GPS or no GPS

[Geoffs]

Yesterday, I picked a copy of the All At Sea paper. There was an article on the back page about the Volvo Ocean Race. It said at leaast one skipper had declined to start the race because he reckoned that GPS would switched off when war starts.

Blimey, I hadn't thought of that. He also reckoned everyone would get lost. Surely not. Perhaps we'd better brush off our cocked hats, define our areas of uncertainty etc. Now where did I put that parallel rule?

 

[Guest]

how strange. Wd say the US wd have more problems without gps than mountain goaty types who recognise each rock. Good excuse to cop out tho...

 

[ChrisP]

Total and utter rubbish. If the GPS was switched off how would half the armed forces in the world find their own backsides. More likely to reinstate selective error on the domestic sets but with DGPS this still wont make a lot of difference. So what's the point.You sure the story wasn't started by Kelvin Hughs, who by the way still owe me a chart folio from the SBS.

 

[Geoffs]

Must admit I found it difficult to swallow. Unless it can be maintained for military use, just turned off for civil. But then yer Easyjet flight to Palma would probably end up in Kabul, and BarryD's Virgin train would never find Euston.

 

[BarryD]

Geoff - I'm amazed that Virgin ever find Euston and doubly amazed when they find Milton Keynes.

However I'm a bit aeroplaney on the side and during the training navigation plays a major part. Airspeed, wind etc.. have to get it right as you cannot drop your anchor and wait for later. However in the UK GPS is not accepted as a primary air navigation aid, your either use radio beacons or map read as a private pilot or as a commercial pilot the ground radar stations tell you where to go and monitor your respective position. Therefore theorectically GPS is not to be used - having said that every plane I've flown has had GPS - the only thing you have to watch for is entering the way-point incorrectly (but that is another story)!

I think it is likely that they will degrade (SA) the signel but not switch it off.

I would be worried if a professional yacht master did not keep a chart / cross reference as an alternate navigation device. Besides chart work is fun or at least NMCS Day Skipper book N2 would have me believe.

Barry D.

 

[byron]

Codswallop! This is the time that the system was originally developed for and obviously the very time it will be at its utmost accuracy.

©2001

 

[adrianm]

When Clinton made the decision to turn off the selective errors early, he said that the US military had the ability to deny GPS to closely-defined areas of the word.

So even if they did turn it off I doubt the affected areas will concern us.

 

[Guest]

Sometimes (no - quite often!) one wonders how such rubbish gets circulated. No Volvo skipper declined to start. In war the system is even more consistently maintained with extra personnel and limitless finance.

 

[Guest]

The comment about turning off GPS for selected areas is correct there was an official post from the US military last year on the US coastguard website saying that they were testing this facility. It caused many comments and did in fact work. The military GPS's work on a totally different frequency apparantly to the civilian ones hence the cheapest I've seen a surplus millitary one was £1k, that is how SA had no impact on the military once they have enough military spec sets.

 

[byron]

British miltary use standard hand helds on tanks/transport/soldiers. Evince the unavailability in the Gulf War when every unit was bought up - yea behold even those on shop shelves - selectivity was at that time turned off.

©2001

 

[chippie]

My understanding of selective availability was that the level of accuracy was diminished to around 50 metres versus about 5metres. I imagine that if they have this level of control they probably can dial in whatever level of accuracy they want to transmit. I know of at least one civilian agency that had developed a software package to overcome it, but as this was a few years ago the technology may have advanced somewhat.

 

[duncan]

I think you will find that significantly greater accuracy can be achieved in a number of ways - and at cost!

 

[Piers]

Wot's GPS?

 

[Guest]

Re: GPS

You're kidding? Anyway, satellelites in the sky can be monitored by an elctronic contraption to tell you exactly where you are. Actually, they can show and give the exact location and even pictures of everything and everyone in the world. For example, your boat is at N 50.757 degrees W1.532 degrees, and you are at N51.398deg W1.290 degrees, grey roofed building. Good eh?

 

[MikeBrazier]

Re: GPS

I'd say the roof was more of a bluey grey.

 

[Piers]

Re: GPS

Yes, only kidding - trying to bring a smile to readers' faces amongst a long string of opinions....I've been using GPS for many years, and before that, Inertial Navigation Systems, and before that Loran in conjunction with Astro, which all goes to show (as my children would say) that I'm "yesterday" and past my Best Before date....but I still greatly enjoy my motor boat cruising as a substitute to aviation!

Piers