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.


7: The period at high or low tide during which there is no change in the height of the water is called the __________.


154: Which factor has the greatest effect on the amount of gain required to obtain a fathometer reading?


170: Which of the buoy symbols in illustration D032NG indicates a safe water mark?


295: The difference (measured in degrees) between the GHA of the body and the longitude of the observer is the __________.

    N a. right ascension
    Y b. meridian angle
    N c. SHA of the observer
    N d. zenith distance

302: Which symbol represents a 20-fathom curve?

    Y a. -..-..-..-..-
    N b. - - - - - - - -
    N c. - - . - - . - - . - - .
    N d. - - - - - - - -

313: The Loran-C receiver __________.

    N a. is not affected by interference
    N b. can be used at any distance with accuracy
    Y c. can be affected by interference
    N d. is reliable only from sunrise to sunset

344: A marine sextant has the index arm set at zero and the reflected image of the horizon forms a continuous line with the actual image. When the sextant is rotated about the line of sight the images separate. The sextant has __________.

    N a. error of perpendicularity
    Y b. side error
    N c. prismatic error
    N d. centering error

425: 90° - Ho = __________.

    N a. sextant altitude
    N b. co-latitude
    N c. LHA
    Y d. zenith distance

447: On 27 April 1983, at 1105 DST (ZD +4), what will be the predicted height of tide at Falkner Island, CT?

    Y a. 5.3 feet (1.6 m)
    N b. 5.6 feet (1.7 m)
    N c. 6.2 feet (1.9 m)
    N d. 6.8 feet (2.7 m)

449: You are enroute to assist vessel A. Vessel A is underway at 5 knots on course 063°T, and bears 136°T at 78 miles from you. What is the course to steer at 13 knots to intercept vessel A?

    N a. 340°
    N b. 295°
    N c. 158°
    Y d. 114°

509: A line of position derived by radar range from an identified point on a coast will be a(n) __________.

    N a. straight line
    Y b. arc
    N c. parabola
    N d. line parallel to the coast

623: An indirect radar echo is caused by a reflection of the main lobe of the radar beam off the observer's vessel. Which of the following is NOT a characteristic of indirect echoes?

    N a. Their bearing is almost constant, even when the true bearing of the contact changes appreciably.
    Y b. They always appear on a bearing of 90°From the true bearing of the contact.
    N c. The indirect echoes usually appear in shadow sectors.
    N d. When plotted, their movements are usually abnormal.

652: What agency of the U.S. Government issues charts of U.S. waters and Coast Pilots?

    Y a. National Ocean Service
    N b. National Imagery and Mapping Agency
    N c. U.S. Coast Guard
    N d. U.S. Naval Observatory

675: 15° of latitude is equal to __________.

    N a. 600 miles
    Y b. 900 miles
    N c. 1200 miles
    N d. 1500 miles

725: The First Point of Aries is the position of the Sun on the celestial sphere on or about __________.

    Y a. March 21
    N b. June 21
    N c. September 21
    N d. December 21

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

781: The IALA Buoyage Systems do NOT apply to __________.

    N a. the sides and centerlines of navigable channels
    N b. natural dangers and other obstructions, such as wrecks
    Y c. lighthouses and lightships
    N d. areas in which navigation may be subject to regulation

804: A relative bearing is always measured from __________.

    N a. true north
    N b. magnetic north
    N c. the vessel's beam
    Y d. the vessel's head

914: If the sky was clear, with the exception of a few cumulus clouds, it would indicate __________.

    N a. rain
    N b. hurricane weather
    Y c. fair weather
    N d. fog setting in

955: The line of position determined from a sight with an observed altitude (Ho) of 88°45.0' should be __________.

    N a. reduced to the meridian and plotted as a latitude line
    N b. calculated as a longitude line
    N c. plotted by using an intercept from an assumed position
    Y d. plotted as an arc around the GP of the body

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

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%

1068: A vessel sighting a northern right whale dead ahead should __________.

    N a. maintain course and speed
    Y b. alter course to give a wide clearance
    N c. report the whale's position to the Canadian Coast Guard
    N d. All of the above

1091: The cardinal mark topmark shown in illustration D024NG represents which quadrant? (D024NG )

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

1136: When a warm air mass overtakes and replaces a cold air mass, the contact surface is called a(n) __________.

    Y a. warm front
    N b. cold front
    N c. line squall
    N d. occluded front

1138: On approaching the English Channel on course 080°T, you note the symbol YBY near a charted buoy. You must pass __________.

    N a. northward of the buoy
    N b. southward of the buoy
    N c. eastward of the buoy
    Y d. westward of the buoy

1151: Buoys are marked with reflective material to assist in their detection by searchlight. Which statement is TRUE?

    N a. A safe-water buoy will display red and white vertical stripes of reflective material.
    N b. All reflective material is white because it is the most visible at night.
    N c. A special-purpose mark will display either red or green reflective material to agree with its shape.
    Y d. A preferred-channel buoy displays either red or green reflective material to agree with the top band of color.

1165: Which statement concerning the chartlet is TRUE? (Soundings and heights are in meters) (D010NG )

    N a. Maury lightship is visible for 17 miles.
    Y b. There is a dangerous eddy southeast of Beito Island.
    N c. There is a 12-meter deep west of Beito Island and inside the 5-meter line.
    N d. The bottom to the south-southeast of the lightship is soft coral.

1203: If the compass heading and the magnetic heading are the same then __________.

    N a. the deviation has been offset by the variation
    N b. there is something wrong with the compass
    N c. the compass is being influenced by nearby metals
    Y d. there is no deviation on that heading

1333: If a magnetic compass is not affected by any magnetic field other than the Earth's, which statement is TRUE?

    Y a. Compass error and variation are equal.
    N b. Compass north will be true north.
    N c. Variation will equal deviation.
    N d. There will be no compass error.

1334: The Illustration shows the symbols used on radio facsimile weather charts. The symbol indicated at letter "H" represents __________. (D042NG )

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

1388: If you observe a rapid fall of barometric pressure you should __________.

    N a. call the Coast Guard to verify the change
    N b. know the barometer is not working properly
    N c. contact the NWS or a local radio station
    Y d. prepare for the onset of stormy weather with strong winds

1403: Which statement about the gyrocompass is FALSE?

    Y a. Its accuracy remains the same at all latitudes.
    N b. It seeks the true meridian.
    N c. It can be used near the Earth's magnetic poles.
    N d. If an error exists, it is the same on all headings.

1448: Spring tides occur when the __________.

    N a. Moon is in its first quarter or third quarter phase
    N b. Sun and Moon are in quadrature
    N c. Moon's declination is maximum and opposite to that of the Sun
    Y d. Moon is new or full

1469: The charted channel depth at Eastport, ME, is 28 feet. You are drawing 31.5 feet and wish 2 feet clearance under the keel. What is the earliest time after 1700 (ZD +4) on 6 September 1983 that you can enter the channel?

    N a. 1825
    N b. 1903
    Y c. 1915
    N d. 2003

1493: You are running parallel to the coast and estimate that the current is against you. In plotting a running fix using bearings from the same object on the coast, the greatest safety margin from inshore dangers will result if what speed is used to determine the fix?

    Y a. Minimum speed estimate
    N b. Maximum speed estimate
    N c. Average speed estimate
    N d. A running fix should not be used under these conditions.

1603: A position that is obtained by using two or more intersecting lines of position, taken at nearly the same time, is a(n) __________.

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

1639: Sextant D reads __________. (D043NG )

    N a. 30°47.5'
    N b. 29°47.5'
    Y c. 29°42.5'
    N d. 29°41.6'

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

1683: As it approaches, a typical warm front will bring __________.

    Y a. rising temperatures and falling barometric pressure
    N b. falling temperature and pressure
    N c. falling temperatures and rising pressure
    N d. rising barometric pressure and temperatures

1795: Which weather element cannot be measured accurately while on board a moving vessel?

    N a. Relative humidity
    Y b. Cloud base height
    N c. Temperature
    N d. Atmospheric pressure

1941: IN REGION A of the IALA Buoyage System, when entering from seaward, the starboard side of a channel would be marked by a __________.

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

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)

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.

2361: The range of tide is the __________.

    N a. maximum depth of the water at high tide
    N b. duration of time between high and low tide
    N c. distance the tide moves out from the shore
    Y d. difference between the heights of high and low tide

2363: As shown, the position labeled C was plotted because __________. (D051NG )

    N a. the vessel's speed changed
    N b. the vessel's course changed form due North to due East
    Y c. running fixes are better estimates of true position than dead-reckoning positions
    N d. All of the above are correct

2388: The reference point for determination of GMT is the passage of the mean sun over what line?

    N a. First point of Aries
    N b. Observer's meridian
    N c. 0° longitude
    Y d. 180° longitude

2418: While proceeding downriver, you sight a red triangular-shaped daymark on the left bank. Under the U.S. Aids to Navigation System on the Western Rivers this is a __________.

    N a. special purpose signal
    Y b. passing daymark
    N c. mark with no lateral significance
    N d. crossing daymark

2454: Illustration D037NG represents a moveable dam. If the wickets are down and there are open weirs due to high water, what light(s) will be shown at C if the lock walls and piers are not awash? (D037NG )

    N a. One red light
    Y b. Two red lights
    N c. Three red lights
    N d. One amber light

2469: A tow that is properly aligned to pass through a narrow opening between two bridge piers is "________________".

    N a. on course
    N b. headed fair
    N c. holding on
    Y d. in shape

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.

2695: You are plotting a running fix in an area where there is a determinable current. How should this current be treated in determining the position?

    N a. The drift should be added to the ship's speed.
    N b. The current should be ignored.
    Y c. The course and speed made good should be determined and used to advance the LOP.
    N d. The set should be applied to the second bearing.

2700: In the horizon system of coordinates what is equivalent to the meridian angle of the celestial equator system?

    Y a. Azimuth angle
    N b. Zenith distance
    N c. Colatitude
    N d. Altitude

2777: A sailing chart could have a scale of __________.

    N a. not more than 1:25,000
    N b. 1:35,000
    N c. 1:100,000
    Y d. 1:700,000

2882: While upbound through Memphis, the weather report on TV news indicates that a warm front is stationary over the Kentucky - Missouri - Tennessee areas. What weather conditions should you expect?

    N a. Strong, gusting winds from the NW with thundershowers
    N b. Light winds from the northeast with clear skies
    N c. A "blue norther"
    Y d. Southerly winds with steady rain; fog or overcast

2937: The depth of the water is indicated on a chart as 32 meters. This is equal to __________.

    N a. 11.50 fathoms
    N b. 12.62 fathoms
    Y c. 17.50 fathoms
    N d. 104.99 fathoms

2973: You should plot a dead reckoning position after every __________.

    N a. course change
    N b. speed change
    N c. fix or running fix
    Y d. All of the above

3025: You determine your vessel's position by taking a range and bearing to a buoy. Your position will be plotted as a(n) __________.

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

3084: An ECDIS is required to display which information?

    Y a. Soundings
    N b. Waypoints
    N c. Meteorological data
    N d. Radar targets

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