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.


50: The difference between the heights of low and high tide is the __________.


59: For navigational purposes, each great circle on the Earth has a length of __________.


156: In reading a weather map, closely spaced pressure gradient lines would indicate __________.


163: How many fixed objects are needed to plot a running fix?

    N a. None
    Y b. One
    N c. Two
    N d. Three

195: The equation of time is 8m 00s. The mean Sun is ahead of the apparent Sun. If you are 2°W of the central meridian of your time zone, when will the apparent Sun cross your meridian?

    Y a. 1216
    N b. 1208
    N c. 1200
    N d. 1152

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

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

242: The difference between the heights of low and high tide is the __________.

    Y a. range
    N b. period
    N c. depth
    N d. distance

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

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

404: An aneroid barometer is an instrument __________.

    N a. used to measure the speed of wind
    Y b. in which the pressure of the air is measured
    N c. that tells which direction a storm is coming from
    N d. used to measure the height of waves

436: A wind vane on a moving vessel shows __________.

    N a. dead reckoning wind direction
    N b. true wind direction
    Y c. apparent wind direction
    N d. estimated wind direction

495: A semidiameter correction is applied to observations of __________.

    N a. Mars
    Y b. the Moon
    N c. Jupiter
    N d. All of the above

536: You are enroute from Puerto Rico to New York. A hurricane makes up and is approaching. If the wind veers steadily, this indicates that your vessel is __________.

    Y a. in the dangerous semicircle
    N b. in the navigable semicircle
    N c. directly in the path of the storm
    N d. in the storm center

687: The drift and set of tidal, river, and ocean currents refer to the __________.

    N a. position and area of the current
    Y b. speed and direction toward which the current flows
    N c. type and characteristic of the current's flow
    N d. None of the above

709: A sea breeze is a wind __________.

    N a. that blows towards the sea at night
    Y b. that blows towards an island during the day
    N c. caused by cold air descending a coastal incline
    N d. caused by the distant approach of a hurricane

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

844: A cloud of marked vertical development (often anvil-shaped) would be classified as __________.

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

853: The standard magnetic compass heading differs from the true heading by __________.

    Y a. compass error
    N b. latitude
    N c. variation
    N d. deviation

854: The appearance of nimbostratus clouds in the immediate vicinity of a ship at sea would be accompanied by which of the following conditions?

    Y a. Rain and poor visibility
    N b. Dropping barometric pressure and backing wind in the Northern Hemisphere
    N c. High winds and rising sea
    N d. Severe thunderstorms

949: In Region A of the IALA Buoyage System, when entering from seaward, the port side of a channel would be marked by a __________.

    N a. black can buoy
    Y b. red can buoy
    N c. black conical buoy
    N d. red conical buoy

952: What is TRUE concerning new editions of Light Lists?

    N a. Supplements to new editions are issued monthly by the U.S. Coast Guard.
    N b. New editions are published by the National Ocean Service.
    Y c. New editions are corrected through the date shown on the title page.
    N d. None of the above

992: Which publication contains information on Naval Control of Shipping (NCS) in time of emergency or war?

    Y a. Pub. 117, Radio Navigational Aids
    N b. Appropriate volume of the Sailing Directions
    N c. Pub. 102, International Code of Signals
    N d. Light List

1053: Before a magnetic compass is adjusted certain correctors must be checked to ensure that they are free of permanent magnetism. These correctors are the __________.

    N a. fore-and-aft and athwartships magnets
    N b. dip needle and heeling magnet
    N c. heeling magnet and Flinders bar
    Y d. Flinders bar and quadrantal spheres

1057: One of the causes of ocean currents is density differences in the water. This is true because __________.

    N a. in an area of high density the water's surface is lower than in an area of low density
    Y b. surface water flows from an area of high density to one of low density
    N c. the lesser the density gradient the freer the water is to move
    N d. it is the density differences that cause the currents to stay in the troughs

1057: One of the causes of ocean currents is density differences in the water. This is true because __________.

    N a. in an area of high density the water's surface is lower than in an area of low density
    Y b. surface water flows from an area of high density to one of low density
    N c. the lesser the density gradient the freer the water is to move
    N d. it is the density differences that cause the currents to stay in the troughs

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.

1162: A line connecting all possible positions of your vessel at any given time is a __________.

    N a. longitude line
    N b. latitude line
    Y c. line of position
    N d. fix

1257: What will be the velocity of the tidal current 1.0 mile southwest of Lewis Pt., RI, at 1501 EST (ZD +5) on 4 April 1983?

    Y a. 0.7 knot
    N b. 1.4 knots
    N c. 1.6 knots
    N d. 1.9 knots

1259: General information on enroute weather and climate is found in __________.

    Y a. the Sailing Directions and the Coast Pilot
    N b. a weather fax
    N c. the Local Notice to Mariners
    N d. the Light List

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

1517: When determining compass error by an azimuth of Polaris, you enter the Nautical Almanac with the __________.

    N a. GHA Aries
    Y b. LHA Aries
    N c. LHA Polaris
    N d. GHA Polaris

1557: A Doppler log in the volume reverberation mode indicates __________.

    N a. speed being made good
    Y b. speed through the water
    N c. the set of the current
    N d. the depth of the water

1624: A psychrometer has two thermometers that provide dry bulb and wet bulb temperatures. By comparing these two temperature readings with a set of tables you can determine the __________.

    N a. atmospheric pressure
    N b. wind speed
    Y c. relative humidity and dew point
    N d. wind chill factor

1657: Fog is formed when __________.

    N a. the moisture in the air is condensed into small droplets
    N b. air is cooled to its dew point
    N c. the base of a cloud is on the ground
    Y d. All of the above

1658: Fog forms when the air temperature is at or below __________.

    N a. 32° F
    N b. the wet bulb temperature
    Y c. the dew point
    N d. the dry bulb temperature

1675: You are entering port and have been instructed to anchor, as your berth is not yet available. You are on a SW'ly heading, preparing to drop anchor, when you observe the range lights as shown on your starboard beam. You should __________. (D047NG )

    N a. NOT drop the anchor until the lights are in line
    Y b. ensure your ship will NOT block the channel or obstruct the range while at anchor
    N c. drop the anchor immediately as the range lights mark an area free of obstructions
    N d. drop the anchor immediately as a change in the position of the range lights will always be an indication of dragging anchor

1769: Under the numbering system used by NGA (NIMA), a three digit number may be used for __________.

    Y a. a small scale chart depicting a major portion of an ocean basin or a position plotting sheet
    N b. non-navigational materials such as radar plotting sheets
    N c. products issued periodically such as the Notice to Mariners
    N d. large scale charts of areas that are infrequently used for navigation such as the headwaters of rivers

1770: A Doppler speed log indicates speed over ground __________.

    N a. at all times
    Y b. in the bottom return mode
    N c. in the volume reverberation mode
    N d. only when there is no current

1852: When plotting a circle of equal altitude for a high altitude sight, the radius of the circle is determined by the formula __________.

    Y a. 90° - Ho
    N b. 180° - GHA
    N c. GHA - LHA
    N d. z - d

1905: In order to insure that the racon signal is visible on your 3 cm radar, the __________.

    N a. 10 cm radar should be placed on standby or turned off
    N b. gain control should be turned to maximum
    N c. radar should be stabilized, head up
    Y d. rain clutter control should be off but, if necessary, may be on low

1946: When making landfall at night, you can determine if a light is a major light or an offshore buoy by __________.

    N a. the intensity of the light
    Y b. checking the period and characteristics against the Light List
    N c. the color, because the buoy will have only a red or a green light
    N d. Any of the above can be used to identify the light.

1979: The principal vertical circle is that great circle on the celestial sphere that passes through the __________.

    N a. zenith and the celestial body
    Y b. zenith and the north and south poles
    N c. poles and Greenwich
    N d. zenith and is parallel to the horizon

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°

2183: 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 D if the lock walls and piers are not awash?

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

2232: A vessel is heading magnetic north and its magnetic compass indicates a heading of 003°. Which action should be taken to remove this error during compass adjustment?

    N a. If the red ends are to starboard you should raise the athwartships tray.
    Y b. If the red ends are to starboard, and the athwartships tray is at the bottom, you should remove some magnets.
    N c. If the red ends are to port, and the athwartships tray is at the top, you should reverse the magnets.
    N d. If the red ends are to port, and the athwartships tray is at the top, you should lower the tray.

2309: The plane of the ecliptic is inclined to the plane of the celestial equator by what angle?

    N a. 00°23'
    Y b. 23°27'
    N c. 45°00'
    N d. 90°00'

2342: What happens because of augmentation?

    Y a. The Moon appears larger as the elevation increases.
    N b. The Sun appears larger when viewed against the darker background of the horizon.
    N c. The horizon appears elevated when observing a bright Sun or Moon at low altitudes.
    N d. The Moon appears larger at the full Moon.

2372: In the North Sea area, you sight a buoy showing a quick white light showing 6 flashes followed by one long flash at 15 second intervals. Which of the four topmarks illustrated in diagram D031NG would be fitted to this buoy? (D031NG )

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

2376: A large group of stars revolving around a center is known as a __________.

    N a. cluster
    N b. shower
    N c. constellation
    Y d. galaxy

2404: The dividing meridian between zone descriptions +7 and +8 is __________.

    N a. 105°00'W
    Y b. 112°30'W
    N c. 117°00'W
    N d. 120°30'W

2540: The distance between any two meridians measured along a parallel of latitude and expressed in miles is the __________.

    N a. difference in longitude
    N b. mid-longitude
    Y c. departure
    N d. meridian angle

2634: Under the U.S. Aids to Navigation System on the Western Rivers, a preferred-channel buoy is __________.

    Y a. horizontally-banded red and green
    N b. vertically-striped red and white
    N c. solid red
    N d. solid green

2694: What is the equivalent of 10°48' in time units?

    N a. 2 min. 39 sec.
    N b. 20 min. 12 sec.
    Y c. 43 min. 12 sec.
    N d. 50 min. 12 sec.

2706: The following types of vessels are awaiting lockage on the upper Mississippi. Which type of vessel is normally passed through the lock first?

    N a. Pleasure craft
    N b. Commercial towboats
    Y c. Commercial passenger vessels
    N d. Commercial fishing vessels

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

2866: Some locations maintain a zone time of -13. What are the zone time and date if the Greenwich time and date are 2152, 10 January?

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

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'

3093: ECDIS must have the capability to preserve the record of the track for the previous __________.

    N a. 4 hours
    N b. 6 hours
    Y c. 12 hours
    N d. 24 hours

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