Chris_E
regular
Reged: 13/11/2003
Posts: 4702
Loc: Lymington
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Mine resorts to DL (= Dead Lost!)
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It ain't necessarily so.
Botton Village
Citizens Advice Bureau
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Morgana
regular
Reged: 28/08/2003
Posts: 12654
Loc: East Coast
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hee hee... my preferred navigation technique!
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Bored?.... why not read my blog .... its the developing story of the trials and tribulations of boat ownership!
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whipper_snapper
regular
Reged: 09/08/2006
Posts: 1515
Loc: Kenya
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Quote:
Does anyone here sail in unfamiliar waters without adequate paper charts and pilot information - i.e. does anyone here sail in unfamiliar waters relying on one or more electronic charting systems with no paper backup (which must, obviously, be fit for navigation or it is pointless carrying it)?
I have done and it made me very uneasy. We had to make an unanticipated stop off in Mayotte. We had a pilot which would have been just about sufficient to get in through the reef, but pretty useless for navigating inside the reef. As it was we relied on Maxsea which did not let us down.
We carried appropriate paper charts for the expected tricky bits, plus the most likely alternatives. But sufficiently detailed paper charts for all possibilities are impossible to afford/find/carry. (We also carry a Garmin handheld with spare AAs and complete blue chart coverage. )
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Chris_E
regular
Reged: 13/11/2003
Posts: 4702
Loc: Lymington
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All joking aside, we carry pilots of the areas we intend to cruise and these, combined with the chartplotter have kept me in good stead for the last 10 years. I have had a couple of gear failures which have meant resorting to traditional techniques, albeit using an electonic palette rather than a bit of paper. We have radar which is a useful tool if entering a new port in the murk or dark.
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It ain't necessarily so.
Botton Village
Citizens Advice Bureau
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Lanber
new user
Reged: 14/05/2008
Posts: 1
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I helped a guy sail his new B31C home from Denmark to Norway.
For navigation he had a handheld GPS (with maps) and no paper maps. I had brought my maps along for the trip and sailed by those. The Garmin GPS was too complicated for me to figure out, besides it got quite confusing to see what was a real danger and what was just a note of some kind of deep underwater obstruction. Add on him having way too few batteries for it so you could only turn it on every 1/2h to see what was going on.
When I went off the boat I lent him my maps, they lasted a bit longer on his journey. After that it turned out he relied on road maps, he said the marine maps were too expensive to buy! The coast he went by is regarded as very dangerous waters, he`s lucky he had an experienced sailor with him or I doubt he would have made it.
On my boat I always have paper maps, 2 chartplotters and 1 handhelp gps without maps
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Lemain
regular
Reged: 31/01/2004
Posts: 5814
Loc: Fiumicino canal (Rome, Italy)
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Quote:
don't take regular fixes, or plot my route on the chart (I let the chartplotter do that for me), so when it fails (and I have had it drop reception just on the approach to waypoints) it can take a little time to find and plot the position unless you are constantly identifying features to take bearings from.
I have a simple trick for that which I use when the CP is working, or you can do it with a GPS. I keep a paper chart on the chart table with a line showing track required, and the destination waypoint on the chart (that is vital for this trick to work). Along the 'Track Required' line, from the waypoint backwards, I mark off, using a pair of compasses, five nm sections. Doesn't take long when you get back into using compasses again  . Every hour, I look at two pieces of data from the plotter (or any GPS will do the same) DTW (Distance To Waypoint) and BTW (Bearing To Waypoint) True. I always use True, I only ever work Mag when I am actually 'talking' to a compass. Every hour I write down in the log DTW and BTW. That is quite sufficient to define your position and much, much, easier for a human to a) visualise and b) write down.
I took crew, a recently qualified YM, to help me down to Portugal a couple of years ago and he didn't approve of this odd way of doing things. He actually asked me if I minded if he kept a 'proper' position log alongside!! I didn't mind in the least, of course, and later on in the passage he remarked that my 'approximate' method was really 'quite accurate'  As any applied mathematician, scientist or engineer will tell you, a polar coordinate system is just as accurate as a cartesian coordinate system provided that you use the appropriate accuracy and resolution when distances become large. i.e. write down 'BTW 082.4' and not 082, if your track is very long. By the 'one in sixty rule', one degree results in one nautical mile over sixty miles.
Hopefully that will solve your problem and make plotting a doddle. It's so easy even I do it
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My daily blog on the current financial crisis is at:- http://davidscompass.blogspot.com No PMs for now ybw1.20.lemain@spamgourmet.com
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jerryat
regular
Reged: 20/03/2004
Posts: 3233
Loc: Nr Plymouth
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Quote:
I don't have any electronic ones !
Me neither!!
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KevB
regular
Reged: 04/07/2001
Posts: 5497
Loc: London
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Aha!! but do you have backup paper charts in case one.... Erm fails?
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Nirvana
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Chris_E
regular
Reged: 13/11/2003
Posts: 4702
Loc: Lymington
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Can I sell you some
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It ain't necessarily so.
Botton Village
Citizens Advice Bureau
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RestlessL
regular
Reged: 06/04/2007
Posts: 375
Loc: Solent
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Thanks for that tip - I had not thought of doing of that way (having been brought up in the pre-gps days). Fortunately I have a good stock of 2B pencils.
John
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