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.


3: Blinking of a Loran-C signal indicates __________.


92: When utilizing a Pacific Coast chart, the reference plane of soundings is __________.


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


184: When the index and horizon mirrors of a properly adjusted sextant are at an angle of 45° to each other, the arc reads __________.

    N a. 22 1/2°
    N b. 45°
    N c. 60°
    Y d. 90°

202: On charts of U.S. waters, a magenta marking is NOT used for marking a __________.

    N a. radio beacon
    N b. lighted buoy
    N c. prohibited area
    Y d. 5-fathom curve

286: On the pole side of the trade wind belt, there is an area of high pressure with weak pressure gradients and light, variable winds. This area is called the __________.

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

321: Which buoy may be even numbered?

    N a. Mid-channel buoy
    Y b. Unlighted nun buoy
    N c. Lighted green buoy
    N d. All of the above

394: An instrument designed to maintain a continuous record of atmospheric pressure is a(n) __________.

    N a. mercurial barometer
    N b. aneroid barometer
    Y c. barograph
    N d. thermograph

406: Your vessel is on course 135°T, speed 18 knots. From the appearance of the sea you estimate the speed of the true wind as 24.5 knots. The apparent wind is 40° on the starboard bow. Determine the speed of the apparent wind.

    N a. 24.2 knots
    N b. 28.4 knots
    N c. 32.2 knots
    Y d. 36.0 knots

535: The tropical year differs from which year by 20 minutes?

    N a. Astronomical year
    N b. Natural year
    N c. Equinoctial year
    Y d. Sidereal year

541: A yellow buoy may mark a(n) __________.

    N a. wreck
    N b. shoal area
    Y c. anchorage area
    N d. middle ground

559: A great circle crosses the equator at 162°E. It will also cross the equator at what other longitude?

    N a. 62°E
    N b. 126°W
    N c. 162°W
    Y d. 18°W

689: What is the index error of sextant C? (D050NG )

    Y a. 0'20" on the arc
    N b. 1'00" on the arc
    N c. 2'00" on the arc
    N d. 5'10" on the arc

690: What level of development of a tropical cyclone has a hundred mile radius of circulation, gale force winds, less than 990 millibars of pressure and vertically formed cumulonimbus clouds?

    N a. A tropical disturbance
    N b. A tropical depression
    Y c. A tropical storm
    N d. A typhoon

736: A line on a weather chart connecting places which have the same barometric pressure is called an __________.

    N a. isotherm
    N b. isallobar
    Y c. isobar
    N d. isotope

775: A sidereal day is shorter than a solar day. This difference is due to __________.

    N a. irregularities in the daily rotational rate of the Sun
    N b. the space motion of the solar system
    N c. the precession of the equinoxes
    Y d. the use of different reference points

777: With respect to a reversing current, slack water occurs when there is __________.

    Y a. little or no horizontal motion of the water
    N b. little or no vertical motion of the water
    N c. a weak ebb or flood current
    N d. when winds cause water to back up in a river mouth

827: The Benguela Current flows in a __________.

    N a. SW'ly direction along the NW coast of Africa
    N b. S'ly direction off the East Coast of Australia
    Y c. NW'ly direction along the SW coast of Africa
    N d. SW'ly direction along the SE coast of Greenland

881: Under the IALA-A Buoyage System, when entering from seaward, a buoy indicating the preferred channel is to starboard may have a __________.

    N a. green light
    N b. long-flashing light characteristic
    Y c. square topmark
    N d. conical shape

896: The wind direction around a low pressure area in the Northern Hemisphere is __________.

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

942: Light Lists for coastal waters are __________.

    N a. published every year and require no corrections
    N b. published every second year and must be corrected
    N c. published every five years and require no correction
    Y d. accurate thru NM number on title page and must be corrected

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

1037: Generally speaking, a ship steaming across the North Pacific from Japan to Seattle is likely to experience __________.

    N a. adverse currents for practically the entire crossing
    Y b. favorable currents for practically the entire crossing
    N c. favorable currents in the summer months and adverse currents in the winter months
    N d. variable currents having no significant effect on the total steaming time

1072: What is the approximate geographic range of Assateague Light, VA, if your height of eye is 52 feet (15.8 meters)? Refer to "Reprints from the LIGHT LISTS AND COAST PILOTS" .

    N a. 14.1 nm
    N b. 21.8 nm
    Y c. 23.0 nm
    N d. 50.2 nm

1088: Which statement about an estimated position is TRUE?

    N a. It is more reliable than a fix based on radar bearings.
    Y b. It may be based on a single LOP or questionable data.
    N c. When a 3-LOP fix plots in a triangle, the center of the triangle is the estimated position.
    N d. It is usually based on soundings.

1196: In the Northern Hemisphere, gusty winds shifting clockwise, a rapid drop in temperature, thunderstorms or rain squalls in summer (frequent rain/snow squalls in winter) then a rise in pressure followed by clearing skies, indicate the passage of a(n) __________.

    N a. warm front
    N b. tropical cyclone
    N c. anticyclone
    Y d. cold front

1222: On entering from seaward, a starboard side daymark will __________.

    N a. show a fixed red light if lighted
    N b. show a Morse (A) white light
    N c. be square in shape
    Y d. have an even number if numbered

1273: Deviation changes with a change in __________.

    N a. latitude
    Y b. heading
    N c. longitude
    N d. sea conditions

1273: Deviation changes with a change in __________.

    N a. latitude
    Y b. heading
    N c. longitude
    N d. sea conditions

1286: Which condition will occur after a cold front passes?

    N a. Temperature rises
    N b. Stratus clouds form
    N c. Pressure decreases
    Y d. Humidity decreases

1295: The best estimate of the wind direction at sea level can be obtained from observing the direction of the __________.

    N a. cloud movement
    N b. vessel heading
    Y c. waves
    N d. swells

1295: The best estimate of the wind direction at sea level can be obtained from observing the direction of the __________.

    N a. cloud movement
    N b. vessel heading
    Y c. waves
    N d. swells

1344: Which of the buoy symbols shown indicates a safe water mark? (D032NG )

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

1373: The reaction of a gyrocompass to an applied force is known as __________.

    Y a. precession
    N b. earth rate
    N c. gyroscopic inertia
    N d. gravity effect

1439: The symbols shown are used on radio facsimile weather charts. The symbol indicated at letter "G" represents a __________. (D042NG )

    N a. weather boundary
    N b. thunderstorm
    N c. wide spread sandstorm
    Y d. severe, line squall

1487: At the approaches to Savannah, GA, with the wind coming out of the west, the wind-driven current will be flowing approximately __________.

    Y a. 080°
    N b. 100°
    N c. 260°
    N d. 280°

1545: The change in the length of day becomes greater as latitude increases because of the __________.

    N a. inclination of the diurnal circle to the equator
    N b. decreasing distance between the terrestrial meridians
    Y c. increased obliquity of the celestial sphere
    N d. changing distance between the earth and the sun

1551: In order to get the maximum benefit from the Gulf Stream, on a voyage between Houston and Philadelphia, you should navigate __________.

    Y a. about 75 miles east of Ormond Beach, FL
    N b. close inshore between Jupiter Inlet and Fowey Rocks, FL
    N c. along the 50-fathom curve while off the east coast of Florida
    N d. about 10 miles east of Cape Canaveral, FL

1599: The time interval between successive wave crests is called the __________.

    N a. trough
    Y b. period
    N c. frequency
    N d. epoch

1632: Lighted white and orange buoys must show which color light?

    N a. Orange
    N b. Red
    Y c. White
    N d. Alternating yellow and white

1700: Generally speaking, you should expect to find low atmospheric pressure prevailing in the earth's __________.

    Y a. equatorial area
    N b. polar regions
    N c. mid-latitudes
    N d. All of the above

1923: Little or no change in the barometric reading over a twelve hour period indicates __________.

    N a. stormy weather is imminent
    Y b. that present weather conditions will continue
    N c. a defect in the barometer
    N d. increasing wind strength

1958: The spinning of a celestial body about its axis is known as __________.

    Y a. rotation
    N b. revolution
    N c. space motion
    N d. nutation

1961: What kind of pressure systems travel in tropical waves?

    N a. Subsurface pressure
    N b. Terrastatic pressure
    N c. High pressure
    Y d. Low pressure

2049: At morning stars, the first stars that should be observed are those with an azimuth in which quadrant?

    Y a. Eastern
    N b. Southern
    N c. Western
    N d. Northern

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

2140: The visible range marked on charts for lights is the __________.

    N a. minimum distance at which the light may be seen with infinite visibility
    N b. minimum distance at which the light may be seen based on a 12 mile distance to visible horizon
    N c. maximum distance the light may be seen restricted by the height of the light and the curvature of the earth
    Y d. maximum distance at which a light may be seen in clear weather with 10 miles visibility

2266: It is difficult to determine which limb of the Moon is fully illuminated __________.

    N a. when the Moon is low in the sky at rising or setting
    N b. at the new Moon phase
    N c. when taking Moon sights during daylight
    Y d. when the terminator is nearly vertical

2306: In the North Sea area, you sight a buoy showing a quick white light with 9 flashes every 15 seconds. Which of the four topmarks shown would be fitted to the buoy? (D031NG )

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

2345: You should plot your dead reckoning position __________.

    N a. from every estimated position
    N b. every three minutes in pilotage waters
    N c. only in pilotage waters
    Y d. from every fix or running fix

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

2430: You are on course 222°T and take a relative bearing of a lighthouse of 025°. What is the true bearing to the lighthouse?

    N a. 197°
    Y b. 247°
    N c. 315°
    N d. 335°

2460: You are on course 344°T and take a relative bearing of a lighthouse of 270°. What is the true bearing to the lighthouse?

    N a. 016°
    N b. 074°
    N c. 090°
    Y d. 254°

2604: A sidereal day is approximately how much shorter than a solar day?

    Y a. 4 minutes
    N b. 8 minutes
    N c. 12 minutes
    N d. 16 minutes

2629: In both regions of the IALA buoyage system, which topmark is used on a special mark? (D022NG )

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

2669: Under the IALA Buoyage System, which topmark shown will be displayed on a safe water mark? (D023NG )

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

2739: A daymark used to indicate the starboard side of the channel when approaching from seaward will have the shape indicated by what letter in illustration D045NG?

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

2812: A line of position from a celestial observation is a segment of a __________.

    Y a. circle of equal altitude
    N b. parallel of declination
    N c. parallel of altitude
    N d. vertical circle

3020: A mooring buoy, if lighted, shows which color light?

    N a. Yellow
    Y b. White
    N c. Blue
    N d. Any color except red or green

3091: Which of the following must an ECDIS system be able to perform?

    N a. Conversion of "graphical coordinates" to "display coordinates"
    N b. Transformation of local datum to WGS-'84 datum
    N c. Calculation of true azimuth and distance between two geographical points
    Y d. All of the above