USCG Navigation Problems: 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.


44: The highest point on your towboat is 52 feet above the water, and the Helena Gage reads +9.6 feet. What is the vertical clearance when you pass under the A-span of the Helena Highway Bridge?


100: Which of the following statements concerning the buoys on the Mississippi River is TRUE?


148: You are turning for 8.2 mph and estimate the current at 1.5 mph. What is you speed over the ground?


180: On 4 July you observe the lower limb of the Sun at a sextant altitude (hs) of 25°29.8'. The index error is 3.1' off the arc. The height of eye is 48 feet (14.6 meters). What is the observed altitude (Ho)?

    N a. 25°37.1'
    Y b. 25°40.2'
    N c. 25°42.8'
    N d. 25°44.3'

213: From your 1915 position, you come left and set a course for Gardiners Point. At 1930, your position is LAT 41°12.7'N, LONG 71°56.8'W. What type of bottom is charted at this position?

    N a. Blue mud, gritty shells
    N b. Buried mussels, gritty shells
    N c. Bumpy muck with grainy surface
    Y d. Blue mud, gray sand

249: At 0005, on 26 January, your position is LAT 41°11.8'N, LONG 72°20.5'W. From this position, you plot a course to steer to Mattituck Breakwater Light "MI" with an engine speed of 9.0 knots. If there are no set and drift, what course should you steer?

    N a. 225.0°psc
    N b. 230.5°psc
    Y c. 233.0°psc
    N d. 236.0°psc

429: At 0820, you take the following bearings:

Falkner Island Light bearing 052°true
Branford Reef Light bearing 307°true

What are the set and drift since 0730?

    N a. Set 052°T, drift 1.1 knots
    N b. Set 052°T, drift 1.3 knots
    Y c. Set 232°T, drift 1.3 knot
    N d. Set 232°T, drift 1.1 knots

518: Point Judith Harbor of Refuge __________.

    N a. is used mostly by towing vessels
    N b. has a maximum depth of 14 feet at MHW
    Y c. is entered through the East Gap or the West Gap
    N d. is easily accessible in heavy southerly seas

830: On 23 August , in DR position LAT 24°22.0'S, LONG 64°55.3'E, you take an ex-meridian observation of the Moon's upper limb at upper transit. The chronometer time of the sight is 02h 15m 04s, and the chronometer error is 01m 06s fast. The sextant altitude (hs) is 48°03.6'. The index error is 2.0' on the arc, and your height of eye is 60 feet (21.0 meters). What is the latitude at meridian transit?

    Y a. 24°20.5'S
    N b. 24°22.8'S
    N c. 24°24.8'S
    N d. 24°49.5'S

1150: The highest point on your towboat is 48 feet above the water, and the Memphis Gage reads +7.5 feet. What is the vertical clearance when you pass under the Hernando Desoto Bridge in Memphis?

    Y a. 53.2 feet
    N b. 58.1 feet
    N c. 68.2 feet
    N d. 96.3 feet

1215: It is 9 February and you are keeping zone time -6. You are on course 258°T, speed 19 knots. Your 0840 DR position is LAT 26°21.0'S, LONG 78°39.0'E. What is the time of the second estimate of LAN by ship's clocks?

    N a. 12h 05m 21s
    N b. 12h 37m 12s
    N c. 13h 13m 40s
    Y d. 13h 05m 44s

1266: On 1 December , your 1600 ZT DR position is LAT 22°48.0'S, LONG 91°26.0'E. You are on course 327°T at a speed of 16 knots. What will be the zone time of sunset at your vessel?

    N a. 1823
    Y b. 1827
    N c. 1831
    N d. 1847

1271: At 0400 zone time, on 24 June , your DR position is LAT 23°10.0'N, LONG 085°33'W. You are steering 295°T at a speed of 10.0 knots. What is the zone time of sunrise?

    N a. 0452
    Y b. 0458
    N c. 0504
    N d. 0510

1276: Your 0000 zone time position on 13 June is LAT 24°35'N, LONG 142°26'E. Your vessel is on course 245°T, speed is 13.5 knots. What is the zone time of sunrise?

    N a. 0440
    Y b. 0445
    N c. 0503
    N d. 0528

1303: On which map would you find Redman Point, Arkansas?

    Y a. 20
    N b. 38
    N c. 45
    N d. 60

1451: On 11 December , your 1816 ZT DR position is LAT 26°30.0'N, LONG 140°35.0'E. At that time, you observe Venus bearing 230°pgc. The chronometer reads 09h 14m 52s and the chronometer error is 01m 02s slow. The variation is 3.5°E. What is the gyro error?

    N a. 2.2°E
    Y b. 3.3°E
    N c. 3.2°W
    N d. 4.2°W

1480: On 28 November , your vessel's 0712 zone time DR position is LAT 26°54'S, LONG 45°18'W, when you take an azimuth of the Sun. Determine the gyro error using the azimuth information.
Chronometer time: 10h 09m 18s Chronometer error: slow 02m 54s Gyro bearing: 102°

    N a. 1.7°W
    Y b. 0.6°W
    N c. 1.1°E
    N d. 0.8°E

1502: On May 20 , you are keeping ZD +4, and your 2300 (ZD +4) DR position is LAT 42°07'N, LONG 81°02'W. At that time, you observe Polaris bearing 012°psc. The chronometer time of the observation is 03h 02m 23s, and the chronometer is 1m 17s fast. The variation is 9.5°W. What is the deviation of the magnetic compass?

    Y a. 2.7°W
    N b. 12.2°W
    N c. 6.8°E
    N d. 12.2°E

1651: On 23 October , in DR position LAT 21°13.0'N, LONG 152°18.0'E, you observe an amplitude of the Sun. The Sun's center is on the visible horizon and bears 259°psc. The chronometer reads 07h 21m 46s and is 01m 32s slow. Variation in the area is 5°E. What is the deviation of the magnetic compass?

    N a. 0.9°E
    N b. 1.5°W
    Y c. 5.9°W
    N d. 6.5°E

1673: On 17 April , your vessel's position is LAT 21°00'S, LONG 78°30'W, when an amplitude of the Sun is observed. The Sun's center is on the celestial horizon and bears 082.7° per standard magnetic compass. Variation in the area is 2.0°W. The chronometer reads 10h 59m 24s and is 01m 24s fast. What is the deviation of the compass?

    Y a. 2.0°W
    N b. 3.0°W
    N c. 2.5°E
    N d. 3.0°E

2022: On 24 August , your vessel is enroute from Perth, Australia, to Bombay, India. Evening twilight will occur at 1807 zone time, and your vessel's DR position for this time will be LAT 27°17.0'S, LONG 83°17.0'E. Considering their magnitude and location, what are the three stars best suited to observe for a fix at star time?

    N a. Arcturus, Antares, Atria
    Y b. Spica, Altair, Acrux
    N c. Pollux, Canopus, Hamal
    N d. Rasalhague, Spica, Kochab

2106: At 0005, on 26 January, your position is LAT 41°11.8'N,
LONG 72°20.5'W. From this position, you plot a course to steer to a point one half mile north of Mattituck Breakwater Light "MI" with an engine speed of 9.0 knots. If there are no set and drift, what course should you steer?

    N a. 207°psc
    N b. 213°psc
    N c. 220°psc
    Y d. 235°psc

2111: According to the DR track line from your 0100 position, how far off Roanoke Point Shoal Buoy "5" should you be when the buoy is abeam?

    N a. 0.2 mile
    Y b. 0.6 mile
    N c. 1.3 mile
    N d. 1.8 miles

2278: You observe the lower limb of the Sun at a sextant altitude (hs) of 31°31.5' on 6 March . The index error is 2.5' on the arc. The height of eye is 76 feet. What is the observed altitude (Ho)?

    Y a. 31°35.3'
    N b. 31°36.7'
    N c. 31°38.2'
    N d. 31°39.5'

2351: What is the distance in river miles, from the new mouth of the White River to the Petroleum Fuel & Terminal Co. (mile 144.6 AHP)?

    Y a. 454 miles
    N b. 427 miles
    N c. 384 miles
    N d. 370 miles

2700: You are underway on course 163°T at a speed of 15.8 knots.
You sight a buoy bearing 161°T at a radar range of 5.5 miles at 1319. If you change course at 1325, what is the course to steer to leave the buoy abeam to starboard at 1.0 mile?

    Y a. 145°T
    N b. 148°T
    N c. 151°T
    N d. 175°T

2887: Your vessel is steering 283°T at 10 knots. At 0538 a light bears 350°T, and at 0552 the same light bears 002°T. What will be your distance off abeam?

    N a. 9.6 miles
    Y b. 10.3 miles
    N c. 10.7 miles
    N d. 11.3 miles

3279: While steaming at 15.0 knots, your vessel consumes 326 barrels of fuel oil per day. In order to reduce consumption to 178 barrels of fuel oil per day, what is the maximum speed the vessel can turn for?

    N a. 8.1 knots
    N b. 8.5 knots
    N c. 11.1 knots
    Y d. 12.2 knots

3290: While steaming at 15.5 knots, your vessel consumes 333 barrels of fuel oil per day. In order to reduce consumption to 176 barrels of fuel oil per day, what is the maximum speed the vessel can turn for?

    N a. 11.3 knots
    Y b. 12.5 knots
    N c. 13.6 knots
    N d. 14.8 knots

3303: You have steamed 174 miles and consumed 18.0 tons of fuel. If you maintain the same speed, how many tons of fuel will you consume while steaming 416 miles?

    N a. 34.9 tons
    N b. 38.4 tons
    Y c. 43.0 tons
    N d. 46.2 tons

3751: While proceeding up a channel on course 010° per gyro compass, you notice a pair of range lights in alignment with the masts of your vessel when viewed forward. A check of the chart shows the range to be 009°T and the variation to be 15°W. If the ship's course is 026°psc, what is the deviation for the present heading?

    Y a. 2°W
    N b. 2°E
    N c. 1°W
    N d. 1°E

11009: What best describes the structure from which Stratford Point Light is shown?

    N a. Brown conical tower with white horizontal band in center of light on black pier
    N b. Red conical tower on brown cylindrical pier
    N c. White octagonal house on brown cylindrical pier
    Y d. White conical tower, with brown band midway of height

11011: According to the U.S. Coast Pilot, what is the depth of the channel between State Pier No. 1 and the U.S. Navy Submarine Base in New London Harbor?

    N a. 40 feet (12.1 meters)
    N b. 38 feet (11.5 meters)
    Y c. 36 feet (10.9 meters)
    N d. 34 feet (10.3 meters)

11300: At 1256 your GPS position is LAT 36°57.0'N, LONG 75°41.0'W. At 1336 your position is LAT 37°07.5'N, LONG 75°39.1'W. What was the speed made good between the fixes?

    N a. 14.6 knots
    N b. 15.2 knots
    Y c. 16.0 knots
    N d. 18.6 knots

11407: At 1930 your GPS position is LAT 41°00.5'N, LONG 72°49.5'W. At 2018 your position is LAT 41°08.6'N, LONG 72°41.6'W. What was your true course and speed made good?

    N a. 219° at 10.1 knots
    N b. 214° at 12.5 knots
    Y c. 036° at 12.6 knots
    N d. 039° at 11.2 knots

12604: You are on course 082° per standard magnetic compass (psc) when you take the following bearings: New London Ledge Light - 036.5°psc Little Gull Island Light - 157.0°psc Saybrook Break Water Light - 294.5°psc What is your position?

    N a. LAT 41°02.3'N, LONG 72°04.5'W
    N b. LAT 41°09.5'N, LONG 72°07.1'W
    Y c. LAT 41°13.6'N, LONG 72°07.5'W
    N d. LAT 41°14.1'N, LONG 72°12.8'W

13100: Your position is LAT 41°15.2'N, LONG 71°50.1'W at 1347. You are turning for 6.9 knots. What is your ETA at Shagwong Reef Buoy "7SR"?

    Y a. 1506
    N b. 1515
    N c. 1521
    N d. 1527

13104: At 0242 your position is LAT 41°16.8'N, LONG 71°39.9'W. You are turning for 9.3 knots. What is your ETA at the West Gap of Pt. Judith Harbor of Refuge?

    N a. 0319
    N b. 0325
    N c. 0329
    Y d. 0336

13406: You are planning to anchor your vessel at LAT 41°01.1'N, LONG 73°02.8'W. What type of bottom should you expect at this position?

    N a. Gray sand
    N b. Soft mud
    Y c. Gray mud
    N d. Hard sand

14103: You are approaching Bonneville Lock and Dam and desire lockage. Which call sign should you use to contact the lock?

    Y a. WUJ 33
    N b. WUJ 34
    N c. WUJ 41
    N d. WUJ 45

14200: What is the length of the city wharf at The Dalles on the Columbia River?

    N a. 20 feet
    Y b. over 1000 feet
    N c. 800 feet
    N d. 600 feet

15108: Your 1752 position places you __________.

    Y a. less than 0.5 mile westward of York Spit Channel
    N b. less than 0.5 mile eastward of York Spit Channel
    N c. greater than 0.5 mile westward of York Spit Channel
    N d. greater than 0.5 mile eastward of York Spit Channel

15145: At 2357 your position is 41°09.0'N, 71°47.0'W and Montauk Point Light bears 216° true. You change to a course of 293° true and your speed is 14.5 knots. At 0012 Montauk Point Light bears 177° true. Which statement about your 0012 running fix is TRUE?

    N a. You are being set to the north.
    Y b. The fathometer reading is about 14 fathoms.
    N c. You are governed by the Inland Rules of the Road.
    N d. The fathometer trace shows you passed over the 89 foot sounding.

15341: If your fathometer is set on fathoms, what should your fathometer read at 1750?

    Y a. 8.5 fathoms
    N b. 10.2 fathoms
    N c. 14.7 fathoms
    N d. 51.0 fathoms

15444: At 2306, as you pass through Trestle "C", you take a gyro bearing of the trestle when it is in line. The bearing is 049.0°. What is the gyro error?

    Y a. 0°
    N b. 1.5°E
    N c. 1.0°W
    N d. 2.5°W

15612: At 1920, Cape Henry Light bears 225°pgc, and Chesapeake Channel Tunnel North Light bears 288°pgc. If your heading is 268°T, what is the relative bearing of Chesapeake Light?

    N a. 194°
    N b. 205°
    Y c. 213°
    N d. 220°

15642: At 2030 you take the following radar ranges:

Race Rock Light 2.1 miles
Latimer Reef Light 6.4 miles

If you estimate an average current of 080°T at 1.5 knots,
which course will you steer per gyrocompass to leave Endeavor Shoals Gong Buoy bearing 270°T at 1.5 miles?

    N a. 115°
    N b. 118°
    N c. 124°
    Y d. 127°

15658: What course should you steer by the standard magnetic compass in order to maintain a heading of 081°pgc?

    N a. 062°psc
    N b. 080°psc
    N c. 090°psc
    Y d. 095°psc

15662: At 0748, you take the following bearings:

Watch Hill Point Light bearing 026.5°pgc
Race Point Light bearing 275.5°pgc


What is the approximate depth of water under the keel at this position?

    N a. 325 feet (98.5 meters)
    N b. 175 feet (53.0 meters)
    N c. 130 feet (39.4 meters)
    Y d. 112 feet (33.9 meters)

15714: At 1100, your position is LAT 41°11.3'N, LONG 72°28.0'W. You are steering a course of 069°T to leave Black Point one mile off your port beam. It has been reported that the Long Sand Shoal Buoys and Hatchett Reef Buoys are off station. Which of the following will serve as a line marking the hazards and keep your vessel in safe water?

    Y a. Danger bearing to Black Point of not more than 064°T
    N b. Maintaining a 7 nm range off Orient Point
    N c. A bearing to Little Gull Island Light of not less than 090°
    N d. A distance to Saybrook Breakwater Light of not less than 1.3 miles

15721: You are turning for 7.8 mph and estimate the current at 1.0 mph. What is your speed over the ground?

    Y a. 8.8 mph
    N b. 7.9 mph
    N c. 7.8 mph
    N d. 6.8 mph

15756: You are steering 087°pgc and turning for 6.8 knots. At 0600, you take the following bearings:

Little Gull Island Light bearing 085.5°pgc
Bartlett Reef Light bearing 043°pgc

What is your 0600 position?

    Y a. LAT 41°12.1'N, LONG 72°13.8'W
    N b. LAT 41°12.1'N, LONG 72°14.6'W
    N c. LAT 41°12.3'N, LONG 72°14.7'W
    N d. LAT 41°12.5'N, LONG 71°14.9'W

15815: From your 0130 position, you take the following radar ranges:

Mattituck Inlet Light @ 4.6 nm
Falkner Island Light @ 10.75


What is the latitude and longitude of the fix?

    N a. LAT 41°00.8'N, LONG 72°40.8'W
    N b. LAT 41°01.2'N, LONG 72°40.4'W
    N c. LAT 41°01.6'N, LONG 72°40.0'W
    Y d. LAT 41°02.0'N, LONG 72°39.5'W

15841: At 2030 you take the following bearings:

Sand Shoal Inlet South Light - 275°T
Cape Charles Light - 235°T



The set and drift from 2000 to 2030 are __________.

    N a. 088° at 0.7 knot
    N b. 088° at 1.4 knots
    N c. 268° at 0.7 knot
    Y d. 268° at 1.4 knots