oilybilge
Well-Known Member
So that's why I went aground on Shotley Spit last summer.
Bloody Russians.
Bloody Russians.
E-Loran
- Thread starter 14K478
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14K478
Well-Known Member
Oh, well… Shotley Spit … a really devious shoal that, in my fifty five years of sailing around and over it, is never where you think it is!
Anyone can go aground on it. In full public view of everyone in the harbour from the crews of container ships on Trinity Terminal to walkers taking a constitutional promenade on the Shotley sea wall to the pilot boat and tug crews and of course everyone afloat for pleasure…and the harbour cam…
Michael Green in “The Art of Coarse Sailing” mentions “being seized by a giant hand…” - Shotley Spit has giant hands!
I have a very distinct memory of being at the helm of the Red Monster while the crew were all occupied in setting the mainsail… when I happened to glance at the echosounder…we were not where half a century’s experience told me we were… we were over the spit … we had inches under the keel, a tide about to turn , and an engine that had lost interest owing to slime in the fuel…
Saying as little as possible, in order not to spread alarm and despondency in the crew, I spun the wheel and said that we would have more room to hoist on the other tack… I got away with it, that time, but this photo from the harbour cam records the event…
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lustyd
Well-Known Member
Yes that would be harder. Extremely rare though and not something to really worry about.
lustyd
Well-Known Member
The point is that if it’s on their territory it cannot be stopped. That is the issue in the Baltic. If it were being done from Finland then the signal would have been found and stopped.
Most reported incidents are planes and yes are in LOS of the equipment. It’s physics.
Some incidents have happened elsewhere, including London. Most have been found and prosecuted.
Regardless, Loran has nothing that improves the situation at all and is a waste of resources and yet another example of taxpayer money being syphoned off to wealthy mates of MPs. GPS jamming is not an issue in the UK and GPS spoofing is a solved problem.
Minerva
Well-Known Member
hmm. I guess I ought to do a paper chart stock take and do some updates.
Mark-1
Well-Known Member
I also thought spoofing was a bit of an odd reason to pick. If you're going to spoof you need to target to a specific vessel to give a believable SOG/COG/Position. Hard to imagine anyone targeting a leisure yacht. So I just can't imagine spoofing troubling a leisure sailor beyond a bit of head scratching before he turns the GNSS off. In busy areas the issue would be widely reported too. Expect a transmission from the CG.
Jamming's even more straightforward to spot. Your GNSS just stops working in a very obvious way.
If you wanted to cause havoc then you'd be better off jamming GPS in cities. Few of us carry road atlases these days. Switch off Google maps and many of us would be helpless including most delivery drivers and road atlasses would sell out in 10 minutes, if there are any.. (Count me into that. On a boat it's fairly easy to work out where you are, or at least where you're not, in contrast I'm utterly reliant on Google Maps in the car.)
Of all the applications that require functioning GNSS these days cruising sailing is pretty low down the list. For most of us it's a nice to have. (Athough, having done P'mth to Poole without GNSS a few years back it felt a bit weird not knowing where I was to the metre for the first time since 1994. Had to keep reminding myself that I didn't need to know *exactly* where I was. Soon got used to it again.)
Loran is pretty cool though and never went away in some parts of the world. Great that Britain is getting it. (They should call it Decca though, because that's how we roll.
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st599
Well-Known Member
Having experienced spoofing in central London, it's odd, because sometimes it was believable in terms of location, but the timing was way off.I also thought spoofing was a bit of an odd reason to pick. If you're going to spoof you need to target to a specific vessel to give a believable SOG/COG/Position. Hard to imagine anyone targeting a leisure yacht. So I just can't imagine spoofing troubling a leisure sailor beyond a bit of head scratching before he turns the GNSS off. In busy areas the issue would be widely reported too. Expect a transmission from the CG.
Jamming's even more straightforward to spot. Your GNSS just stops working in a very obvious way.
If you wanted to cause havoc then you'd be better off jamming GPS in cities. Few of us carry road atlases these days. Switch off Google maps and many of us would be helpless including most delivery drivers and road atlasses would sell out in 10 minutes, if there are any.. (Count me into that. On a boat it's fairly easy to work out where you are, or at least where you're not, in contrast I'm utterly reliant on Google Maps in the car.)
Of all the applications that require functioning GNSS these days cruising sailing is pretty low down the list. For most of us it's a nice to have. (Athough, having done P'mth to Poole without GNSS a few years back it felt a bit weird not knowing where I was to the metre for the first time since 1994. Had to keep reminding myself that I didn't need to know *exactly* where I was. Soon got used to it again.)
Loran is pretty cool though and never went away in some parts of the world. Great that Britain is getting it. (They should call it Decca though, because that's how we roll.
lustyd
Well-Known Member
In London it may very well have been an urban canyon issue rather than spoofing. Spoofing is extremely rare in the UK. They look the same to the user. GPS is notoriously bad in any heavily built up area, especially with flat reflective surfaces like buildings. AGPS solves some of this to an extent by using wifi and other signals as a hint to real location.
jamie N
Well-Known Member
So, if only we had a clever new system available to overcome this problem?
lustyd
Well-Known Member
Thank goodness it's impossible to spoof a transmission on a given frequency with modern electronicsSo, if only we had a clever new system available to overcome this problem?
"Skipper, I have Dover at 010 degrees and 230 degrees....and 180 degrees!"
14K478
Well-Known Member
I have a Homer / Heron, which obviously isn’t on the boat any more - the last pretext for carrying it - the ability to listen to BBC Radio 4 on 198 - is about to disappear, but it is, in its own way, a beautiful thing, like the sextant and the Walker log.
The start of the rise to greatness of Brookes and Gatehouse is usually dated to the moment when a boat that had sunk in a collision in Cowes Week was raised three weeks later with its Homer / Heron still working!
The start of the rise to greatness of Brookes and Gatehouse is usually dated to the moment when a boat that had sunk in a collision in Cowes Week was raised three weeks later with its Homer / Heron still working!
Marsali_1
Well-Known Member
"Yes that would be harder. Extremely rare though and not something to really worry about."
Until it happens, and then everyone looks around and wonders why it wasn't prepared for. Given the current international political instabilities, I wouldn't be so dismissive of the possibilities of such small scale acts of sabotage. The point is to cause public chaos. Mind you when you are two on a boat at sea its easy to have a world view that extends only to the visible horizon.
Until it happens, and then everyone looks around and wonders why it wasn't prepared for. Given the current international political instabilities, I wouldn't be so dismissive of the possibilities of such small scale acts of sabotage. The point is to cause public chaos. Mind you when you are two on a boat at sea its easy to have a world view that extends only to the visible horizon.
Mark-1
Well-Known Member
I suppose the other issue is will many people in the UK buy another box and another antenna to receive it?
lustyd
Well-Known Member
But this doesn’t prepare for that whatsoever, it has the exact same problems. This is a pure cash grab from the public purse, nothing more.
Dockhead
Well-Known Member
This is false. As a matter of physics, LORAN is vastly more difficult to disrupt than GNSS, to the point of being impractically difficult. Someone went to the trouble of explaining this in detail, and you apparently didn't read it.
Whereas GNSS is trivially easy to disrupt, and is, in fact, being disrupted all over the world every day. You apparently still think that GNSS disruption only occurs "in line of sight from Russia", which is also false.
Dockhead
Well-Known Member
GNSS disruption is not such an existential threat to yachtsmen who have basic navigation skills, so many will not bother, I'm sure. I've experienced GNSS jamming AND spoofing. Once North of Gotland for several hours (hundreds of miles from Russian territory!). It's not a big deal if you can do DR.
When LORAN is restored, I will be one of those who buys the box. I actually own an old LORAN receiver somewhere. It will require a 50cm monopole antenna which can be pushpit mounted -- to transmit you, you need at least a 50m long antenna, and typically a few hundred meters. Here's the gigantic triatic LORAN antenna at Rugby: The Loran ‘C’ Navigation Service | Radiostation Rugby - Connecting you to now.
GNSS disruption is a much bigger problem for aircraft and commercial vessels, especially for aircraft. See: GPSJAM GPS/GNSS Interference Map. And a huge problem for land-based services.
It's expected to get worse and worse as non-state actors now have access to the fairly simple technology involved. One of the biggest threats is expected to be jammer carried in balloons. A 100 watt jammer can cost as little as a few thousand and can be carried by a small weather balloon, and can disrupt a large sea area for days. And may fly at altitudes which make it difficult to shoot down with anything less than a multi-million pound air to air missile.
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14K478
Well-Known Member
I got the distinct impression that the MCA are expecting people who go to sea to fish and people who go to sea for fun to do exactly this, and if the box and the antenna for the GPS go the same way as the RDF set and the Decca receiver then so far so normal.
lustyd
Well-Known Member
I did read it. Lots of waffle about power output but ignored that that power is needed for range. Locally it doesn’t take much power to disrupt.
I said line of sight of Russian territory in the Baltic, which is a documented fact.
lustyd
Well-Known Member
My chart says about 150 to the north side. Not sure I’d call that hundreds.
Dockhead
Well-Known Member
All false. GNSS satellites have 50 to 100 watt transmitters, and they are in MEO at least 20,000km from the Earth's surface. A 100 watt jammer in a £500 weather balloon 20km from the surface can totally blank out GNSS service over a huge sea area.
How many of these events -- occurring in a single day -- are in "line of sight of Russian territory"?
