GPS Jamming

[piratos]

Countries near Russia have often suffered from GPS Jamming. Passenger flights to estonia were returning as landing in Tallin were not considered safe.
Ships, including fast ferries in the Baltic have suffered GPS jamming -- latest jamming was over a period of 11 hours hitting the area around Bornholm (between Sweden and Poland).

I grew up using paper charts, and since I moved from the Baltic to the Med I have bought a set of Paper charts, but are you prepared for the situation when your GPS/Plotter isnt working ?? I have of course folowed the newbuild of JFMs nice SL with plenty of Garmin. Have you also got paper charts in case of no signal...??

 

[westernman]

Yes, I have paper charts.
The loss of GPS for most of what I am doing would not worry me at all as I am mostly coastal hopping.

However, when crossing the 140nm from Rosas Bay to Minorca, it would worry me a bit if visibility was not good enough to ensure a good chance of being able to see the island and not end up sailing straight past it when relying on dead reckoning. Also, I know that my speed indication/log is not very accurate.

 

[noelex]

GPS jamming does not affect the electronic charts.

 

[ImpImp]

It's also been an issue in the Eastern Med and other parts of the ME and is going to be increasingly routine where conflicts of all sorts are occurring.

 

[dunedin]

GPS jamming does not affect the electronic charts.

But many chart plotters through in the towel if no GPS fix, and few make it easy to plot a manual three point fix (cocked hat)

 

[Alicatt]

Funny this topic should come up today, I was installing my SH GX2400 GPS radio this morning and looking at the GPS co-ordinates and comparing them with the Navionics and they did have a small discrepancy between them, so also switched on my handheld VHF which has GPS too and all three had very slightly different co-ordinates on them


They are all less than a meter from each other and using their internal GPS antennas.
Well at least plotting that on a paper chat should give me a cocked hat

 

[Alicatt]

It's also been an issue in the Eastern Med and other parts of the ME and is going to be increasingly routine where conflicts of all sorts are occurring.

There are locations in the UK where I have noted that the GPS signal veers wildly off of what it should be, funny enough they have been quite close to airbases the USAF routinely use, that has/had been going on for more than a decade and after "Selective Availability" had been turned off. It's been about 20 years since I was last past those places.

 

[stranded]

Yes, I have paper charts.
The loss of GPS for most of what I am doing would not worry me at all as I am mostly coastal hopping.

However, when crossing the 140nm from Rosas Bay to Minorca, it would worry me a bit if visibility was not good enough to ensure a good chance of being able to see the island and not end up sailing straight past it when relying on dead reckoning. Also, I know that my speed indication/log is not very accurate.

Little coincidences…

I am watching a YouTube about sailing a Mini 6.5 from Baia Las Roses to Menorca and clicked to this thread immediately after looking where Baia las Roses is on Google maps

Spooky!

 

[noelex]

But many chart plotters through in the towel if no GPS fix, and few make it easy to plot a manual three point fix (cocked hat)

You can still see and use the charts without a GPS fix on the chartplotters and tablets I have owned (Raymarine, Simrad and B&G) , but it is worth checking if some models do not allow this.

It is usually not difficult to put "pencil" marks on an electronic chart. Using traditional techniques such as a three point fix can be done on electronic charts. It is sometimes a little slower and is definitely less satisfying (using paper charts is a pleasure), but it works satisfactorily. It is worth practising this technique as it varies on different hardware. The software will even instantly calculate the bearing of the line.

There is no need to ditch all traditional techniques if you have no paper charts. There is also no need to stop using electronic charts if the GPS fails. The charts themselves are still just as good (and bad ) with or without a GPS fix.

Here is an example of a 3 point fix on an electronic chart.

 

[Refueler]

Funny this topic should come up today, I was installing my SH GX2400 GPS radio this morning and looking at the GPS co-ordinates and comparing them with the Navionics and they did have a small discrepancy between them, so also switched on my handheld VHF which has GPS too and all three had very slightly different co-ordinates on them
View attachment 178512View attachment 178513View attachment 178514View attachment 178515

They are all less than a meter from each other and using their internal GPS antennas.
Well at least plotting that on a paper chat should give me a cocked hat

All well within tolerance of good GPS. If they all said the same - THEN I would be concerned !!

 

[Refueler]

I live and sail from Ventspils - Latvian west coast.

I talk to visitors to the Yacht Harbour and only one has reported any strange GPS .... many others have said they have not noticed any problems ... even though we have had advisorys of interference based on Kaliningrad just down the coast - (Russian Enclave).

I am skeptical of the Tallin Air comment in OP's post - why ? Because there have been no reports on the Radio stations or other media - if such did happen - given the paranoia here - it would be First place breaking news !!

 

[roa312]

The GPS jamming in the Baltics has been traced to two land-based jammers. The first is near St. Petersburg, and the second is in Kaliningrad. Although I'm not an expert on the matter, I understand that it would be more difficult for these stations to affect areas much further away. While GPS jamming can also be caused by satellites, there are methods to prevent it if the issue becomes widespread. Based on my reading, I am skeptical that this is something the average person needs to worry about.

I recommend the video below for anyone interested in the matter and the channel for anyone interested in spaceflight.