What symbol do you use for plotting gps position on chart?

My time in the RN (albeit now rather out of date) we were taught that that a circle plus dot was the fix position, so even if you had a giant cocked hat (my speciality) you put the dot in the position that you considered the 'fix'. You also put your position lines bearings etc on the cahrt so could easily see how the fix was derived. From the time of decca onwards we put a square around the dot to denote the 'electronicness' of the fix.
 
Like a dot in a circle but a dot in a G for GPS
gdot.jpg
 
This is a question that has been nagging me for ages. How refreshing it is to see that we're unanimous on the correct method, then. A GPS derived position should be denoted on the chart by any one of the following (with time recorded beside it, and with or without the letters "GPS"):

1. A dot with a circle around it

2. A dot with a box around it

3. A cross with a circle around it

4. A cross with a box around it

5. A dot with a part circle around it in the shape of a capital G.

Each of the above to be accompanied by the time of the fix. I llike the look of schmoo's (number 5) - it is economical and unambiguous.
 
"I say again...."

[ QUOTE ]
What matters is accuracy, consistency of practice and avoidance of ambiguity.

[/ QUOTE ]
"....out!"

It's one thing to have Raytheon or Garmin do it conveniently for you on a tiny leetl 6" coloured screen; and it's quite another to do it with your own soft and white little hands, on a wet and windy night, with the world and your tum-tum bouncing around like sox in a washing machine.

Kind of sorts the wheat from the chaff....

For those who enjoy such minutiae, the Admiralty Manual of Seamanship ( paperback edition ) will show you how 'The Andrew' likes it, at £80 a throw. Hairy-faced old Tim Bartlett will show you how a sailing journalist likes it, for £12.99, in 'The RYA Navigation Handbook'. And the internationally-revered 'American Practical Navigator' - or 'Bowditch' to the initiates - will show you for free, 'cos the Americans are good like that!

Have a virtual look in here...

[ QUOTE ]
American Practical Navigator – ‘Bowditch’ - Chapter 8 - Piloting – p.133
http://www.marineplanner.com/bowditch/chapt-08.pdf

• Labeling the Fix: The plotter should clearly mark a
visual fix with a circle or an electronic fix with a triangle.
Clearly label the time of each fix. A visual
running fix should be circled, marked “R Fix” and labeled
with the time of the second LOP. Maintain the
chart neat and uncluttered when labeling fixes.


[/ QUOTE ]

....and while you're at it, have a look at the paragraph that follows - which is, for my money, the really important one.




/forums/images/graemlins/smirk.gif
 
[ QUOTE ]
How refreshing it is to see that we're unanimous on the correct method, then. A GPS derived position should be denoted on the chart by any one of the following….
1. A dot with a circle around it.
2. A dot with a box around it.
3. A cross with a circle around it.
4. A cross with a box around it.
5. A dot with a part circle around it in the shape of a capital G.


[/ QUOTE ]

Hence the generic "A quibble of navigators...."


/forums/images/graemlins/laugh.gif
 
OK Bil, we'll be tackling the Little Russel no our trip, in the dark, and I just know you'll love doing it all on paper, as though in fog, with nothing but a sextant and log, and we'll put lace curtains up from the bimini to prevent cheating!

Would you like me to get a liferaft out of the locker now, just in case!!!???

PS I disagree with APN about triangles - they look too much like a lazy three line PL fix that way...
 
I claim a 'lakesailor' here ..................

I hope it will be upheld by those following this thread
 
ahem,

I've been through there on quite a few occasions using traditional nav alone.... because thats all I had..... /forums/images/graemlins/grin.gif however, i'd always have wanted a decent fix first, and wouldn't have done it with a sextant..... (if for no other reason than I don't know how to use one!)

How times move on eh?
 
Didn't you know? A new rule has been added to the Rules of Lakesailoring requiring claimants to post a link to the Rules.
 
[ QUOTE ]
we'll put lace curtains up

[/ QUOTE ]

One of those boats, eh? What colour should I paint my toenails?

Anyway, you've first got to get out of the Needles Channel in one piece - not everyone manages that; then there's The Swinge, on a Spring tide and in characteristic August sea-fog; and the Violet Channel, by St Helier, like the back-side of the moon at low water.... and Les Ecrehous..... and....

Face? Bovvered? Face? Bovvered?

There's nuttin' at all for me to worry about ...... It's your boat!

/forums/images/graemlins/grin.gif

Oh, and BTW, answer your phone and/or your inbox?

/forums/images/graemlins/grin.gif
 
No PM received, though e-mail got here OK. I'll call you tomorrow for details of your cunning plan...
 
if you are old enough its easy to remember - there were pictures of sputnik when it was launched many years ago

[image]http://tbn0.google.com/images?q=tbn:BnGmIDGhkbgDSM[/image]

so put a time on it and '(GPS)' next to the time, and you would get a gold star /forums/images/graemlins/grin.gif
 
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