GPS coverage in the Clyde will be restricted this week

Hermit

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until somebody jams the GNSS (GPS et al) signals - which was where this tread started
.......until someone or something renders the GPS unreliable.

No, not at all. The ECDIS is quite capable of manual visual fixing. Take a bearing, line it up and input it to a fix tote. Fast and very accurate as the time of the bearing line can be to the second.

Yes, it relies on power to keep the ECDIS console running - but they all have uninterruptible power supplies (UPS).

Yes, need power to keep the 2 gyros (actually, intertial navigation systems so as well as heading they give a position output so don't really need GPS anyway) and have UPS. Plus they have a corrected mag compass.

Yes, they also carry sextants, but they are more used for HSA's and VSA as per the Capn's post. (HSA and VSA can also be plotted on ECDIS).

I state a little interest - I did the course shown above in 2006 and now deliver and maintain the Integrated Navigation and Bridge Systems for the Type 45s, Type 26s and Type 31s
 
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CM74

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Haha don't be so shocked - this is on the tug at work so we also have a proper, adjusted magnetic compass with a deviation card...

To clarify, the GPS compass isn't something just giving COG, it gives a true heading based on 3 receivers in a triangle shape that very cleverly calculates our true heading. It's basically an alternative to a Gyrocompass.
The GPS compass feeds the heading input for our radar/arpa though, as well as the AIS. We can run the autopilot from the magnetic compass too but it's prone to doing strange things - I have a feeling that I'll be the one delegated to play with the thing to get it to behave if it does play up!

So we have plenty of contingencies in place (and we use them) but I have questioned the wisdom of it myself before. Ultimately though Lloyds and the MCA are happy with it :)

And yes - the clyde is very well marked, especially the main channels that we use, so it's all a bit academic really. It'll be interesting to see what happens with all the GPS gear
 

Never Grumble

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ECDIS has pretty much rendered Blind Pilotage obsolete. Why work on 2 lines in contact with the land on a radar when, if you use a radar overlay on your chart, you have thousands of point of contact. Parrellel Index lines are still used a check but, also, with a modern integrated navigation system, the radar and the chart work together seamlessly.
Good to know that things have moved on for the better. Having to prove yourself 'blind' capable at Portland by using a chinagraph pencil on a standalone radar display at the back of the bridge was sure to bring you out in a sweat, at least it did me.
 

adwuk

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MarineTraffic says that she was off Norway on Monday, but there are several reports of her at Glen Mallan. Goes to show how effective the GPS interference is :)
 

awol

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MarineTraffic says that she was off Norway on Monday, but there are several reports of her at Glen Mallan. Goes to show how effective the GPS interference is :)
Fake News to confuse the ruskies. The obvious photo-shopping of the QE against the Argyll hills will fool nobody! They even closed all the local roads to make the ruse look even better.
 

SaltIre

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Fake News to confuse the ruskies. The obvious photo-shopping of the QE against the Argyll hills will fool nobody! They even closed all the local roads to make the ruse look even better.
Here's a very cleverly edited clip allegedly from the bridge of @HMSQNLZ with a lovely view of a tanker berthed at Finnart. The fake piper is playing a German melody.
 

Bilgediver

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So does that mean it impacts other satellite constellations that are strictly not "GPS"?
It only affects GPS signals and mainly in the area in which The Lizzie is operting.

Maybe a good reason to splash the cash on Plastimo. Should be a magnetic compass in your grab bag ???? :)
 

Bilgediver

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Don't you realise all this fake news is what our government wants us to promulgate? All the while the QE and PoW are creeping up on them via the North Sea.
AN official Notam was issued regarding this. Hardly fake news and they are frequently issued when the big excersizes are on.

If you see a wee red spot hovering on your deck then jump overboard and swim for your life as what might follow is not effacted. ;)
 

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