Arrrrrr me hearties, Navigation help needed.

Submitted: Thursday, Mar 19, 2015 at 14:11
ThreadID: 117122 Views:1733 Replies:3 FollowUps:1
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Here’s one for all the Navigation gurus. While transposing some old exploration journals, a few of the navigational directions are described as “South, half West” or “West, half South”.

Now I've picked the odd compass rose or two, know my cardinals, can calculate my reciprocals and also magnetic declination over time and I’m familiar with the 32 compass points so I’m not confusing these with” NNW by West” or “SW by West” etc. These two terms describe something different and I cannot identify just what bearing each refer to. Is it a salty sea-dog way of South West?

I’ve found many a stirring tale of sea exploration where the ship had its head at “West half south” just before it hit the reef but for the life of me I’ve not been able to identify just what these two terms relate to (and I‘ve checked many a glossary of navigation terminology believe me!)

Can anyone tell me what bearing in degrees that each relate to?

Thanks

Mick
''We knew from the experience of well-known travelers that the
trip would doubtless be attended with much hardship.''
Richard Maurice - 1903

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Reply By: Member -Ted (Vic) - Thursday, Mar 19, 2015 at 14:32

Thursday, Mar 19, 2015 at 14:32
Hi Mick

The West 1/2 South is on of the 128 Quarter points if you have a look at this link and display the Quarter points they should answer your question! (I think).
http://en.wikipedia.org/wiki/Points_of_the_compass

Interesting question , never knew of it before!

cheers
Ted
AnswerID: 551207

Reply By: The Explorer - Thursday, Mar 19, 2015 at 14:35

Thursday, Mar 19, 2015 at 14:35
Hello

Don't have a clue but it is mentioned in the literature that:

"The eight half-winds are the points obtained by bisecting the angles between the principal winds. The half-winds are North-northeast (NNE), East-northeast (ENE), East-southeast (ESE), South-southeast (SSE), South-southwest (SSW), West-southwest (WSW), West-northwest (WNW) and North-northwest (NNW). Notice that the name is constructed simply by combining the names of the principal winds to either side, with the cardinal wind coming first, the ordinal wind second. The eight principal winds and the eight half-winds together yield a 16-wind compass rose, with each compass point at a 22 1/2° angle from the next."

I am therefore guessing "South, half West" and "West, half South" could be in reference to this "half wind" terminology. This could mean that "South, half West" = SSW and "West, half South" = WSW....or something like that?

I could have this wrong (I may be a "half wit" :), maybe someone else has some first hand knowledge.

Cheers
Greg
I sent one final shout after him to stick to the track, to which he replied “All right,” That was the last ever seen of Gibson - E Giles 23 April 1874

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AnswerID: 551208

Follow Up By: The Explorer - Thursday, Mar 19, 2015 at 14:40

Thursday, Mar 19, 2015 at 14:40
oh yeah there they are in the 128 point listing from Teds link..

South, half west = 185° 37' 30" S (degrees), S 6° W (bearing)

West, half South = 264° 22' 30" S (degrees), S 84° W (bearing)

...still hurts my head ..

Cheers
Greg

I sent one final shout after him to stick to the track, to which he replied “All right,” That was the last ever seen of Gibson - E Giles 23 April 1874

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Reply By: Member - ROODOO2 - Thursday, Mar 19, 2015 at 14:44

Thursday, Mar 19, 2015 at 14:44
Ted beat me to Wiki by a whisker , Here is a cut / paste of relevant list .Half- and quarter-points
Compass Rose from "American Practical Navigator" 1916

By at least the middle of the eighteenth century the 32-point system had been further extended with the use of half- and quarter-points to give a total of 128 directions.[9] These fractional points are named by appending, for example 1/4east, 1/2east, or 3/4east to the name of one of the 32 points. Each of the 96 fractional points can be named in two ways, depending of which of the two adjoining whole points is used, for example, N3/4E is equivalent to NbE1/4N. Either form is easily understood but differing conventions as to correct usage developed in different countries and organisations.

The table below shows how each of the 128 directions are named. The first two columns give the number of points and degrees clockwise from north. The third gives the equivalent bearing to the nearest degree from north or south towards east or west. The "CW" column gives the fractional-point bearings increasing in the clockwise direction and "CCW" counter clockwise. The final three columns show three common naming conventions: No "by" avoids the use of "by" with fractional points; "USN" the system used by US Navy;[10] and "RN" the Royal Navy.[11] The colour coding illustrates where each of the three naming systems matches the "CW" and "CCW" columns.

Compass roses very rarely named the fractional points and only showed small, unlabelled markers as a guide for helmsmen.
128 Quarter-Points
Points Degrees Bearing CW CCW No "by" USN RN
0 0° 0' 0" N N N N N N
1/4 2° 48' 45" N 3° E N1/4E NbE3/4N N1/4E N1/4E N1/4E
1/2 5° 37' 30" N 6° E N1/2E NbE1/2N N1/2E N1/2E N1/2E
3/4 8° 26' 15" N 8° E N3/4E NbE1/4N N3/4E N3/4E N3/4E
1 11° 15' 0" N 11° E NbE NbE NbE NbE NbE
11/4 14° 3' 45" N 14° E NbE1/4E NNE3/4N NNE3/4N NbE1/4E NbE1/4E
11/2 16° 52' 30" N 17° E NbE1/2E NNE1/2N NNE1/2N NbE1/2E NbE1/2E
13/4 19° 41' 15" N 20° E NbE3/4E NNE1/4N NNE1/4N NbE3/4E NbE3/4E
2 22° 30' 0" N 23° E NNE NNE NNE NNE NNE
21/4 25° 18' 45" N 25° E NNE1/4E NEbN3/4N NNE1/4E NNE1/4E NNE1/4E
21/2 28° 7' 30" N 28° E NNE1/2E NEbN1/2N NNE1/2E NNE1/2E NNE1/2E
23/4 30° 56' 15" N 31° E NNE3/4E NEbN1/4N NNE3/4E NNE3/4E NNE3/4E
3 33° 45' 0" N 34° E NEbN NEbN NEbN NEbN NEbN
31/4 36° 33' 45" N 37° E NEbN1/4E NE3/4N NE3/4N NE3/4N NE3/4N
31/2 39° 22' 30" N 39° E NEbN1/2E NE1/2N NE1/2N NE1/2N NE1/2N
33/4 42° 11' 15" N 42° E NEbN3/4E NE1/4N NE1/4N NE1/4N NE1/4N
4 45° 0' 0" N 45° E NE NE NE NE NE
41/4 47° 48' 45" N 48° E NE1/4E NEbE3/4N NE1/4E NE1/4E NE1/4E
41/2 50° 37' 30" N 51° E NE1/2E NEbE1/2N NE1/2E NE1/2E NE1/2E
43/4 53° 26' 15" N 53° E NE3/4E NEbE1/4N NE3/4E NE3/4E NE3/4E
5 56° 15' 0" N 56° E NEbE NEbE NEbE NEbE NEbE
51/4 59° 3' 45" N 59° E NEbE1/4E ENE3/4N ENE3/4N NEbE1/4E NEbE1/4E
51/2 61° 52' 30" N 62° E NEbE1/2E ENE1/2N ENE1/2N NEbE1/2E NEbE1/2E
53/4 64° 41' 15" N 65° E NEbE3/4E ENE1/4N ENE1/4N NEbE3/4E NEbE3/4E
6 67° 30' 0" N 68° E ENE ENE ENE ENE ENE
61/4 70° 18' 45" N 70° E ENE1/4E EbN3/4N ENE1/4E ENE1/4E EbN3/4N
61/2 73° 7' 30" N 73° E ENE1/2E EbN1/2N ENE1/2E ENE1/2E EbN1/2N
63/4 75° 56' 15" N 76° E ENE3/4E EbN1/4N ENE3/4E ENE3/4E EbN1/4N
7 78° 45' 0" N 79° E EbN EbN EbN EbN EbN
71/4 81° 33' 45" N 82° E EbN1/4E E3/4N E3/4N E3/4N E3/4N
71/2 84° 22' 30" N 84° E EbN1/2E E1/2N E1/2N E1/2N E1/2N
73/4 87° 11' 15" N 87° E EbN3/4E E1/4N E1/4N E1/4N E1/4N
8 90° 0' 0" E E E E E E
81/4 92° 48' 45" S 87° E E1/4S EbS3/4E E1/4S E1/4S E1/4S
81/2 95° 37' 30" S 84° E E1/2S EbS1/2E E1/2S E1/2S E1/2S
83/4 98° 26' 15" S 82° E E3/4S EbS1/4E E3/4S E3/4S E3/4S
9 101° 15' 0" S 79° E EbS EbS EbS EbS EbS
91/4 104° 3' 45" S 76° E EbS1/4S ESE3/4E ESE3/4E ESE3/4E EbS1/4S
91/2 106° 52' 30" S 73° E EbS1/2S ESE1/2E ESE1/2E ESE1/2E EbS1/2S
93/4 109° 41' 15" S 70° E EbS3/4S ESE1/4E ESE1/4E ESE1/4E EbS3/4S
10 112° 30' 0" S 68° E ESE ESE ESE ESE ESE
101/4 115° 18' 45" S 65° E ESE1/4S SEbE3/4E ESE1/4S SEbE3/4E SEbE3/4E
101/2 118° 7' 30" S 62° E ESE1/2S SEbE1/2E ESE1/2S SEbE1/2E SEbE1/2E
103/4 120° 56' 15" S 59° E ESE3/4S SEbE1/4E ESE3/4S SEbE1/4E SEbE1/4E
11 123° 45' 0" S 56° E SEbE SEbE SEbE SEbE SEbE
111/4 126° 33' 45" S 53° E SEbE1/4S SE3/4E SE3/4E SE3/4E SE3/4E
111/2 129° 22' 30" S 51° E SEbE1/2S SE1/2E SE1/2E SE1/2E SE1/2E
113/4 132° 11' 15" S 48° E SEbE3/4S SE1/4E SE1/4E SE1/4E SE1/4E
12 135° 0' 0" S 45° E SE SE SE SE SE
121/4 137° 48' 45" S 42° E SE1/4S SEbS3/4E SE1/4S SE1/4S SE1/4S
121/2 140° 37' 30" S 39° E SE1/2S SEbS1/2E SE1/2S SE1/2S SE1/2S
123/4 143° 26' 15" S 37° E SE3/4S SEbS1/4E SE3/4S SE3/4S SE3/4S
13 146° 15' 0" S 34° E SEbS SEbS SEbS SEbS SEbS
131/4 149° 3' 45" S 31° E SEbS1/4S SSE3/4E SSE3/4E SSE3/4E SSE3/4E
131/2 151° 52' 30" S 28° E SEbS1/2S SSE1/2E SSE1/2E SSE1/2E SSE1/2E
133/4 154° 41' 15" S 25° E SEbS3/4S SSE1/4E SSE1/4E SSE1/4E SSE1/4E
14 157° 30' 0" S 23° E SSE SSE SSE SSE SSE
141/4 160° 18' 45" S 20° E SSE1/4S SbE3/4E SSE1/4S SbE3/4E SbE3/4E
141/2 163° 7' 30" S 17° E SSE1/2S SbE1/2E SSE1/2S SbE1/2E SbE1/2E
143/4 165° 56' 15" S 14° E SSE3/4S SbE1/4E SSE3/4S SbE1/4E SbE1/4E
15 168° 45' 0" S 11° E SbE SbE SbE SbE SbE
151/4 171° 33' 45" S 8° E SbE1/4S S3/4E S3/4E S3/4E S3/4E
151/2 174° 22' 30" S 6° E SbE1/2S S1/2E S1/2E S1/2E S1/2E
153/4 177° 11' 15" S 3° E SbE3/4S S1/4E S1/4E S1/4E S1/4E
16 180° 0' 0" S S S S S S
161/4 182° 48' 45" S 3° W S1/4W SbW3/4S S1/4W S1/4W S1/4W
161/2 185° 37' 30" S 6° W S1/2W SbW1/2S S1/2W S1/2W S1/2W
163/4 188° 26' 15" S 8° W S3/4W SbW1/4S S3/4W S3/4W S3/4W
17 191° 15' 0" S 11° W SbW SbW SbW SbW SbW
171/4 194° 3' 45" S 14° W SbW1/4W SSW3/4S SSW3/4S SbW1/4W SbW1/4W
171/2 196° 52' 30" S 17° W SbW1/2W SSW1/2S SSW1/2S SbW1/2W SbW1/2W
173/4 199° 41' 15" S 20° W SbW3/4W SSW1/4S SSW1/4S SbW3/4W SbW3/4W
18 202° 30' 0" S 23° W SSW SSW SSW SSW SSW
181/4 205° 18' 45" S 25° W SSW1/4W SWbS3/4S SSW1/4W SSW1/4W SSW1/4W
181/2 208° 7' 30" S 28° W SSW1/2W SWbS1/2S SSW1/2W SSW1/2W SSW1/2W
183/4 210° 56' 15" S 31° W SSW3/4W SWbS1/4S SSW3/4W SSW3/4W SSW3/4W
19 213° 45' 0" S 34° W SWbS SWbS SWbS SWbS SWbS
191/4 216° 33' 45" S 37° W SWbS1/4W SW3/4S SW3/4S SW3/4S SW3/4S
191/2 219° 22' 30" S 39° W SWbS1/2W SW1/2S SW1/2S SW1/2S SW1/2S
193/4 222° 11' 15" S 42° W SWbS3/4W SW1/4S SW1/4S SW1/4S SW1/4S
20 225° 0' 0" S 45° W SW SW SW SW SW
201/4 227° 48' 45" S 48° W SW1/4W SWbW3/4S SW1/4W SW1/4W SW1/4W
201/2 230° 37' 30" S 51° W SW1/2W SWbW1/2S SW1/2W SW1/2W SW1/2W
203/4 233° 26' 15" S 53° W SW3/4W SWbW1/4S SW3/4W SW3/4W SW3/4W
21 236° 15' 0" S 56° W SWbW SWbW SWbW SWbW SWbW
211/4 239° 3' 45" S 59° W SWbW1/4W WSW3/4S WSW3/4S SWbW1/4W SWbW1/4W
211/2 241° 52' 30" S 62° W SWbW1/2W WSW1/2S WSW1/2S SWbW1/2W SWbW1/2W
213/4 244° 41' 15" S 65° W SWbW3/4W WSW1/4S WSW1/4S SWbW3/4W SWbW3/4W
22 247° 30' 0" S 68° W WSW WSW WSW WSW WSW
221/4 250° 18' 45" S 70° W WSW1/4W WbS3/4S WSW1/4W WSW1/4W WbS3/4S
221/2 253° 7' 30" S 73° W WSW1/2W WbS1/2S WSW1/2W WSW1/2W WbS1/2S
223/4 255° 56' 15" S 76° W WSW3/4W WbS1/4S WSW3/4W WSW3/4W WbS1/4S
23 258° 45' 0" S 79° W WbS WbS WbS WbS WbS
231/4 261° 33' 45" S 82° W WbS1/4W W3/4S W3/4S W3/4S W3/4S
231/2 264° 22' 30" S 84° W WbS1/2W W1/2S W1/2S W1/2S W1/2S
233/4 267° 11' 15" S 87° W WbS3/4W W1/4S W1/4S W1/4S W1/4S
24 270° 0' 0" W W W W W W
241/4 272° 48' 45" N 87° W W1/4N WbN3/4W W1/4N W1/4N W1/4N
241/2 275° 37' 30" N 84° W W1/2N WbN1/2W W1/2N W1/2N W1/2N
243/4 278° 26' 15" N 82° W W3/4N WbN1/4W W3/4N W3/4N W3/4N
25 281° 15' 0" N 79° W WbN WbN WbN WbN WbN
251/4 284° 3' 45" N 76° W WbN1/4N WNW3/4W WNW3/4W WNW3/4W WbN1/4N
251/2 286° 52' 30" N 73° W WbN1/2N WNW1/2W WNW1/2W WNW1/2W WbN1/2N
253/4 289° 41' 15" N 70° W WbN3/4N WNW1/4W WNW1/4W WNW1/4W WbN3/4N
26 292° 30' 0" N 68° W WNW WNW WNW WNW WNW
261/4 295° 18' 45" N 65° W WNW1/4N NWbW3/4W WNW1/4N NWbW3/4W NWbW3/4W
261/2 298° 7' 30" N 62° W WNW1/2N NWbW1/2W WNW1/2N NWbW1/2W NWbW1/2W
263/4 300° 56' 15" N 59° W WNW3/4N NWbW1/4W WNW3/4N NWbW1/4W NWbW1/4W
27 303° 45' 0" N 56° W NWbW NWbW NWbW NWbW NWbW
271/4 306° 33' 45" N 53° W NWbW1/4N NW3/4W NW3/4W NW3/4W NW3/4W
271/2 309° 22' 30" N 51° W NWbW1/2N NW1/2W NW1/2W NW1/2W NW1/2W
273/4 312° 11' 15" N 48° W NWbW3/4N NW1/4W NW1/4W NW1/4W NW1/4W
28 315° 0' 0" N 45° W NW NW NW NW NW
281/4 317° 48' 45" N 42° W NW1/4N NWbN3/4W NW1/4N NW1/4N NW1/4N
281/2 320° 37' 30" N 39° W NW1/2N NWbN1/2W NW1/2N NW1/2N NW1/2N
283/4 323° 26' 15" N 37° W NW3/4N NWbN1/4W NW3/4N NW3/4N NW3/4N
29 326° 15' 0" N 34° W NWbN NWbN NWbN NWbN NWbN
291/4 329° 3' 45" N 31° W NWbN1/4N NNW3/4W NNW3/4W NNW3/4W NNW3/4W
291/2 331° 52' 30" N 28° W NWbN1/2N NNW1/2W NNW1/2W NNW1/2W NNW1/2W
293/4 334° 41' 15" N 25° W NWbN3/4N NNW1/4W NNW1/4W NNW1/4W NNW1/4W
30 337° 30' 0" N 23° W NNW NNW NNW NNW NNW
301/4 340° 18' 45" N 20° W NNW1/4N NbW3/4W NNW1/4N NbW3/4W NbW3/4W
301/2 343° 7' 30" N 17° W NNW1/2N NbW1/2W NNW1/2N NbW1/2W NbW1/2W
303/4 345° 56' 15" N 14° W NNW3/4N NbW1/4W NNW3/4N NbW1/4W NbW1/4W
31 348° 45' 0" N 11° W NbW NbW NbW NbW NbW
311/4 351° 33' 45" N 8° W NbW1/4N N3/4W N3/4W N3/4W N3/4W
311/2 354° 22' 30" N 6° W NbW1/2N N1/2W N1/2W N1/2W N1/2W
313/4 357° 11' 15" N 3° W NbW3/4N N1/4W N1/4W N1/4W N1/4W
32 360° 0' 0" N N N N N N
AnswerID: 551210

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