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.


15: The Vicksburg Gage reads 31.9 feet. The high point on your towboat is 43 feet above the water. What is the vertical clearance as you pass under the Vicksburg Highway 80 Bridge?


38: What are the color and shape of Anconia Pt. Light at mile 528.6 AHP?


256: At 0209, your position is LAT 41°01.8'N, LONG 72°40.8'W. What course should you steer per standard magnetic compass to make good 278° magnetic? (assume no set and drift)


327: At 0315, you obtain the following bearings:

Wolf Trap Light bearing 091° true
Old Plantation Flats Light bearing 179° true

What is the true course from this position to the entrance of York Spit Channel?

    N a. 217°
    N b. 211°
    Y c. 208°
    N d. 203°

407: You depart LAT 34°22'S, LONG 18°23'E, and steam 3174 miles on course 282°T. What is the longitude of your arrival by Mercator sailing?

    Y a. LONG 40°33.5'W
    N b. LONG 40°19.5'W
    N c. LONG 40°18.2'W
    N d. LONG 40°17.3'W

478: The great circle distance from LAT 38°17'N, LONG 123°16'W to LAT 35°01'N, LONG 142°21'E is 4330 miles, and the initial course is 300.9°T. Determine the latitude of the vertex.

    N a. 46°54.8'N
    N b. 47°24.7'N
    N c. 47°35.2'N
    Y d. 47°40.5'N

617: Your vessel will sail from a position in LAT 8°51.0'N, LONG 81°31.0'W to a position at LAT 33°51.5'S, LONG 151°13.0'E. The distance by great circle is 7,635 miles, and you estimate an average speed of 15.0 knots. What is your estimated zone time of arrival if you depart at 1510 ZT, on 23 July?

    Y a. 1110, 14 August
    N b. 0110, 14 August
    N c. 1110, 13 August
    N d. 1510, 13 August

624: You are on a voyage from San Diego, CA, to New York, NY. The distance from pilot to pilot is 4860 miles. The speed of advance is 15.0 knots. You estimate 18 hours for bunkering at Colon, and 14 hours for the Panama Canal transit. If you take departure at 0836 hours (ZD +7), 4 July, what is your ETA (ZD +4) at New York?

    N a. 0336, 20 July
    N b. 0036, 19 July
    N c. 0336, 19 July
    Y d. 0736, 19 July

642: Where can scheduled broadcast times of river stages be found?

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

737: On 29 July , your 1930 zone time DR position is LONG 164°26.0'E. At that time you observe Polaris with a sextant altitude (hs) of 23°46.8'. The chronometer time of the sight is 08h 32m 18s, and the chronometer error is 02m 26s fast. The index error is 2.7' on the arc, and the height of eye is 56.0 feet. What is your latitude by Polaris?

    N a. 24°01.9'N
    Y b. 24°19.5'N
    N c. 24°31.7'N
    N d. 25°19.6'N

1008: On 27 March , your 0730 zone time position is LAT 28°16'N, LONG 56°37'W. Your vessel is on course 158°T at a speed of 15.0 knots. An observation of the Sun's lower limb is made at 0915 zone time. The chronometer reads 01h 14m 11s, and the chronometer error is 00m 53s slow. The observed altitude (Ho) is 45°10.7'. LAN occurs at 1150 zone time, and a meridian altitude of the Sun's lower limb is made. The observed altitude (Ho) is 65°32.8'. Determine the vessel's 1200 zone time position.

    Y a. LAT 27°08.8'N, LONG 56°04.2'W
    N b. LAT 27°08.8'N, LONG 56°10.3'W
    N c. LAT 27°11.6'N, LONG 56°04.2'W
    N d. LAT 27°11.6'N, LONG 56°10.3'W

1089: At 1830 zone time, on 6 April , your DR position is LAT 26°33.0'N, LONG 64°31.0'W. You are steering course 082°T at a speed of 16.0 knots. You observed 3 celestial bodies. Determine the latitude and longitude of your 1900 running fix. NP-0019

    N a. LAT 26°20.1'N, LONG 64°19.4'W
    N b. LAT 26°23.7'N, LONG 64°29.3'W
    N c. LAT 26°28.4'N, LONG 64°32.1'W
    Y d. LAT 26°32.5'N, LONG 64°27.1'W

1118: What are the dimensions of the Old River Lock on the Lower Old River (mile 304 AHP)?

    Y a. 1190 X 75 feet
    N b. 1185 X 84 feet
    N c. 1190 X 84 feet
    N d. 1185 X 75 feet

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

1426: What is the total length of the trip?

    N a. 910.6 miles
    N b. 901.4 miles
    N c. 900.7 miles
    Y d. 873.7 miles

1622: Which of the following statements concerning the buoys on the Mississippi River is TRUE?

    N a. The position of river buoys can be determined by consulting the latest Light List - Vol. V.
    N b. A preferred channel mark is a lateral mark indicating a channel junction which must always be passed to starboard.
    N c. Buoys should be passed as close as possible.
    Y d. Setting a buoy is the act of placing a buoy on assigned position in the water.

1706: The highest point on your towboat is 53 feet above the water, and the Helena Gage (mile 663 AHP) reads 3.9 feet. What is the vertical clearance when you pass under the B-span of the Helena Highway Bridge in Helena?

    N a. 59.9 feet
    Y b. 62.5 feet
    N c. 64.1 feet
    N d. 65.5 feet

1777: At 2232 ZT, on 14 July , in DR position LAT 33°52'S, LONG 150°03'W you observe an amplitude of Jupiter. The planet is about one Sun's diameter above the visible horizon and bears 268.5°pgc. The variation is 15°E. What is the gyro error?

    Y a. 1.0°E
    N b. 0.5°E
    N c. 0.0°
    N d. 0.5°W

1887: On 8 April , your evening DR position is LAT 22°16.0'N, LONG 157°58.3'W. You observe an unidentified star bearing 271°T at an observed altitude (Ho) of 44°08.2'. The chronometer reads 05h 09m 57s, and is 01m 23s slow. What star did you observe?

    N a. Betelgeuse
    Y b. Aldebaran
    N c. Alnilam
    N d. Bellatrix

1888: On 8 April , your evening DR position is LAT 22°16.0'N, LONG 157°58.3'W. You observe an unidentified star bearing 238°T at an observed altitude (Ho) of 50°02.7'. The chronometer reads 05h 09m 57s, and is 01m 23s slow. What star did you observe?

    N a. Betelgeuse
    N b. Aldebaran
    Y c. Alnilam
    N d. Bellatrix

1912: On 22 February , your 1857 DR position is LAT 23°46.0'S, LONG 93°16.5'E. You observe an unidentified star bearing 108°T at an observed altitude (Ho) of 67°53.9'. The chronometer reads 01h 00m 35s, and is 03m 25s fast. What star did you observe?

    Y a. Adhara
    N b. Miaplacidus
    N c. Avior
    N d. Suhail

2051: On which map would you find Redman Point, Arkansas?

    N a. 23
    Y b. 20
    N c. 17
    N d. 5

2151: On 16 June , 0612 zone time, morning stars were observed. The vessel's position was LAT 27°23.0'S, LONG 56°22.0'W. The vessel is steaming at 16.0 knots on a course of 212°T. A sextant observation of the Sun's lower limb is made at 0850 zone time. The chronometer reads 00h 53m 19s, and the sextant altitude is 22°58.6'. The index error is 2.0' off the arc, and the chronometer error is 02m 43s fast. Your height of eye is 61.0 feet. What is the azimuth (Zn) of this sight using the assumed position?

    Y a. 044.3°
    N b. 052.6°
    N c. 136.1°
    N d. 148.4°

2171: On 8 August , at 0545 ZT, morning stars were observed, and the vessel's position was determined to be LAT 26°16.0'
S, LONG 94°16.0'E. Your vessel is steaming at 20.0 knots on a course of 346°T. A sextant observation of the Sun's lower limb is made at 0905 ZT. The chronometer reads 03h 02m 52s, and the sextant altitude (hs) is 38°07.5'. The index error is 5.2' off the arc, and the chronometer error is 2m 17s slow. Your height of eye on the bridge is 72 feet (22.0 meters). What is the observed altitude (Ho) and azimuth (Zn) of this sight using the assumed position?

    Y a. 38°19.4', 048.4°T
    N b. 38°19.4', 131.6°T
    N c. 38°54.9', 048.4°T
    N d. 38°54.9', 131.6°T

2336: You have steamed 916 miles at 13 knots, and consumed 166 tons of fuel. If you have to steam 1325 miles to complete the voyage, how many tons of fuel will be consumed while steaming at 14 knots?

    N a. 133 tons
    N b. 181 tons
    N c. 207 tons
    Y d. 278 tons

2339: You have steamed 1260 miles at 18 knots, and consumed 205 tons of fuel. If you have to steam 1423 miles to complete the voyage, how many tons of fuel will be consumed while steaming at 16 knots?

    N a. 143 tons
    N b. 183 tons
    Y c. 293 tons
    N d. 333 tons

2532: At 0715, on March 9, you pass Knox Landing GagE C313.8 AHP) and estimate the current will average 3.5 mph for the remainder of the time on the Mississippi River. What is your ETA at the mouth of the Ohio River if you increase speed to turn for 10 mph?

    N a. 0640, 11 March
    N b. 0554, 12 March
    Y c. 0943, 13 March
    N d. 1242, 13 March

2877: Your vessel is steering 263°T at 22 knots. At 0413 a light bears 294°T, and at 0421 the same light bears 312°T. What will be your distance off abeam?

    N a. 3.4 miles
    Y b. 3.7 miles
    N c. 4.3 miles
    N d. 4.9 miles

2891: You are steaming on course 168°T at a speed of 18 knots. At 1426 you sight a buoy bearing 144°T. At 1435 you sight the same buoy bearing 116°T. What is your distance off at the second bearing and predicted distance when abeam?

    Y a. 2.3 miles 2nd bearing, 1.8 miles abeam
    N b. 2.5 miles 2nd bearing, 2.8 miles abeam
    N c. 2.8 miles 2nd bearing, 1.8 miles abeam
    N d. 3.3 miles 2nd bearing, 2.8 miles abeam

2906: You are steaming on a course of 211°T at 17 knots. At 0417 a light bears 184°T, and at 0428 the same light bears 168°T. What is the distance off the light at 0428?

    N a. 3.4 miles
    N b. 4.6 miles
    Y c. 5.1 miles
    N d. 5.6 miles

3056: The propeller on a vessel has a diameter of 18.8 feet and a pitch of 21.4 feet. What would be the slip if the vessel cruised 378 miles in a 24 hour day (observed distance) at an average RPM of 76?

    Y a. +1.9%
    N b. -1.9%
    N c. +4.7%
    N d. -4.7%

3057: The propeller on a vessel has a diameter of 25.3 feet and a pitch of 23.2 feet. What would be the apparent slip if the vessel cruised 515 miles in a 23 hour day (observed distance) at an average RPM of 93?

    N a. -3.6%
    N b. +3.6%
    Y c. -5.2%
    N d. +5.2%

3265: You have steamed 1587 miles at 11.2 knots, and have consumed one-half of your total fuel capacity of 2840 bbls. What is the maximum speed you can steam to complete the remaining 1951 miles?

    N a. 9.1 knots
    N b. 9.9 knots
    Y c. 10.1 knots
    N d. 11.6 knots

3277: While steaming at 12.3 knots, your vessel burns 168 bbls of fuel per day. What will be the rate of fuel consumption if you increase speed to 13.5 knots?

    N a. 192 bbls/day
    N b. 204 bbls/day
    Y c. 222 bbls/day
    N d. 238 bbls/day

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

3301: You have steamed 217 miles and consumed 23.0 tons of fuel. If you maintain the same speed, how many tons of fuel will you consume while steaming 362 miles?

    N a. 33.8 tons
    Y b. 38.4 tons
    N c. 42.6 tons
    N d. 45.7 tons

3623: Your vessel is steering course 166°psc, variation for the area is 8°W, and deviation is 3°W. The wind is from the west-southwest, producing a 2° leeway. What true course are you making good?

    Y a. 153°T
    N b. 157°T
    N c. 175°T
    N d. 179°T

12310: You sight North Dumpling Island Light in line with Latimer Reef Light (LAT 41°18.2'N, LONG 71°56.0'W) bearing 091° per standard magnetic compass. If your vessel was heading 246° per standard magnetic compass at the time, which of the following is TRUE?

    N a. The deviation table is correct.
    Y b. The compass error is 18°W for that heading.
    N c. The deviation is equal to the variation.
    N d. The deviation is equal to but of opposite sign to the variation.

14700: How many nautical miles are between mile 105 and mile 234 on the Columbia River?

    Y a. 112.1
    N b. 119.5
    N c. 129.0
    N d. 148.4

15016: If the visibility is 3 miles, at what range will you lose sight of Chesapeake Light?

    N a. The light has never been visible.
    N b. 6.4 miles
    Y c. 8.3 miles
    N d. 12.1 miles

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

15169: At 2123, your position is LAT 37°20.0'N, LONG 76°03.0'W. What is your distance offshore of Savage Neck?

    Y a. 1.7 miles
    N b. 2.5 miles
    N c. 3.6 miles
    N d. 10.9 miles

15259: At 0830, you obtain the following radar information::

Branford Reef Light bearing 259° true @ 4.35 nm


What is your vessel's position?

    N a. LAT 41°12.1'N, LONG 73°53.8'W
    N b. LAT 40°12.2'N, LONG 73°54.4'W
    N c. LAT 41°12.3'N, LONG 72°53.6'W
    Y d. LAT 41°12.4'N, LONG 72°54.0'W

15364: At 0615, Stratford Point Light bears 292°pgc, Falkner Island Light bears 052°pgc, and Branford Reef Light bears 018°pgc. What was the current since 0530?

    Y a. 083° at 1.2 knots
    N b. 083° at 0.9 knots
    N c. 263° at 1.2 knots
    N d. 263° at 0.9 knots

15407: At 1430, your position is LAT 37°12.8'N, LONG 76°17.7'W. At this time, you come left and steer 045°T. This course will lead you through a channel bordered by yellow buoys. The dashed magenta lines between the buoys mark __________.

    N a. York River Entrance Channel
    N b. New Point Comfort shoal area
    N c. the piloting channel for Mobjack Bay
    Y d. the limits of fish trap areas

15626: What type of daymark will you see as you approach Joe Pierce Light (mile 335.4 AHP)?

    N a. Private aid - no daymark
    N b. Red square
    Y c. Red triangle
    N d. Red diamond

15870: What is the approximate distance from a point three miles south of Stratford Point to Perth Amboy, NJ?

    N a. 53 miles
    N b. 62 miles
    Y c. 73 miles
    N d. 136 miles

15939: From your 1910 position, you set a course of 162°T at a speed of 14 knots. What will serve as a definite warning that you are being set towards Race Rock Light?

    N a. Decreasing bearings to Race Rock Light
    Y b. Decreasing loran readings on loran rate 9960-W
    N c. Increasing soundings
    N d. Decreasing radar ranges to Race Point

15967: At 1925, you take a fix using the following radar ranges:
York Spit Light - 3.4 miles away;
New Point Comfort Spit Light "2" - 2.1 miles away;
York Spit Swash Channel Light "3" - 2.7 miles away. Your longitude is __________.

    Y a. 76°16.6'W
    N b. 76°16.8'W
    N c. 76°17.0'W
    N d. 76°17.2'W

16257: If your engines turn for 6.5 knots, and you encounter a 0.5 knot southerly current after weighing anchor. What is your ETA at point A?

    N a. 0511
    N b. 0501
    Y c. 0450
    N d. 0440

16518: At 0845, Montauk Pt. Light is bearing 205°T at a radar distance of 6.6 miles. What is your speed made good from your 0815 position?

    Y a. 8.2knots
    N b. 9.2 knots
    N c. 10.0 knots
    N d. 10.5 knots

16707: Point Judith Harbor of Refuge __________.

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