3.0 feet
    N b. 3.5 feet
    N c. 4.0 feet
    Y d. 4.4 feet

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

471: Yellow lights may appear on __________.

    Y a. special purpose buoys
    N b. vertically-striped buoys
    N c. horizontally-banded buoys
    N d. spherical buoys

546: If it is impossible to avoid a hurricane in the Northern Hemisphere, the most favorable place to be when the storm passes is in __________.

    N a. the dangerous semicircle
    N b. the eye (center) of the storm
    N c. that half of the storm lying to the right of the storm's path
    Y d. that half of the storm lying to the left of the storm's path

581: The Captain of the Port has closed to navigation, and buoyed, a section of a harbor. These buoys would be painted __________.

    N a. red or green to conform with the other lateral aids
    N b. red and green horizontally-striped
    N c. solid yellow
    Y d. white with orange markings

583: The radar control used to reduce sea return at close ranges is the __________.

    N a. gain control
    Y b. sensitivity time control
    N c. fast time constant
    N d. pulse length control

648: Weather systems in the middle latitudes generally travel from __________.

    N a. north to south
    Y b. west to east
    N c. east to west
    N d. None of the above

673: You are underway at 5 knots and see on your radar a contact 10 miles directly astern of you. 12 minutes later, the contact is 8 miles directly astern of you. What is the estimated speed of the contact?

    N a. Dead in the water
    N b. 1 knot
    N c. 10 knots
    Y d. 15 knots

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

716: Standard atmospheric pressure in inches of mercury is __________.

    N a. 30.00
    N b. 28.92
    Y c. 29.92
    N d. 29.00

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°

826: In the U.S., in which direction do air masses usually move?

    Y a. Easterly
    N b. Southerly
    N c. Northerly
    N d. Southwesterly

872: Which agency publishes the Light Lists?

    Y a. United States Coast Guard
    N b. National Ocean Service
    N c. Oceanographic Office
    N d. Army Corps of Engineers

877: Cold water flowing southward through the western part of the Bering Strait between Alaska and Siberia is joined by water circulating counterclockwise in the Bering Sea to form the __________.

    N a. Alaska Current
    N b. Subarctic Current
    N c. Kuroshio Current
    Y d. Oyashio Current

911: Under the IALA-B Buoyage System, a buoy displaying a red light will __________.

    Y a. be left to starboard when entering from seaward
    N b. show a light characteristic of Morse Code "A"
    N c. be lettered
    N d. have a radar reflector

915: The Sun's center may be coincident with both the celestial equator and the observer's prime vertical circle when __________.

    N a. it crosses the December solstitial point
    N b. it crosses the June solstitial point
    N c. it is in upper transit
    Y d. its declination is zero

939: That half of the hurricane to the right hand side of its track (as you face the same direction that the storm is moving) in the Northern Hemisphere is called the __________.

    N a. windward side
    N b. leeward side
    N c. safe semicircle
    Y d. dangerous semicircle

944: High clouds, composed of small white flakes or scaly globular masses, and often banded together to form a "mackerel sky", would be classified as __________.

    N a. cirrus
    Y b. cirrocumulus
    N c. altostratus
    N d. cumulonimbus

958: You are preparing a weather report form. Twenty-five percent of the sky is covered with clouds, and the anemometer indicates that the apparent wind is from 062° relative at 13 knots. You are on course 238°T at 22 knots. How should you encode group Nddff? (D041NG )

    Y a. 20220
    N b. 20613
    N c. 30219
    N d. 32413

968: The world is divided into NAVAREAS for the dissemination of important marine information. Which NAVAREAS include the U.S. coasts?

    N a. I and II
    Y b. IV and XII
    N c. V and X
    N d. VI and VII

983: Error may be introduced into a magnetic compass by __________.

    N a. making a structural change to the vessel
    N b. a short circuit near the compass
    N c. belt buckles
    Y d. All of the above

1002: What publication contains information about the port facilities in Cadiz, Spain?

    Y a. World Port Index
    N b. United States Coast Pilot
    N c. Nautical Index
    N d. Sailing Directions

1033: Deviation which is maximum on intercardinal compass headings may be removed by the __________.

    N a. Flinders bar
    N b. transverse magnets
    N c. fore-and-aft magnets
    Y d. soft iron spheres on the sides of the compass

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

1074: As the temperature for a given mass of air increases, the __________.

    N a. dew point increases
    N b. dew point decreases
    N c. relative humidity increases
    Y d. relative humidity decreases

1167: The velocity of the current in large coastal harbors is __________.

    N a. unpredictable
    Y b. predicted in Tidal Current Tables
    N c. generally constant
    N d. generally too weak to be of concern

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

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

1337: What will be the time of maximum flood current at Sagamore Bridge on the Cape Cod Canal during the morning of 6 December 1983 (ZD +5)?

    Y a. 0708
    N b. 0712
    N c. 0716
    N d. 1020

1486: Which condition would most likely result in fog?

    Y a. Warm moist air blowing over cold water
    N b. Airborne dust particles
    N c. Warm moist air blowing over warm water
    N d. Dew point falling below the air temperature

1729: The first cloud formations you can use to indicate the bearing of the center of a hurricane or tropical storm are __________.

    Y a. the point of convergence of the cirrus clouds
    N b. the direction of movement of thunderstorms on radar
    N c. the darkest point of the clouds in the "bar" of the storm
    N d. the point of origin of the altostratus clouds

1752: What is the major limitation in using the Sight Reduction Tables for Air Navigation Volume I (Pub. No. 249) for star sights?

    N a. More accuracy is needed for celestial observations on board ship than what is tabulated.
    N b. Sights must be made at even time increments to benefit from the tables.
    Y c. Only certain stars are included and sights must be limited to those stars.
    N d. Only first magnitude stars are tabulated.

1910: What sextant correction corrects the apparent altitude to the equivalent reading at the center of the Earth?

    N a. Phase
    Y b. Parallax
    N c. Semidiameter
    N d. Augmentation

1919: The nadir is the point on the celestial sphere that is __________.

    N a. 90° away from the zenith
    N b. over Greenwich
    N c. on the western horizon
    Y d. directly below the observer

1944: In the horizon system of coordinates what is the equivalent to the celestial equator of the celestial equator system?

    Y a. Horizon
    N b. Prime vertical circle
    N c. Prime meridian
    N d. Principal vertical circle

2098: 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 magnets
    Y c. Fore-and-aft magnets
    N d. Athwartships magnets

2230: A nautical mile is a distance of approximately how much greater than or less than a statute mile?

    N a. 1/4 less
    N b. 1/7 less
    N c. 1/4 greater
    Y d. 1/7 greater

2379: The winter solstice is the point where the Sun is at __________.

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

2408: What is the equivalent of 42 min. 48 sec. in arc units?

    N a. 21°24'
    N b. 18°16'
    N c. 11°19'
    Y d. 10°42'

2432: A time diagram is a diagram of the celestial sphere as observed from above the __________.

    Y a. south celestial pole
    N b. north celestial pole
    N c. observer's meridian
    N d. Greenwich meridian

2494: You must construct a Mercator plotting sheet on a piece of paper measuring 24" by 30". The area includes latitude 28°N to 35°N and longitude 175°E to 178°W. Allow a three-quarter inch neat line on all sides. What is the maximum distance between each degree of longitude that will permit the area of the plotting sheet to be drawn within the stated limitation?

    N a. 3.40 inches
    Y b. 3.22 inches
    N c. 3.03 inches
    N d. 2.91 inches

2548: On the Mississippi River, gage zero is the gage reading measured from the __________.

    Y a. National Geodetic Vertical Datum
    N b. low water reference plane
    N c. the lowest recorded river depth
    N d. the highest recorded river depth

2688: The 10-cm radar as compared to a 3-cm radar of similar specifications will __________.

    N a. be more suitable for river and harbor navigation
    N b. provide better range performance on low lying targets during good weather and calm seas
    Y c. have a wider horizontal beam width
    N d. have more sea return during rough sea conditions

2764: You are in a channel inbound from sea. A daymark used to mark a channel junction when the preferred channel is to port will have the shape indicated by what letter in illustration D045NG?

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

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

2949: On 13 November 1981 you observe a back sight of the upper limb of the Sun. The sextant altitude (hs) is 109°26.3'. The height of eye is 66 feet, and the index error is 2.0' on the arc. What is the observed altitude (HO)?

    N a. 70°56.6'
    N b. 70°38.0'
    Y c. 70°27.2'
    N d. 70°23.2'

2986: Some places maintain a zone time of -13. What are the time and date at Greenwich if the zone time and date are 2152, 10 January?

    N a. 1052, 9 January
    Y b. 0852, 10 January
    N c. 1052, 10 January
    N d. 1052, 11 January

3116: With respect to automatic identification systems (AIS), which information is expected to be broadcast every 1 to 10 seconds?

    N a. Name of ship
    Y b. Ship's heading
    N c. IMO number
    N d. Vessel's draft