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.


5: A vessel is steaming in east longitude on January 25 and crosses the International Date Line on an eastbound course at 0900 zone time. What is the date and time at Greenwich when the vessel crosses the line?


135: The standard meridian for the time zone +1 is __________.


148: When possible, a DR plot should always be started from where?


149: You are underway on course 050°T and your maximum speed is 13 knots. The eye of a hurricane bears 100°T, 120 miles from your position. The hurricane is moving towards 275°T at 25 knots. What course should you steer at 13 knots to have the maximum CPA?

    N a. 339°
    Y b. 333°
    N c. 326°
    N d. 320°

158: Discounting slip, if your vessel is turning RPM for 10 knots and making good a speed of 10 knots, the current could be __________.

    N a. with you at 10 knots
    N b. against you at 10 knots
    Y c. slack
    N d. with you at 2 knots

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

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

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

200: When navigating using GPS, what is an indicator of the geometry of the satellites that your receiver is locked onto?

    Y a. Horizontal Dilution of Precision
    N b. Selective Availability
    N c. Doppler Shifting
    N d. Precision Coding

350: When making landfall at night, the light from a powerful lighthouse may sometimes be seen before the lantern breaks the horizon. This light is called the __________.

    N a. diffusion
    N b. backscatter
    Y c. loom
    N d. elevation

533: You are using a radar in which your own ship is shown at the center, and the heading flash always points to 0°. If bearings are measured in relation to the flash, what type of bearings are produced?

    Y a. Relative
    N b. True
    N c. Compass
    N d. Magnetic

553: The beam width of your radar is 2°. The left tangent bearing of a small island, as observed on the PPI scope, is 056°pgc. If the gyro error is 2°E, what bearing would you plot on the chart?

    N a. 052°
    N b. 056°
    Y c. 059°
    N d. 060°

613: Your radar indicates a target; however, there is no visible object at the point indicated. A large mountain, approximately 50 miles away on the same bearing as the target, is breaking the horizon. You should suspect the radar target is caused by __________.

    N a. a submerged submarine
    Y b. ducting
    N c. sub-refraction
    N d. ionospheric skip waves

626: What indicates the arrival of a hurricane within 24 to 36 hours?

    N a. The normal swell becoming lower and from a steady direction
    N b. Long bands of nimbostratus clouds radiating from a point over the horizon
    N c. The barometer drops 2 millibars between 1000 and 1600
    Y d. Unusually good weather with above average pressures followed by a slow fall of 4 millibars in six hours

688: In mid-ocean, the characteristics of a wave are determined by three factors. What is NOT one of these factors?

    Y a. Effect of the moon's gravity
    N b. Fetch
    N c. Wind velocity
    N d. Length of time a wind has been blowing

795: The path of a celestial body during its daily apparent revolution around the Earth is called its __________.

    N a. ecliptic
    Y b. diurnal circle
    N c. altitude circle
    N d. circle of position

810: The position labeled B is a(n) __________. (D051NG )

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

813: At the magnetic equator there is no induced magnetism in the vertical soft iron because __________.

    N a. the lines of force cross the equator on a 0°-180° alignment
    N b. the quadrantal error is 0°
    Y c. there is no vertical component of the Earth's magnetic field
    N d. the intercardinal headings have less than 1° error

815: When entering from seaward, a buoy displaying a composite group (2+1) flashing red light indicates __________.

    Y a. a junction with the preferred channel to the left
    N b. a sharp turn in the preferred channel to the right
    N c. the starboard side of the secondary channel
    N d. a wreck to be left on the vessel's port side

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

924: The form of cloud often known as "mackerel sky" which is generally associated with fair weather is __________.

    N a. nimbostratus
    N b. stratus
    Y c. cirrocumulus
    N d. cumulonimbus

956: Good weather is usually associated with a region of __________.

    N a. low barometric pressure
    Y b. high barometric pressure
    N c. falling barometric pressure
    N d. pumping barometric pressure

1004: A low, uniform layer of cloud resembling fog, but not resting on the ground, is called __________.

    N a. cumulus
    N b. nimbus
    Y c. stratus
    N d. cirrus

1054: The dry-bulb temperature is 78°F (26°C) and the wet-bulb temperature is 68°F (20°C). What is the relative humidity?

    N a. 10%
    N b. 24%
    N c. 56%
    Y d. 60%

1116: When a cold air mass and a warm air mass meet, and there is no horizontal motion of either air mass, it is called a(n) __________.

    N a. cold front
    N b. occluded front
    Y c. stationary front
    N d. warm front

1198: The Illustration shows the symbols used on radio facsimile weather charts. Which of these symbols indicates a dust storm? (D042NG )

    N a. I
    N b. H
    Y c. O
    N d. P

1215: Daylight savings time is a form of zone time that adopts the time __________.

    N a. two zones to the east
    N b. two zones to the west
    Y c. one zone to the east
    N d. one zone to the west

1242: Daymarks marking the starboard side of the channel when going towards the sea are __________.

    Y a. green squares
    N b. green triangles
    N c. red squares
    N d. red triangles

1323: The magnetic compass error which changes with the geographical location of your vessel is called __________.

    N a. deviation
    Y b. variation
    N c. compensation
    N d. differentiation

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

1380: Which type of weather could you expect soon after seeing "hook" or "comma" shaped cirrus clouds?

    Y a. Rain with the approach of a warm front
    N b. Clearing with the approach of a cold front
    N c. Continuing fog and rain
    N d. The formation of a tropical depression

1543: The distance between the surface of the water and the tidal datum is the __________.

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

1546: You are sailing south on the Intracoastal Waterway (ICW) when you sight a red nun buoy with a yellow triangle painted on it. Which statement is TRUE?

    N a. Geometric symbols such as squares and triangles replace letters and numbers on ICW aids to navigation.
    Y b. The ICW and another waterway coincide in this geographical area.
    N c. The yellow triangle identifies a sharp turn (over 60°) in the channel.
    N d. This is an information or regulatory buoy that also has lateral significance.

1615: The Illustration shows the symbols used on radio facsimile weather charts. Which symbol indicates snow? (D042NG )

    N a. G
    N b. H
    Y c. M
    N d. N

1616: Which picture in illustration D034NG shows a Morse (A) light? (D034NG )

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

1616: Which picture in illustration D034NG shows a Morse (A) light? (D034NG )

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

1662: Fog generally clears when the __________.

    N a. wind speed increases
    N b. wind direction changes
    N c. temperature increases
    Y d. All of the above

1680: A weather front exists when __________.

    N a. air masses of the same temperature meet
    Y b. air masses of different temperatures meet
    N c. many clouds create a differential in air density
    N d. two lows are separated by a ridge of higher pressure

1695: Compared to a low pressure system, generally the air in a high is __________.

    N a. warmer, less dense, and less stable
    Y b. cool, more dense, and drier
    N c. muggy and cloudy
    N d. extremely moist with high relative humidity

1760: A Doppler log in the bottom return mode indicates the __________.

    N a. velocity of the current
    N b. bottom characteristics
    N c. depth of the water
    Y d. speed over the ground

1875: The position labeled "E" was plotted because __________. (D051NG )

    N a. a dead reckoning position is plotted within a half-hour of each course change
    N b. the position is a running fix
    Y c. a dead reckoning position is plotted for each speed change
    N d. the vessel's position was fixed at 1145

1940: The diameter of the Sun and Moon as seen from the Earth varies slightly but averages about __________.

    N a. 1'
    N b. 52'
    Y c. 32'
    N d. 15.5'

2021: While on watch, you notice that the air temperature is dropping and is approaching the dew point. Which type of weather should be forecasted?

    N a. Hail
    N b. Heavy rain
    N c. Sleet
    Y d. Fog

2114: Vessels regularly navigating rivers above Cairo, Illinois, shall at all times have on board a copy of __________.

    N a. Sailing Directions
    N b. Nautical Almanac for the year
    N c. U.S. Coast Pilot
    Y d. U.S. Army Corps of Engineers Regulations (Blue Book)

2119: Which stock number indicates an NGA (NIMA) chart designed for fixing positions at sea and DR plotting while on a long voyage?

    Y a. WOAGN520
    N b. PILOT16
    N c. 16BCO16212
    N d. WOPZC5245

2178: The Flinders bar and the quadrantal spheres should be tested for permanent magnetism at what interval?

    N a. They are not subject to permanent magnetism; no check is necessary.
    N b. Semiannually
    Y c. Annually
    N d. Every five years

2290: Magnets in the binnacles of magnetic compasses are used to reduce the effect of __________.

    Y a. deviation
    N b. variation
    N c. local attraction
    N d. All of the above

2402: You have completed the magnetic compass adjustments on magnetic east and magnetic south. The vessel is now steady on magnetic north but the compass reads 356°. You should now adjust the compass until it reads __________.

    Y a. 358°
    N b. 000°
    N c. 002°
    N d. 004°

2508: Normal pool elevation is the height in feet of the section of river above a dam. This height is measured from __________.

    N a. low steel on the Huey P. Long Bridge
    Y b. mean sea level
    N c. the local water table
    N d. the minimum dam control level

2538: The light characteristic of composite group flashing (2 + 1) is used in the Aids to Navigation System on the Western Rivers for lights on __________.

    N a. the right descending bank
    N b. the left descending bank
    Y c. preferred-channel buoys
    N d. daymarks with no lateral significance

2579: A phase correction may be applicable to correct the sextant altitude correction of __________.

    N a. any star
    N b. the Sun
    N c. third magnitude stars only
    Y d. some planets

2587: 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?

    Y a. C 166°T, Sp 24 knots
    N b. C 013°T, Sp 7 knots
    N c. C 291°T, Sp 25 knots
    N d. C 112°T, Sp 4 knots

2592: A deadhead is a(n) __________.

    Y a. tree or log awash in a nearly vertical position
    N b. crew member who refuses to work
    N c. upstream end of a land wall
    N d. buoy that is adrift

2618: You must draw a plotting sheet covering latitudes 38°N to 43°N and longitudes 179°E to 178°W. If the distance between each degree of longitude is 5 inches, what is the distance between latitude 38°N and latitude 43°N?

    N a. 29.0 inches
    N b. 29.6 inches
    N c. 32.1 inches
    Y d. 32.8 inches

2639: Under the U.S. Aids to Navigation System used on the Western Rivers, aids to navigation lights on the right descending bank show __________.

    Y a. white or green lights
    N b. white or red lights
    N c. green lights only
    N d. white lights only

2683: A vessel's position should be plotted using bearings of __________.

    N a. buoys close at hand
    Y b. fixed known objects on shore
    N c. fixed objects
    N d. All of the above

3003: The height of tide is the __________.

    Y a. difference between the depth of the water and the area's tidal datum
    N b. depth of water at a specific time due to tidal effect
    N c. difference between the depth of the water and the high water tidal level
    N d. difference between the depth of the water at high tide and the depth of the water at low tide

3011: The survey information upon which a chart is based is found __________.

    N a. at the top center of the next line
    Y b. near the chart title
    N c. at the lower left corner
    N d. at any convenient location

3042: How long would a steady wind need to blow in order to create a wind driven current?

    N a. 2 hours
    N b. 6 hours
    Y c. 12 hours
    N d. 18 hours

3056: A position obtained by applying ONLY your vessel's course and speed to a known position is a __________.

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

3086: Which data must ECDIS be able to record at one-minute intervals?

    Y a. Course made good history
    N b. Estimated time of arrival
    N c. Speed through the water
    N d. Shaft RPM