National Maritime Center Providing Credentials to Mariners (Sample Examination) Page 1 of 5
Choose the best answer to the following Multiple Choice questions. 1. On 15 October your 0300 zone time DR position is LAT 27 14' S, LONG 99 46' E. You are on course 128 T at a speed of 19 knots. Considering their magnitude, azimuth, and altitude, which group includes the three bodies best suited for a fix at star time? o (A) Mars, Regulus, Canopus o (B) Jupiter, Alphard, Betelgeuse o (C) Achernar, Suhail, Alphard (D) Achernar, Procyon, Aldebaran 2. On 23 July your 2100 ZT position is LAT 36 43.0'N, LONG 16 09.8'W, when you observed an azimuth of Polaris to determine the compass error. Polaris bears 359.0 per gyrocompass. At the time of the observation, the helmsman noted that he was heading 319.0 per gyrocompass and 331.0 per standard compass. Variation is 12.0 W. Which of the following statements is TRUE? o (A) The gyro error is 0.7 E. o (B) The gyro error is 1.7 W. (C) The deviation is 1.7 E. o (D) The compass error is 13.7 W 3. You are on a voyage from Cape May (LAT 39 50'N, LONG 74 45'W) to the English Channel (LAT 49 00'N, LONG 05 00'W). What will NOT prohibit the use of a great circle track from departure to arrival? (Use gnomonic chart WOXZC 5274.) (A) The high latitude in which the vertex lies o (B) Icebergs north of 48 N and west of 49 W o (C) Newfoundland o (D) Islands approximately 50 miles south of Cape Cod 4. In which voyage, between two points, is the rhumb line distance NOT approximately the same as the great circle distance? o o (A) The two points are in low latitudes in the same hemisphere. (B) One point is near the equator, one point is in a high latitude, and both are near the 180th meridian. (C) The two points are in high latitudes in the same hemisphere. o (D) The two points are near the equator, but in different hemispheres. Page 2 of 5
5. On 18 May your 1030 ZT DR position is LAT 20 41'N, LONG 63 32'W. You are on course 106 T, speed 24 knots. Determine your 1200 position using the following observations of the Sun. Zone Time GHA Declination Ho 1204 61 54.6' N 19 37.6' 88 39.7' 1210 63 24.6' N 19 37.7' 88 59.2' (A) LAT 20 32.6'N, LONG 62 57.5'W o (B) LAT 20 30.1'N, LONG 63 01.9'W o (C) LAT 20 27.6'N, LONG 62 52.4'W o (D) LAT 20 25.2'N, LONG 62 56.9'W 6. On 16 July at 2000 zone time, you take a sextant observation of Polaris. Your vessel's DR position is LAT 27 22.0'N, LONG 148 35.0'W, and your sextant reads 26 57.5'. Your chronometer reads 05h 59m 16s, and your chronometer error is 01m 28s slow. Your height of eye is 48 feet, and the index error for your sextant is 1.3' off the arc. What is the latitude of your vessel from your observation of Polaris? o (A) 26 52.1'N o (B) 26 58.8'N (C) 27 36.1'N o (D) 27 43.4'N 7. Determine the distance from LAT 63 54.0'N, LONG 04 52.0'E to LAT 63 54.0'N, LONG 18 24.0'W by parallel sailing. o (A) 608.6 miles o (B) 610.9 miles o (C) 612.3 miles (D) 614.2 miles Page 3 of 5
8. At 2221 your course is 222 pgc at a speed of 11.2 knots, when radar detects a buoy bearing 355 relative, at a range of 5.8 miles. The gyro error is 2 E. If you change course at 2226, what course should you steer to leave the buoy 1.0 mile abeam to port? o (A) 210 pgc (B) 228 pgc o (C) 231 pgc o (D) 206 pgc If choice B is selected set score to 1. 9. On 13 September your 1830 ZT DR position was LAT 23 03'S, LONG 105 16'E, when you observed a faint unidentifiable star through a hole in the clouds. The star bore 148.0 T at a sextant altitude (hs) of 32 24.3'. The chronometer read 11h 24m 39s and is 05m 08s slow. The index error is 1.0' off the arc, and the height of eye is 52 feet. What star did you observe? o (A) Alpha Indi o (B) Beta Aquarii o (C) Beta Gruis (D) Alpha Tucanae 10. On 13 October your 0515 zone time fix gives you a position of LAT 26 53.0'N, LONG 90 05.0'W. Your vessel is on course 068 T, and your speed is 7.8 knots. Local apparent noon (LAN) occurs at 1145 zone time, at which time a meridian altitude of the Sun's lower limb is observed. The observed altitude (Ho) for this sight is 54 51.5'. What is the latitude at 1200 ZT? (A) 27 13.3'N o (B) 27 14.6'N o (C) 27 15.7'N o (D) 27 16.8'N 11. On 10 April, your 1630 ZT DR position is LAT 21 03.0'N, LONG 63 11.0'W. You are on course 324 T at a speed of 22 knots. What will be the zone time of sunset at your vessel? o (A) 1805 o (B) 1814 o (C) 1818 (D) 1833 Page 4 of 5
12. On 12 July your 0800 ZT DR position is LAT 24 15.0'N, LONG 132 30.0'W. Your vessel is on course 045 T at a speed of 15.0 knots. What is the ZT of local apparent noon (LAN)? o (A) 1146 o (B) 1148 (C) 1152 o (D) 1159 13. You observe the lower limb of the Sun at a sextant altitude (hs) of 37 47.2' on 11 October. The index error is 3.0' off the arc. The height of eye is 63 feet (19.2 meters). What is the observed altitude (Ho)? o (A) 37 25.2' o (B) 37 42.5' o (C) 37 51.5' (D) 37 57.5' 14. On 20 November your 1030 ZT DR position is LAT 27 16.0' N, LONG 157 18.6' E. You are on course 060 T at a speed of 20 knots. You observed 3 celestial bodies. Determine the latitude and longitude of your 1200 running fix. Body Zone Time GHA Observed Altitude Declination Moon 1030 259 24.4' 34 01.5' N 9 47.3' Sun 1116 202 30.5' 43 00.0' S 19 38.0' Venus 1200 162 57.7' 24 26.9' S 26 02.4' o (A) LAT 27 16.8'N, LONG 157 30.5'E o (B) LAT 27 22.6'N, LONG 157 37.8'E (C) LAT 27 29.7'N, LONG 157 43.0'E o (D) LAT 27 33.4'N, LONG 157 48.2'E 15. The great circle distance from LAT 35 08.0'S, LONG 19 26.0'E to LAT 33 16.0'S, LONG 115 36.0'E is 4559 miles and the initial course is 121 T. Determine the longitude of the vertex. o (A) 72 18.3'E o (B) 69 19.1'E (C) 65 45.9'E o (D) 26 50.9'E Page 5 of 5