29° 41' 00". D.R. Latitude 41° 30' N, Longitude 33° 38' 45" W. WT 7h 20m 45s A.M. C-W 2h 17m 06s CC + 4m 59s. IE - 30". HE 23 ft. Required Line of Position and most probable position of ship.
| WT | 18d 7h 20m 45s A.M. | ||
| - 12 | |||
| ———————————— | |||
| WT | 17d 19h 20m 45s | ||
| C-W | 2 17 06 | Corr. | + 9' 34" |
| ———————————— | IE | - 30 | |
| CT | 17d 21h 37m 51s | ————— | |
| CC + | 4 59 | + 9' 04" | |
| ———————————— | |||
| G.M.T. | 17d 21h 42m 50s |  | 29° 41' 00" |
| Eq. T. + | 3 47 | + 9 04 | |
| ———————————— | ————— | ||
| G.A.T. | 17d 21h 46m 37s |  | 29° 50' 04" |
| Lo. in T | 2 14 35 (W - ) | ||
| ———————————— | log hav | 9.48368 | |
| L.A.T.(t) | 17d 19h 32m 02s | log cos | 9.87446 |
| Lat. | 41° 30' N | log cos | 9.97473 |
| Dec. | 19° 21' 25" N | ———— | |
| log hav S | 9.33287 | ||
| N s | .21521 | ||
| L ~ D | 22° 08' 35" | N D ± L | .03687 |
| ———— | |||
| Calc. ZD | 60° 16' 30" | N ZD | .25208 |
| - 90° 00 00 | |||
| —————— | TZ found from table to be N 90° E. | ||
| Cal. Alt. | 29° 43' 30" | ||
| | 29° 50' 04" | ||
| —————— | |||
| Alt. Diff | 6' 34" Toward. | ||
| Course. | Dist. | Diff. Lat. | Dep. | Diff. Lo. |
| 90° | 6' 34" | 0 | 6.5 | 8.6 |
| D.R. Lat. | 41° 30' N | D.R. Lo. | 33° 38' 45" W |
| Diff. Lat. | - | Diff. Lo. | 8 36 E |
| —————— | —————— | ||
| Most probable fix | Lat. 41° 30' N | Lo. 33° 30' 09" W |
As azimuth is N 90° E, Line of Position runs due N & S (360°) through Lat. 41° 30' N. Lo. 33° 30' 09" W.
Assign for work in class and for Night Work examples such as the following:
1. July 11th, 1919.
45° 35' 30", Lat. by D. R. 50° 00' N, Lo. 40° 04' W. HE 15 ft. IE - 4'. CT (corrected) 5h. 38m 00s P.M. Required Line of Position by Marc St. Hilaire Method and most probable fix of ship.