Pass Benchmark: 70% (21/30) • Standard: USCG NMC / 46 CFR
USCG Navigation Problems (Set 55)
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Question 1 of 30
You are steering 287°T, and a light is picked up dead ahead at a distance of 19.4 miles at 0419. You change course to pass the light 4 miles off abeam to starboard. If you are making 13 knots, what is your ETA at the position 4 miles off the light?
Browse Questions in Set 55
30 MCQs #1 You are steering 287°T, and a light is picked up dead ahead at a distance of 19.4 miles at 0419. You change course to pass the light 4 miles off abeam to starboard. If you are making 13 knots, what is your ETA at the position 4 miles off the light? #2 You are steering 078°T, and a light is picked up dead ahead at a distance of 15.6 miles at 2316. You change course to pass the light 4.5 miles off abeam to port. If you are making 17 knots, what is your ETA at the position 4.5 miles off the light? #3 The wind at Frying Pan shoals has been south-southwesterly at an average velocity of 30 mph. The predicted set and drift of the rotary current are 232° at 0.8 knot. What current should you expect? #4 The wind in the vicinity of Nantucket Shoals Light has been southerly at an average speed of 23 mph. The predicted set and drift of the rotary current is 225° at 0.8 knot. What current should you expect? #5 The wind at Frying Pan shoals has been west-northwesterly at an average velocity of 40 mph. The predicted set and drift of the rotary current are 323° at 0.6 knot. What current should you expect? #6 The wind at Frying Pan shoals has been north-northeasterly at an average velocity of 30 mph. The predicted set and drift of the rotary current are 355° at 0.8 knot. What current should you expect? #7 The wind at Frying Pan shoals has been northwesterly at an average velocity of 22 mph. The predicted set and drift of the rotary current are 125° at 0.6 knot. What current should you expect? #8 On 5 May in DR position LAT 38°34.5'N, LONG 124°20.7'W, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 07h 59m 10s, and the chronometer error is 01m 10s slow. The sextant altitude (hs) is 67°27.0'. The index error is 1.4' on the arc, and your height of eye is 30 feet. What is the latitude at meridian transit? #9 On 22 February your 1857 ZT DR position is LAT 23°46.0'S, LONG 93°16.5'E. You observe an unidentified star bearing 159°T, at an observed altitude (Ho) of 34°30.0'. The chronometer reads 01h 00m 35s and is 03m 25s fast. What star did you observe? #10 On 10 March in DR position LAT 21°42.0'S, LONG 57°28.0'E, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 08h 28m 17s, and the chronometer error is 00m 00s. The sextant altitude (hs) is 72°08.0'. The index error is 3.4' on the arc, and your height of eye is 52.7 feet. What is the latitude at meridian transit? #11 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? #12 On 16 October evening twilight will occur at 1746 ZT. Your DR position will be LAT 28°43.2'N, LONG 60°29.8'W. Considering their magnitude and location, which of the following are the three best stars to select for a fix at star time? #13 You are turning 90 RPM, with a propeller pitch of 24 feet, and an estimated slip of -3%. What is the speed of advance? #14 On 27 March in DR position LAT 32°31.0'N, LONG 76°25.0'W, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 05h 23m 32s, and the chronometer error is 01m 30s fast. The sextant altitude (hs) is 59°59.0'. The index error is 1.8' off the arc, and your height of eye is 52 feet. What is the latitude at meridian transit? #15 On 11 February your 1832 zone time DR position is LONG 110°52.6'W. At that time you observe Polaris with a sextant altitude (hs) of 26°19.8'. The chronometer time of the sight is 01h 34m 56s, and the chronometer error is 02m 16s fast. The index error is 2.7' off the arc, and the height of eye is 60.2 feet. What is your latitude by Polaris? #16 The speed necessary to reach port at a designated time is 18.7 knots. The propeller pitch is 24'03", and you estimate 3% positive slip. How many revolutions per minute will the shaft have to turn? #17 You are turning 100 RPM, with a propeller pitch of 25 feet, and an estimated slip of -5%. What is the speed of advance? #18 On 23 July your 1700 zone time DR position is LAT 27°29'N, LONG 129°26'W. You are on course 079°T at a speed of 20 knots. Considering their magnitude, azimuth, and altitude, which group includes the three bodies best suited for a fix at star time? #19 On 22 August your 1852 zone time DR position is LONG 155°54.0'E. At that time you observe Polaris with a sextant altitude (hs) of 27°36.9'. The chronometer time of the sight is 08h 54m 06s, and the chronometer error is 02m 20s fast. The index error is 3.6' off the arc, and the height of eye is 61.5 feet. What is your latitude by Polaris? #20 You must average 16.25 knots to reach port at a designated time. Your propeller has a pitch of 21'08", and you estimate 4% negative slip. How many revolutions per minute must you average to arrive on time? #21 On 30 March in DR position LAT 20°26.2'N, LONG 131°17.9'E, you take an ex-meridian observation of the Moon's lower limb at upper transit. The chronometer time of the sight is 10h 36m 02s, and the chronometer error is 02m 06s slow. The sextant altitude (hs) is 48°21.4'. The index error is 2.0' on the arc, and your height of eye is 40 feet. What is the latitude at meridian transit? #22 On 28 February your 1850 zone time DR position is LAT 27°49.0'N, LONG 159°24.0'W. Considering their magnitude, azimuth, and altitude, which group includes the three stars best suited for a fix at star time? #23 On 17 July your 1951 zone time DR position is LAT 24°26.0'N, LONG 51°16.0'W. Considering their magnitude, azimuth, and altitude, which group includes the three bodies best suited for a fix at star time? #24 On 4 September your 1813 zone time DR position is LAT 24°18.0'S, LONG 95°16.0'E. Considering their magnitude, azimuth, and altitude, which group includes the three stars best suited for a fix at star time? #25 On 23 September while taking stars for an evening fix, an unidentified star is observed bearing 261°T at an observed altitude of 61°35'. Your 1836 zone time DR position is LAT 25°18'S, LONG 162°36'E. The chronometer reads 07h 34m 12s, and the chronometer error is 01m 54s slow. Your vessel is steaming on a course of 230°T at a speed of 18 knots. What star did you observe? #26 On 12 April at 0515 ZT, morning stars were observed, and the vessel's position was determined to be LAT 21°05'S, LONG 16°30'W. Your vessel is steaming at 19 knots on a course of 278°T. A sextant observation of the Sun's lower limb is made at 0930 ZT. The chronometer reads 10h 28m 25s, and the sextant altitude (hs) is 40°15.9'. The index error is 2.5' off the arc, and the chronometer error is 2m 15s slow. Your height of eye on the bridge is 57 feet. What is the azimuth (Zn) and intercept (a) based on the assumed position of this sight? #27 On 15 December in DR position LAT 23°24.0'N, LONG 55°36.0'W, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 03h 45m 19s, and the chronometer error is 00m 00s. The sextant altitude (hs) is 43°02.3'. The index error is 2.6' on the arc, and your height of eye is 65.0 feet. What is the latitude at meridian transit? #28 On 30 August in DR position LAT 26°34.0'N, LONG 141°36.0'W, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 09h 15m 26s, and the chronometer error is 00m 00s. The sextant altitude (hs) is 71°41.7'. The index error is 3.2' off the arc, and your height of eye is 49.6 feet. What is the latitude at meridian transit? #29 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? #30 On 22 August in DR position LAT 29°41.8'N, LONG 33°15.5'W, you take an ex-meridian observation of the Moon's upper limb at upper transit. The chronometer time of the sight is 08h 00m 02s, and the chronometer error is 02m 20s slow. The sextant altitude (hs) is 74°32.4'. The index error is 1.5' off the arc, and your height of eye is 48 feet. What is the latitude at meridian transit?
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