Lemain
regular
Reged: 31/01/2004
Posts: 5334
Loc: Fiumicino canal (Rome, Italy)
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I have an old copy of 'Dayskipper' by Pat Langley-Price. It isn't that brilliant, to be honest, and it seems to make fairly simple parts much more complicated than they actually are but it is all there.
It is important to do lots of worked examples and get the answer EXACTLY correct. OK, at sea, you are not really interested in much less than 2-5 degrees heading but only by doing the examples exactly will you be sure that you got the right method!
Don't know about the charts. I've never had an Admiraly Touchchart. I use a very soft 6B pencil and a soft rubber (that's an eraser for the benefit of our American cousins  ) Artists' putty rubbers are excellent, too, as is a damp J Cloth at times. ISTR that Langley-Price came with a practice chart? I also downloaded a Channel Islands real time simulator which was really useful to get my hand back in from a long time away from the sea and lots of aero nav in the meantime. I just kept bashing away on difficult approaches on the simulator until everything fell into place.
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WindFinder
regular
Reged: 03/03/2008
Posts: 291
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Quote:
the entire GPS system could be turned off at any time.
You feel a clockwork watch is less likely to fail than the entire GPS system? Interesting. Of course you could have a back up quartz watch but then you'd be relying on electronics, wouldn't you.
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I would feel far more comfortable in the hands of a sailor who has (and uses from time to time) a sextant
To be anywhere near accurate you need to use a sextant daily day and night over an extended period of time, not just from time to time. You also need a stable platform. Even then you won't be as accurate as GPS. You also seem to be completely unaware of cloud. Grey stuff, ever noticed it?
Like it or not, non-electronic Nav has no equivalent to GPS. Even Decca was better than conventional Nav and that was pretty [--word removed--].
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I fear that it is an accident waiting to happen.
Far, far less dangerous than trusting an EP or even a celestial Fix over a GPS position!
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People should learn the basics and that includes being completely comfortable with how to lay off a course using pencil, ruler, protractor, dividers/compasses, tide tables and some kind of tidal atlas - and, of course, a paper chart.
You're talking about EPs? People like you who don't remember the days when the Decca was always on the blink, need to understand the limitations of conventional nav. Clockwork is not more reliable than the entire GPS system. Celestial fixes are innacurate and very often simply not possible. No matter how good you were on your precious day skipper course trusting an EP over a GPS position is just a joke.
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WindFinder
regular
Reged: 03/03/2008
Posts: 291
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It is important to do lots of worked examples and get the answer EXACTLY correct.
Thanks, that made my day!
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Morgana
regular
Reged: 28/08/2003
Posts: 12278
Loc: East Coast
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And then repeat in a howling gale under a flickering red light, and trying desperately hard (while holding down the vomit) to not substitute 'plotting a course' for 'colouring in'...... 
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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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Fireball
regular
Reged: 15/11/2004
Posts: 7179
Loc: Chichester
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Quote:
No matter how good you were on your precious day skipper course trusting an EP over a GPS position is just a joke.
Isn't this similar to the LR thread ... it is unlikely to happen and you can have a spare at hand quite easily ... chances are that the GPS network won't let you down ... however it would be sensible to know where you are if it does ...
As for loosing the plotter to start with - you could suffer cable break, or general power failure that you cannot resolve quickly - so the most important thing to establish is "where am i" ... the next is "where am i going? and is it safe to do so?" ...
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Don't be sad boy, people die all the time, just like that, why you could wake up dead tomorrow. - Homer Simpson
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WindFinder
regular
Reged: 03/03/2008
Posts: 291
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And then repeat in a howling gale under a flickering red light, and trying desperately hard (while holding down the vomit) to not substitute 'plotting a course' for 'colouring in'......
LOL.
The key skill with conventional Nav is never to say in advance where you're going. That way you can make a near perfect landfall every time. 
Quite seriously I recall one day aiming for Braye we ended up so far to the East with and East going tide that we just changed our minds and went to Cherbourg! Which would have been ok if we hadn't been racing to Braye.
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WindFinder
regular
Reged: 03/03/2008
Posts: 291
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Isn't this similar to the LR thread
Maybe.
There are serious alternatives to LRs and you can probably manage without.
So all the f***-wits claim they are essential.
There's nothing that comes close to the the GPS for identifying a position out of sight of recognizable land.
So all the f***-wits say you shouldn't use 'em!
Edited by WindFinder (16/05/2008 15:33)
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Fireball
regular
Reged: 15/11/2004
Posts: 7179
Loc: Chichester
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I generally find that I know exactly where I am at any moment .... its where everything else is that I have trouble with!
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Don't be sad boy, people die all the time, just like that, why you could wake up dead tomorrow. - Homer Simpson
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temptress
regular
Reged: 15/08/2002
Posts: 643
Loc: Portsmouth, UK
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If my main battery system fails my GPS as well as my plotter go down.
In that event I have a handheld GPS and paper charts. If I drop the GPS then it is back to DR or sextant.
BTW - I have a 'spare' laptop onboard so I guess I could always rig this up but "paper with writing on" technology is a good fallback.
How much redundany do you need? 
We usually do at least one channel crossing each year with the GPS and plotter off just to remind ourselves how it's done. But then we like navigation and SWMBO is a YM instructor as well...............
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Temptress of Down
Southsea Marina
Portsmouth
Hants
UK
Check out our YotBlog
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temptress
regular
Reged: 15/08/2002
Posts: 643
Loc: Portsmouth, UK
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.....The key skill with conventional Nav is never to say in advance where you're going. That way you can make a near perfect landfall every time. .....
Our Log always says "From X towards Y " at the top and then reords at the end where we ended up. Sometimes it's not Y!
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Temptress of Down
Southsea Marina
Portsmouth
Hants
UK
Check out our YotBlog
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