Lectures in Navigation Part 24

WEEK VIII--NAVIGATION

MONDAY LECTURE

DAY'S WORK

At sea, Nov. 12th, 1918. Departure taken from noon position in Lat.i.tude 39 40' N, Longitude 33 20' 04" W. Log registered at noon 1. Course p.s.c. was 294 until about 3:30 P.M., Deviation 1 W, Variation 24 W, at which time observed alt.i.tude (_) 13 55' 10" and bearing by pelorus S 79 W. WT 3h 22m 18s. C-W 2h 13m 20S. CC + 1m 10s. IE 1' 10" off arc. HE 32 ft. Log registered 46.

Course was then changed to 290 p.s.c. until about 6:30 P.M. when observed alt.i.tude Star Polaris 40 15' 40" N. WT 6h 32m 18s. C-W 2h 13m 20s. Same HE, IE, CC. Log registered 90.

s.h.i.+p steamed on same course until 1:30 A.M. when log registered 196. At 1:30 A.M. sighted sub. on port bow. Ordered full speed ahead and made 17 knots per hour until 8 A.M. when observed alt.i.tude (_) 8 40' 00". WT 8h 01m 30s A.M. C-W 2h 13m 20s. Same HE, IE, CC.

s.h.i.+p then steamed a true course of 272 at a rate of 15 knots per hour until noon, at which time observed meridian alt.i.tude (_) 32 35' 40" S.

Same HE, IE, CC. Log registered 362.

Required 1. D. R. position at noon.

2. Position by observation at noon (corrected for Longitude by a factor).

3. Deviation of Compa.s.s at 3:30 P.M.

4. Watch Time of Local Apparent Noon.

TUESDAY LECTURE

DAY'S WORK

At sea, Dec. 10th, 1918. Departure taken from Lat.i.tude 19 50' N, Longitude 20 01' 20" W. Noon position. Log registered 20. Course p.s.c.

N 16 E. Deviation 2 E, Variation 18 W. s.h.i.+p steamed on this course until 8 P.M. when changed course to N 18 E p.s.c. and observed alt.i.tude Star Polaris 22 33' 14" N. WT 8h 09m 10s. C-W 1h 20m 05s. CC 2m 00s fast. IE none. HE 39 ft. Log registered 104. s.h.i.+p then steamed at 14 knots per hour until midnight. At midnight changed course to N 14 E p.s.c. and steamed at 12 knots per hour until 4 A.M. At 4 A.M. slowed down to 9 knots per hour and steamed at that rate until 8:30 A.M. when course p.s.c. was changed to N 17 E and observed alt.i.tude (_) 22 40'

30". WT 8h 34m 16s A.M. C-W 1h 20m 05s. Same IE, HE, CC. Sun bore by compa.s.s S 65 E, Variation 18 W. Continued on this course p.s.c. for two hours, speed 12 knots. Thence steamed a true course of 4 at same speed to noon when observed meridian alt.i.tude (_) 42 36' 50" S. Same IE, HE, CC.

Required 1. D. R. position at noon.

2. Position by observation at noon (corrected for Longitude by a factor).

3. Deviation of Compa.s.s at 8:30 A.M.

4. Log reading at noon.

WEDNESDAY LECTURE

DAY'S WORK

At sea, July 19th, 1918. Departure taken from Lat.i.tude 40 30' N, Longitude 45 00' 10" W. Noon position. Log registered at noon 68.

Steamed until 2:30 P.M. on a course p.s.c. 115. Deviation 1 W.

Variation 25 W. Log registered 125. Changed course to 118 p.s.c. (Same Variation and Deviation) and steamed until about 5 P.M. At about 5 P.M.

observed alt.i.tude (.) 22 40' 20" and bearing by pelorus N 55 W. WT 5h 01m 16s. C-W 3h 00m 02s. IE 2' 20" on arc. CC 3m 32s slow. HE 32 ft. Log registered 168. Course p.s.c. was then changed to 113 until about 8 P.M. when observed meridian alt.i.tude of Star Vega 88 15' 10" S. WT 8h 02m 26s. C-W 3h 00m 02s. Same HE, IE, CC. Log registered 210. Continued on same course p.s.c. until about 2 A.M. when observed alt.i.tude of Star Vega 47 19' 20" West of meridian. WT 2h 04m 24s A.M. C-W 3h 00m 02s.

Same IE, HE, CC. Log registered 299. TZ of Star N 86 W. Continued on same course until 4 A.M. when log registered 329.

At 4 A.M. heavy fog and rain forced s.h.i.+p to slow down to 5 knots per hour until about 9 A.M. when weather cleared and observed alt.i.tude (_) 51 52' 40". WT 9h 03m 18s A.M. C-W 3h 00m 02s. Same HE, IE, CC. Thence s.h.i.+p steamed a true course of 88 at a rate of 13 knots per hour to noon, when log registered 394 and observed meridian alt.i.tude (_) 69 52'

20" S. Same IE, HE, CC.

Required 1. D. R. position at noon.

2. Position by observation at noon (corrected for Longitude by a factor).

3. Deviation of Compa.s.s at 5 P.M.

4. Watch Time of Local Apparent Noon.

THURSDAY LECTURE

DAY'S WORK

At sea, Nov. 25th, 1918. Departure taken at noon from Lat.i.tude 25 05'

N, Longitude 37 10' 40" W. Log registered at noon 32. Course p.s.c. was 119, Deviation 2 E, Variation 19 W until twilight when log registered 110 and observed alt.i.tude Star Polaris 25 30' 40" N. IE 1' 10" off arc.

HE 28 ft. WT 5h 40m 18s. C-W 2h 28m 11s. CC 4m 15s slow. Changed course to SE x E 3/4 E, same Variation and Deviation, and steamed on this course until about 8:30 P.M. when observed alt.i.tude of Star Markab, West of meridian, 59 48' 10". Log registered 157. WT 8h 34m 48s. C-W 2h 28m 11s. Same HE, IE, CC. Steamed on same course until midnight when log registered 210. Changed course to 110 p.s.c. (same Variation and Deviation), and steamed at 12 knots speed until about 8 A.M. when observed alt.i.tude (_) 23 05' 10" and bearing by compa.s.s S 33 E.

Variation 19 W. WT 8h 04m 10s, A.M. C-W 2h 28m 11s. Same HE, IE, CC.

Continued on same course p.s.c. at a speed of 15 knots per hour until noon when observed meridian alt.i.tude (_) 44" 30' 50" S. Same IE, HE, CC.

Log registered 366.

Required 1. D. R. position at noon.

2. Position by observation at noon (corrected for Longitude by a factor).

3. Deviation of compa.s.s at 8:04 A.M.

4. Watch Time of Local Apparent Noon.