Mark-1
Well-Known Member
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For those that rely on GPS, don't go near Cyprus!
- Thread starter dolabriform
- Start date
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ip485
Well-Known Member
Some very good points in reality. I think everyone should think what they would do if the GPS stopped working for any reason, and yes, it could happen for various reasons I have no doubt.
We do end up inclined to be totally dependent on these aids.
I think things have changed however. GPS receivers are definitely more reliable, and more accurate. The price has also fallen dramatically, and if nothing else, most people can fall back on a basic GPS systems on their mobile or pads which they probably have with them most of the time. The more cuatious can also more easily invest in a cheap backup unit of some sort, and even with some basic marine charts.
boatmike
Well-Known Member
Some good points there including having back up. Being a dinosaur I don't much like integrated systems. I have 2 chartplotters of different makes on board and they don't talk to one another so the chance of them both going out at the same time is reduced. I have hand held VHF in addition to the boat system and my radar is independent of everything else. I would never go seriously offshore without my sextant and sight reduction tables although this is rare for me these days and unnecessary for cross channel passages . Apart from this I regularly check and "swing " the mark 1 magnetic compass each year (surprising how far out it can get if you just leave a mobile phone near it!) and always have up to date paper charts on board for the area in question and admiralty tidal stream atlas to calculate best course to steer and log my position at least every hour. I also have and treasure my binoculars with built in hand bearing compass which allows me to keep up my inshore positional triangulation skills. Its actually good fun to check if positions derived in this way agree with GPS and GPS is a wonderful aid in ensuring the magnetic compass course agrees. All totally OTT these days of course but fun to do and the old adage of "there are old sailors and bold sailors but few old bold sailors" is probably true as I have only been sailing for about 67 years and still afloat! In some ways I miss the days when crossing the channel to Cherbourg meant searching for the RDF null to ensure closing up tide of the breakwater entrance. There was much more satisfaction doing that in a sailboat making 3 knots than belting across at 18 knots under twin diesels which is more like what I do now. But hey ho. Its still fun and I can still enjoy being out there.
ip485
Well-Known Member
It was a little before my time in flying, but I recall a good friend of my Dad, RAF and all that sort of thing, a wonderful gentlemen. Anyway took him flying and he recounted a delivery to the Azores. Your last land fall was of course Lands End, you had some basic met, chart, pen, pencil, stop watch. Off you went. The bad news is that if you didnt find the islands there wasnt enough fuel to get to Portugal or any where else. I dont know whether it was entirely true and whether they had anything much else, but I have no reason to not believe him.
I also recall the very early days - was it Decca, I cant remember. I recall making for the Looe channel. Bl**dy fog came down, and my set firstly stopped giving an accurate position entirely if it stopped working for any reason and for some reason I think you had to do something when you crossed the meridian. Of course it did, stop working that is, but we still found the Looe in the fog and went Round the Island a day or two later. It was a dark night as well, fortunately very little wind.
I also recall the very early days - was it Decca, I cant remember. I recall making for the Looe channel. Bl**dy fog came down, and my set firstly stopped giving an accurate position entirely if it stopped working for any reason and for some reason I think you had to do something when you crossed the meridian. Of course it did, stop working that is, but we still found the Looe in the fog and went Round the Island a day or two later. It was a dark night as well, fortunately very little wind.
Newboy6458
Well-Known Member
If you’re really interested in having a back up plan then back to basics nav log with pre calculated distance vs time based on best guess with forecast tide etc can’t be beaten.
Going back to DR visual navigation in light aircraft trying to get the students to just believe in the basics was hard work.
Flying out of Lee on Solent an excellent remedial nav ex was to navigate to the lighthouse at St Catherine’s point, IoW . Wonderful as being below the cliff it’s invisible until you’re there. Fantastic confidence training in proper old fashioned dead reckoning updated for time and drift. Loved it.
Going back to DR visual navigation in light aircraft trying to get the students to just believe in the basics was hard work.
Flying out of Lee on Solent an excellent remedial nav ex was to navigate to the lighthouse at St Catherine’s point, IoW . Wonderful as being below the cliff it’s invisible until you’re there. Fantastic confidence training in proper old fashioned dead reckoning updated for time and drift. Loved it.
Graham_Wright
Well-Known Member
DR.
Graham_Wright
Well-Known Member
Yes.
