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.


13: Most modern Loran-C receivers, when not tracking properly, have a(n) __________.


71: A preferred-channel buoy may be __________.


226: What winds blow towards the equator from the area about 30 north?


267: You are inbound in a channel marked by a range. The range line is 309T. You are steering 306T and have the range in sight as shown. The range continues to open. What action should you take? (D047NG )

    N a. Alter course to the right to 309T or more to bring the range in line.
    Y b. Alter course to the left until the range closes, then steer to the left of 306T.
    N c. Alter course to the left to close the range, then alter course to 309T.
    N d. Maintain course as it is normal for the range to open as you get close.

386: Your vessel is on course 180T speed 22 knots. The apparent wind is from 70 off the port bow, speed 20 knots. The true direction and speed of the wind are __________.

    N a. 45T, 21.0 knots
    Y b. 51T, 24.0 knots
    N c. 58T, 21.2 knots
    N d. 64T, 26.0 knots

441: A yellow buoy may exhibit a(n) __________.

    N a. fixed red light
    Y b. flashing light
    N c. white light
    N d. occulting light

466: In the relatively calm area near the hurricane center, the seas are __________.

    N a. moderate but easily navigated
    N b. calm
    Y c. mountainous and confused
    N d. mountainous but fairly regular as far as direction is concerned

538: Which symbol shown represents a stationary front? (D018NG )

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

560: On 14 April 1981, a back sight is observed of the lower limb of the Sun. The height of eye is 45 feet. The index error is 2.5' on the arc. The sextant altitude (hs) is 11714.6'. What is the observed altitude (Ho)?

    N a. 6301.9'
    N b. 6303.4'
    N c. 6307.4'
    Y d. 6309.9'

565: The letter B as shown represents the __________. (D006NG )

    Y a. geoidal horizon
    N b. celestial horizon
    N c. visible horizon
    N d. sensible horizon

683: A radar contact will remain stationary on a relative motion radar display only when it is __________.

    N a. on the same course as your vessel
    N b. at the same speed as your vessel
    Y c. on the same course and speed as your vessel
    N d. on a reciprocal course at the same speed as your vessel

693: Which general statement concerning radar is FALSE?

    N a. Raising the antenna height increases the radar range.
    Y b. The ability of radar to detect objects is unaffected by weather conditions.
    N c. Radar bearings are less accurate than radar ranges.
    N d. Radar should be checked regularly during clear weather to ensure that it is operating properly.

702: Which publication contains information on navigation regulations, landmarks, channels, anchorages, tides, currents, and clearances of bridges for Chesapeake Bay?

    Y a. Coast Pilot
    N b. Light List
    N c. Sailing Directions
    N d. Pilot Charts

720: Which change in the condition of the seas could indicate the formation of a tropical storm or hurricane several hundred miles from your location?

    Y a. A long swell from an unusual direction
    N b. A lengthy lull in the wind and seas
    N c. Large seas coming from different directions
    N d. A brisk chop from the southeast

744: A hand held instrument used to measure distances between objects and the ship is a __________.

    N a. vernier
    N b. psychrometer
    N c. hygrometer
    Y d. stadimeter

766: Which position includes the effects of wind and current?

    N a. Dead reckoning position
    N b. Leeway position
    N c. Set position
    Y d. Estimated position

771: Under the IALA Buoyage Systems, a spherical buoy will mark the __________.

    Y a. safe water
    N b. port side of the channel
    N c. a hazard to navigation
    N d. the position of an underwater cable

785: An amplitude of the Sun in high latitudes __________.

    N a. is most accurate before sunrise
    N b. is most accurate after sunset
    N c. should only be observed when the Sun's lower limb is above the horizon
    Y d. is most accurate when the Sun's center is observed on the visible horizon

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

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

841: Under the IALA-A Buoyage system, a buoy marking the port hand of the channel when approaching from seaward may NOT have a __________.

    N a. red light
    Y b. conical shape
    N c. group-flashing light
    N d. square topmark

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

923: A magnetic compass card is marked in how many degrees?

    N a. 90
    N b. 180
    Y c. 360
    N d. 400

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

1009: You are preparing a weather report form, WS Form B-80. The dry bulb thermometer reads 34F, and the wet bulb thermometer reads 31F. Using the ships code card, how would you encode the air temperature groups in the report? (D041NG )

    N a. 10340, 2127/
    N b. 10111, 2104/
    Y c. 10011, 2104/
    N d. 10340, 2031/

1027: In the Northern Hemisphere the major ocean currents tend to flow __________.

    Y a. clockwise around the North Atlantic and North Pacific Oceans
    N b. clockwise or counterclockwise depending on whether it is warm or cold current
    N c. counterclockwise except in the Gulf Stream
    N d. counterclockwise around the North Atlantic and North Pacific Oceans

1058: You are preparing a weather report form, WS Form B-80. Your position is LAT 6442'N, LONG 0228'W. How would this be encoded? (D041NG )

    N a. 90647, 90024
    N b. 0647N, 00025
    Y c. 99647, 70025
    N d. 9064N, 9025W

1111: Black double-cone topmarks are the most important feature, by day, of cardinal marks. Which of the four topmarks shown indicates the best navigable water lies to the west of the buoy? (D030NG )

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

1163: The total magnetic effects which cause deviation of a vessel's compass can be broken down into a series of components which are referred to as __________.

    N a. divisional parts
    Y b. coefficients
    N c. fractional parts
    N d. equations

1184: Your position X is at LAT 35S. Which winds are you experiencing? (D009NG )

    Y a. Northeasterly
    N b. Northwesterly
    N c. Southeasterly
    N d. Southwesterly

1190: Which type of cloud is indicated by the number 2? (D039NG )

    N a. Cumulus
    Y b. Cirrostratus
    N c. Stratocumulus
    N d. Altostratus

1211: Red sectors of navigation lights warn mariners of __________.

    N a. floating debris
    N b. heavily trafficked areas
    N c. recently sunken vessels
    Y d. shoals or nearby land

1256: A cold front moving in from the northwest can produce __________.

    Y a. thunderstorms, hail, and then rapid clearing
    N b. increasing cloud cover lasting for several days
    N c. lengthy wet weather
    N d. low ceilings with thick cirrus clouds

1263: The compass deviation changes as the vessel changes __________.

    N a. geographical position
    N b. speed
    Y c. heading
    N d. longitude

1377: What is the velocity of the tidal current at the east end of Pollock Rip Channel at 1700 DST (ZD +4) on 23 July 1983?

    N a. 0.6 knot ebbing
    N b. 0.8 knot flooding
    Y c. 1.5 knots flooding
    N d. 1.9 knots flooding

1667: Air masses near the earth's surface __________.

    N a. move from areas of high pressure to areas of low pressure
    N b. are deflected by the earth's rotation in both hemispheres
    N c. are deflected by the "Coriolis effect"
    Y d. All of the above

1688: Which type of front forms when a cold front overtakes and forces a warm front upwards?

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

1730: If you observe the point of cloud convergence shifting to the right and the "bar" of the storm appears to move along the horizon __________.

    Y a. the center of the storm will by-pass you
    N b. the storm will strike you on the starboard side
    N c. you are in the direct path of the storm and should take immediate steps to batten down loose gear
    N d. the storm is starting to break up

1745: When your vessel is on the storm track but behind the storm's center the __________.

    N a. wind direction remains steady
    N b. wind speed decreases
    N c. barometer rises
    Y d. All of the above

1784: If your vessel were proceeding down river (descending), a green square marker with a green reflector border on the right bank would be a __________.

    N a. mile board
    N b. dredging mark
    Y c. passing daymark
    N d. crossing daymark

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

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

1974: Ocean currents are well defined and __________.

    N a. create large waves in the direction of the current
    N b. change direction 360 during a 24 hour period
    Y c. remain fairly constant in direction and velocity throughout the year
    N d. are characterized by a light green color

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

2122: A position that is obtained by using two or more intersecting lines of position taken at nearly the same time, is a(n) __________.

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

2146: What lights would you see on the Illinois water way when any wickets of the dam or bear traps are open, or partially open, which may cause a set in the current conditions in the upper lock approach?

    N a. Green over red
    N b. Red over blue
    Y c. Red over amber (yellow)
    N d. None of the above

2226: Upper limb observations of the Moon are used more frequently than those of the Sun because of the location of the Moon in the sky and the __________.

    N a. lesser distance between the Earth and the Moon
    Y b. phase of the Moon
    N c. rapid change in declination of the Moon
    N d. effects of augmentation and horizontal parallax

2237: A lighted buoy to be left to starboard, when entering a U.S. port from seaward, shall have a __________.

    N a. light characteristic of Morse (A)
    N b. white light
    N c. green light
    Y d. red light

2276: A vessel is heading magnetic east and its magnetic compass indicates a heading of 086. Which action should be taken to remove this error during compass adjustment?

    Y a. If the blue ends of the magnets are aft, and the fore-and-aft tray is at the top, you should add some magnets.
    N b. If the blue ends of the magnets are aft you should lower the fore-and-aft tray.
    N c. If the blue ends of the magnets are aft, and the fore-and-aft tray is at the top, you should reverse the magnets.
    N d. If the blue ends of the magnets are forward, and the fore-and-aft tray is at the bottom, you should add some magnets.

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

2424: Under the IALA-B Buoyage System, when entering from seaward a lateral system buoy to be left to starboard may display which of the topmarks shown? (D046NG )

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

2442: 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 004. You should now adjust the compass until it reads __________.

    N a. 356
    N b. 358
    N c. 000
    Y d. 002

2492: A star that suddenly becomes several magnitudes brighter and then gradually fades is a __________.

    N a. double star
    N b. variable star
    Y c. nova
    N d. nebula

2572: The dividing meridian between zone descriptions -4 and -5 is __________.

    N a. 6000'E
    Y b. 6730'E
    N c. 7500'E
    N d. 6000'W

2649: The letter C in illustration D006NG represents the __________. (D006NG )

    N a. geoidal horizon
    Y b. celestial horizon
    N c. visible horizon
    N d. sensible horizon

2662: You must construct a Mercator plotting sheet on a piece of paper measuring 24" by 28". The area includes latitude 37S to 42S and longitude 175E to 179W. Allow a one 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 limitations?

    N a. 3.33 inches
    N b. 3.41 inches
    Y c. 3.67 inches
    N d. 3.82 inches

2716: Under the U.S. Aids to Navigation System on the Western Rivers, passing daymarks on the left descending bank are __________.

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

2800: Where is the pivot point of a towboat with a tow ahead?

    N a. One-third the length of the combined unit forward of the towboat
    Y b. One-third the length of the combined unit back from the head
    N c. At the head of the towboat
    N d. One-half the length of the combined unit

2880: While upbound through Memphis, the weather report on the TV news indicates that a cold front will cross western Kentucky and Tennessee the next morning. What weather should accompany this front?

    N a. Light, southerly winds; high humidity and possibly fog
    N b. Overcast with steady, light rain or drizzle
    Y c. Gusting winds shifting to the northwest with thunderstorms
    N d. Scattered clouds with light to moderate southeasterly winds and possibly fog

2880: While upbound through Memphis, the weather report on the TV news indicates that a cold front will cross western Kentucky and Tennessee the next morning. What weather should accompany this front?

    N a. Light, southerly winds; high humidity and possibly fog
    N b. Overcast with steady, light rain or drizzle
    Y c. Gusting winds shifting to the northwest with thunderstorms
    N d. Scattered clouds with light to moderate southeasterly winds and possibly fog