GPS coverage in the Clyde will be restricted this week

Bugger! Do you have any more info? Even our compass is GPS so it's not ideal depending on exactly what the problem is...

Saying that, it wouldn't be the only time we've had GPS issues, they seem to be more common when the US Navy are around!
 
I have no idea what the word restricted means but the map shows restricted GPS all the way down the Clyde to almost Troon. It is to protect HMS Queen Elizabeth from missile attack I guess. Airspace is restricted also.
 
mainsail1 said:
I have no idea what the word restricted means but the map shows restricted GPS all the way down the Clyde to almost Troon. It is to protect HMS Queen Elizabeth from missile attack I guess. Airspace is restricted also.
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So does that mean it impacts other satellite constellations that are strictly not "GPS"?
 
mjcoon said:
So does that mean it impacts other satellite constellations that are strictly not "GPS"?
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Interesting question- wasn’t one of the drivers behind both GLONAS and Galileo networks that they would be independent from GPS network and not easily turned off by the yanks?
 
Minerva said:
Interesting question- wasn’t one of the drivers behind both GLONAS and Galileo networks that they would be independent from GPS network and not easily turned off by the yanks?
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Exactly, not to mention China's Beidou. GLONASS (wikipedia.org=GLONASS apparently 2 x Ss), being Russian, would have to be independent! I believe most consumer navigation devices use whichever they can see.

E.g. from an app on my phone: mobiwia.com/gpsstatus
The sky grid (G) shows the GPS satellites above you as the receiver in the phone detects them. GPS satellites (with IDs 1-32) are represented by disks. GLONASS satellites (with IDs r1-r25) are shown as rectangles, BEIDOU satellites (with IDs c1-c33) are shown as crosses (x) while GALILEO sats (with IDs e1-e35) are displayed as plus (+) signs. The size of the symbol depends on the signal strength received from that satellite. The colour shows what data is available for that satellite and how it is currently used by the phone.
  • green: satellite is used while determining the location
  • yellow: all orbital data is available, but the satellite is not used
  • blue: only rough orbital data (almanac) is available
  • grey: orbital data is not available
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Its an interesting intellectual issue . But is it really critical

It will give you opportunity to dust off the paper charts. It might be said that if you cannot navigate without GPS (and even rely on GPS for your compass) then maybe you should advise your guests and crew of your lack of basic navigation skills. Also possibly invest in Stemar's suggestion - or even a cheap Silva compass - or look at the land around you its largely enclosed water.

All said from the safety and comfort of Sydney :)

Jonathan
 
Minerva said:
Interesting question- wasn’t one of the drivers behind both GLONAS and Galileo networks that they would be independent from GPS network and not easily turned off by the yanks?
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GLONASS, Galileo, GPS and Beidou all operate on similar frequencies so its not a matter of switching them off that is the concern - a blanket interference on those frequencies can block all of them. Thats why eLoran is a proposed alternative because it uses completely different parts of the spectrum.
 
Hermit said:
GLONASS, Galileo, GPS and Beidou all operate on similar frequencies so its not a matter of switching them off that is the concern - a blanket interference on those frequencies can block all of them. Thats why eLoran is a proposed alternative because it uses completely different parts of the spectrum.
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Every day is a school day! thanks
 
mainsail1 said:
I have no idea what the word restricted means but the map shows restricted GPS all the way down the Clyde to almost Troon. It is to protect HMS Queen Elizabeth from missile attack I guess. Airspace is restricted also.
Click to expand...
Didn't somebody land a drone on her deck when she was being commissioned? RN a bit keen to avoid a repeat of that I expect.
 
Never Grumble said:
LDL, clearing bearings, navigators notebook (I used to love drawing the little sketches), plus a blind pilotage team in the Ops Room (assume they still do that).
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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.
 
Hermit said:
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.
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…. until somebody jams the GNSS (GPS et al) signals - which was where this tread started
 
Hermit said:
also, with a modern integrated navigation system, the radar and the chart work together seamlessly.
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.......until someone or something renders the GPS unreliable.
I have no experience of RN navigator training but up to my retirement in 2008 was running Radar and electronic navigation simulator courses for MN deck officers. We used integrated nav systems but also simulated GPS loss of accuracy and required cross checks on position. We also covered navigation without GPS.
 
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