GPS Disruption what do you think?

[onesea]

Trying to keep this simple, ignoring on-board equipment failure, which we all have different opinions on back ups. As long as using reasonable equipment:

Do you consider loss of position due to external GPS Failure Satellites configuration, Americans Switching off, solar/ weather interference etc. Significant?

For the records I voted:
Not really it will only be short periods of time and still good to mile or 3 00%

Although it depends I would probably go with "I suppose if I knew there would be total outage I might reconsider" depending on passage as I sail for pleasure not for stress (I get enough of that at work).

 

[Noahsdad]

I'd like to think more of an inconvenience though I know on occasion, for me at least, it could be much more significant.

 

[vyv_cox]

It has happened to me but I am not sure how to vote in your poll. Doesn't seem to be a category for me. We were crossing the Bay of Naples when we realised that the gps was not updating. I turned on the backup handheld, which refused to do anything useful. At the time we did not know whether this was temporary or not. It was not a particular problem in the short term as we knew perfectly well where we were, and of course had the chart on the plotter.

After an hour or so the gps returned to normal condition. We subsequently found that the area is a known 'black hole' possibly due to military activity.

 

[AntarcticPilot]

I'm the orignator of the thread that presumably prompted this one. I voted

"Not really it will only be short periods of time and still good to mile or 3 00%"

It's the closest to what I think. But a) if satellites were damaged - and that isn't impossible - it might NOT be for short periods and b) even if I were corssing oceans I'd want an alternative means of position fixing.

I believe in having alternatives for navigation, and grew up sailing in a time when no-one knew their position to high accuracy unless close to navigational markers.

Worth remembering that up till the 1770s mariners were crossing oceans and travelling round the world without the benefit of anything much better than dead-reckoning!

I do think that the potential for loss of accuracy or even total loss of GPS should make people recognize that it isn't a good idea to rely on a single system.

 

[Wandering Star]

Sheesh you youngsters! Decca was the first electronic position finding system I used and that was definitely not to be trusted! Used a traffic light system to show quality of fix which was usually on orange or red but even on green the prudent sailor kept his position plotted hourly with regular log entries. Compared to Decca (or dead reckoning) GPS is reliable and accurate to a degree us old timers wouldn't have believed possible.

So I voted for the wimps option even though I have GPS on my boat and love it.

Cheers, Brian.

 

[MASH]

"Americans switching it off" is not and has not been a possibility for a great may years now. Too much relies on GPS, it would stop the world dead in its tracks.

Time to move on, I think...

 

[tillergirl]

Sheesh you youngsters! Decca was the first electronic position finding system I used and that was definitely not to be trusted! Used a traffic light system to show quality of fix which was usually on orange or red but even on green the prudent sailor kept his position plotted hourly with regular log entries. Compared to Decca (or dead reckoning) GPS is reliable and accurate to a degree us old timers wouldn't have believed possible.

So I voted for the wimps option even though I have GPS on my boat and love it.

Cheers, Brian.

Hear hear Brian. First few times across the channel, the charter vessel didn't even have Decca and I didn't have Decca until my second boat. Funnily enough people seemed to arrive where they intended and were generally safe and sound. GPS is great and handy and good fun but hardly a go or no go issue.

 

[AntarcticPilot]

"Americans switching it off" is not and has not been a possibility for a great may years now. Too much relies on GPS, it would stop the world dead in its tracks.

Time to move on, I think...

They may not switch it off or globally degrade it (remember Selective Availability, anyone? It's still part of the system - just turned down to zero - it's not "off"). Bill Clinton promised they wouldn't and I'm sure we all trust politicians to keep their predecessors promises, don't we?

But the funding for replacing the aging satellites is not yet identified, and I can see the US deciding it doesn't see why it should foot the bill for something used by the whole world. Not a problem at the moment, but there are plenty of "What if?" questions to ask. Galileo perhaps gives more security - but it very, very nearly didn't get built at all, and is incomplete as yet. The politicians' idea of it being commercially viable was given a big thumbs down by industry and it was only political will and face-saving that kept it going. If the Euro is in as bad a shape as everyone says, how long will Germany and France continue to put funding it at the top of their priorities? Glonass is, if anything, in worse shape than the GPS constellation - and I doubt that Russia can afford to repair it on anything like the scale required.

All these systems are at the mercy of political decisions about their future. If some latter-day equivalent of Senator Proxmire decides it's a vote-catcher to oppose it being available for the ROTW, what gives? A promise made by someone who may be seen as a political opponent is all that keeps it available! Bill Clinton's promises hardly have the weight of Washingon, Lincoln or Roosevelt's

Yes, all of this is speculation, and not even very likely speculation. But anything that depends on a space sector that does not produce a directly visible commercial return is basically a political football. The capital outlay of putting even one satellite up is enormous, and the risks are still quite high. Galileo showed that monetizing the system simply won't work. There are alternatives that are much less costly for use in crowded waters (eLoran, for example).

I am not anti-GPS or anything - that would be silly. It is and I hope will continue to be an absolutely amazing system. But I am a realist about the politics of space infrastructure that does not provide a direct return, even if the indirect returns are incalculable. And I trust politicians about as much as anyone else does!

 

[KellysEye]

We used GPS all the time I can't see a reason not to. The only issue is outside Europe where the charts are wrong, the Venezuelan coast is half a mile out and the out islands are three quarters of a mile out. You can see how some yachts and a cosater believed their GPS because there are two yacht wrecks and one coaster on the east coast of Klein Curacao and one yacht wreck on the east coast of Los Roques in the out islands, all hit at night. Also, speaking of Europe, one NE tip of a Greek island is three quarters of a mile out.

 

[onesea]

It has happened to me but I am not sure how to vote in your poll. Doesn't seem to be a category for me. We were crossing the Bay of Naples when we realised that the gps was not updating. I turned on the backup handheld, which refused to do anything useful. At the time we did not know whether this was temporary or not. It was not a particular problem in the short term as we knew perfectly well where we were, and of course had the chart on the plotter.

After an hour or so the gps returned to normal condition. We subsequently found that the area is a known 'black hole' possibly due to military activity.

The question was meant to be 1-5 between the two extremes. I suppose for you the question should be asked with your experience knowing it was going to happen would you do it again?

I'm the orignator of the thread that presumably prompted this one..

Yup

"Americans switching it off" is not and has not been a possibility for a great may years now. Too much relies on GPS, it would stop the world dead in its tracks.

Time to move on, I think...

So your in the first camp then 100% reliance.... I spend half my life relying on GPS and when it does let you down its a PITA even if it is for a few minutes that most do not notice... The system is more fragile than you think...

Wandering Star - TillerGirl:

To be honest it would be like the office computer going down and having to resort to Calculator Fax and a Type Writer.
None essential work would wait till tomorrow, yeah I could get the essentials done for today. Yet if I did not have to stress I would not bother, we are not set up for such failures anymore... I certainly do not workout DR's or EP's as I should...

 

[Deleted member 36384]

Do I think its significant if GPS loses its position due to external factors - yes I do think it is. The system is so convenient that it is ubiquitous and provides much utility. So to lose position is significant.

 

[Ian_Edwards]

In my minds eye there are two conditions:

1) a planned GPS outrage, that wouldn't worry me that much, I'd just revert to what I did pre GPS/DECCA and I'd sail a lot more conservatively, because the pre GPS navigation methods are a lot less accurate.

2) an unexpected, GPS outrage, that would worry me lot, it would take a while to realise that I'd lost a valuable high accuracy tool, and like many people I don't keep a paper back up like I should, mainly because GPS is so reliable. It would take me a while to re-establish confidence in my position and adjust my strategy. eg in pre GPS days when making a land fall, I'd plan to be on the up wind or up tide side of my destination, to make it easy to make the final course adjustments after identifying landmarks. Now I just put a waypoint on the destination and go for it. In pre GPS days was also a lot more reticent to sail at night.

In the NW of Scotland we get regular GPS outrages during military exercises, especially around Raasay and Rona, the last one was just over 2 weeks ago, but they are well advertised and highlighted in the Coast Guard VHF safety broadcast and as per my 1) are not a problem.

I do agree that the current GPS system is aging and it isn't clear to me who and how a replacement will be made available. However, GPS is such an integral part of every day life now, the with GPS in virtually every mobile phone, that I think it unlikely that the politicians will fail to come up with a solution, but it'll probably be late and technically sub-optimum.

 

[Ian_Edwards]

In my minds eye there are two conditions:

1) a planned GPS outrage, that wouldn't worry me that much, I'd just revert to what I did pre GPS/DECCA and I'd sail a lot more conservatively, because the pre GPS navigation methods are a lot less accurate.

2) an unexpected, GPS outrage, that would worry me lot, it would take a while to realise that I'd lost a valuable high accuracy tool, and like many people I don't keep a paper back up like I should, mainly because GPS is so reliable. It would take me a while to re-establish confidence in my position and adjust my strategy. eg in pre GPS days when making a land fall, I'd plan to be on the up wind or up tide side of my destination, to make it easy to make the final course adjustments after identifying landmarks. Now I just put a waypoint on the destination and go for it. In pre GPS days was also a lot more reticent to sail at night.

In the NW of Scotland we get regular GPS outrages during military exercises, especially around Raasay and Rona, the last one was just over 2 weeks ago, but they are well advertised and highlighted in the Coast Guard VHF safety broadcast and as per my 1) are not a problem.

I do agree that the current GPS system is aging and it isn't clear to me who and how a replacement will be made available. However, GPS is such an integral part of every day life now, the with GPS in virtually every mobile phone, that I think it unlikely that the politicians will fail to come up with a solution, but it'll probably be late and technically sub-optimum.