Chartplotters - another enthusiastic convert . . .

[Sixpence]

I got the aerial sorted a month ago then got the power wired in the other day. Guess what? No signal.

Hopefully I'll be coming your way in the not too distant future and I'll sort it out so it works then
Bleedin coppers don't know sod all about wiring

 

[Twister_Ken]

"Bleedin coppers don't know sod all about wiring"

'ang on - what about copper wiring?

 

[Sixpence]

"Bleedin coppers don't know sod all about wiring"

'ang on - what about copper wiring?

Ken
Every fule knows ewe don't use just any copper wiring

 

[mortehoe]

Oh Dear .... "Using the cursor to enter waypoints ....."

Forget the AIS ... What would be more beneficial to sailorkind is a sensor/alarum system to identify pot lines especially of the 7x19 S/S kind.

It's absolutely appauling that you should have go anti-clockwise round Ireland with a non- scratch crew ... handicapp 36+ perhaps! (Don't answer!)

M

 

[Danny Jo]

Forget the AIS ... What would be more beneficial to sailorkind is a sensor/alarum system to identify pot lines especially of the 7x19 S/S kind.

It's absolutely appauling that you should have go anti-clockwise round Ireland with a non- scratch crew ... handicapp 36+ perhaps! (Don't answer!)

M

Hey! Never mind my scurrilous innuendos about crew skills - shouldn't you be mowing the lawn before the rain comes?

In spite of your entreaty not to answer, your breaking of cover forces me to put the record straight: the only complaints I have about the crew was that they had an uncanny knack of helming through overfalls inadequately clad. (Even so, I'll never believe that the water in their boots was from the sea.)

 

[maxi77]

Doghouse,

Reports are that the USAF is already way behind on the spending, that redundancy is fast running out on existing satellites and the 95+% coverage we enjoy now will be down to 70 - 80 % next year. It is too late, the Americans have already let the standard drop. It just depends where the 20 -30% is. Hopefully it will mean we are watching 4 satellites rather than 6 or 7, but maybe we will only see 2.....

If one considers the reliance the US forces and civil users of GPS have on the system I do not see them running out of satelites that soon. I understand that in fact what is happening is that the number of 'spare' satelites is falling as the US prepares to launch a whole new series of satelites to provide a higher precision service

 

[wotayottie]

I guess my problem could be that the Raymarine C80 is outdated, but having this year acquired a boat with one on board, I still find myself using paper. Route planning on a small screen is so much more difficult, the plotter is below decks with no repeater at the wheel, updating the charts is expensive, and somehow the user interface is cumbersome and far from obvious. The lappy plotter I have used is far better in that respect.

So going through the Nash passage into Swansea bay yesterday, it was a case of having the folio page at my side at the wheel, plus handbearing compass and pencil to navigate mostly by eye.

Yet I would class myself as being more toward the geeky end of the scale than the luddite end.

If it wouldnt leave a nasty hole in the woodwork, I think I'd flog the plotter.

 

[snooks]

Waypoints! You are oh so 20th century, get with it man.

All you have to do is head out of harbour and when the floaty red and green things finish you turn the wheel until the long black "this is where you are going line" on the little TV screen at the wheel, cuts through the name of the port where you want to go.

Ah, but when you sail as slow as we do, we do all our tidal calculations so we won't have to head "up hill" at the end of it when tide has set us down 3 miles.

That way we sail the shortest route

 

[AntarcticPilot]

Forget the AIS ... What would be more beneficial to sailorkind is a sensor/alarum system to identify pot lines especially of the 7x19 S/S kind.

It's absolutely appauling that you should have go anti-clockwise round Ireland with a non- scratch crew ... handicapp 36+ perhaps! (Don't answer!)

M

What I want is an option on the AIS menu saying "Don't tell me about things I already know about!"

 

[dukes4monny]

My cockpit mounted CP is used to back up my cabin mounted GPS and charts. I read a thread on here recently of a yacht entering Paimpol (I think) and they hit a rock which didn't show up on the CP........but it did show up on the charts.
I like this quote which is from a navigation book I have by Captain Bill Brogdon: "Just remember that these systems aren't a substitute for thinking. Error's show up, receivers fail, and it is easy to misuse their complex features".

 

[wotayottie]

What I want is an option on the AIS menu saying "Don't tell me about things I already know about!"

Can SWMBO be fitted with that facility?

 

[glashen]

Doghouse,

Reports are that the USAF is already way behind on the spending, that redundancy is fast running out on existing satellites and the 95+% coverage we enjoy now will be down to 70 - 80 % next year. It is too late, the Americans have already let the standard drop. It just depends where the 20 -30% is. Hopefully it will mean we are watching 4 satellites rather than 6 or 7, but maybe we will only see 2.....

Try this report quoting USAF saying No Problem, http://abcnews.go.com/Technology/AheadoftheCurve/story?id=7647002&page=1

Thing is, the worst I would expect from a marine POV is that you have to have a look around and verify your position, The US military would have bigger problems if the accuracy was significantly degraded.

 

[wotayottie]

the US military use a different system and have the ability to move satellites to areas of likely activity. They have no real interest in the civvy set up except that it was the civvy set up that got them the money for their toys.

 

[andygc]

the US military use a different system and have the ability to move satellites to areas of likely activity. They have no real interest in the civvy set up except that it was the civvy set up that got them the money for their toys.

I think you might have got something a bit mixed up there. There is no civvy system, there's a military system managed by the USAF which is available to anybody with the right type of receiver. The signal used to be deliberately degraded all of the time (selective availability - SA), but the USAF switched that off in 2000 as it could be countered by differential GPS using land-based stations as reference points. If the US wishes SA can be switched back on, but that would be a major problem for commercial aviation and shipping and would be very costly for US trade.

The satellites cannot be "moved to areas of likely activity" - they are not geostationary satellites. The system depends on the satellites moving in known orbits. The orbits can be adjusted, but that is nothing to do with "likely activity". There is a very detailed article on GPS in Wikipedia.

 

[fishermantwo]

My cockpit mounted CP is used to back up my cabin mounted GPS and charts. I read a thread on here recently of a yacht entering Paimpol (I think) and they hit a rock which didn't show up on the CP........but it did show up on the charts.
I like this quote which is from a navigation book I have by Captain Bill Brogdon: "Just remember that these systems aren't a substitute for thinking. Error's show up, receivers fail, and it is easy to misuse their complex features".

Of course that would not happen if he had been using a computer as a chart plotter. With a computer that uses digital charts, nothing disappears when you zoom in or out. No comparison between a computer and a fiddly little CP although I do use one as a back up.

 

[smartcom]

GPS scaremongering

Whilst it is true that the GPS system is a bit behind on launching some of the replacement satellites, and this will reduce the number of operational satellites over the next few years, some things to bear in mind are:
- the press releases that kicked this off are part of a fight for budget in the US, so paint worst case scenarios
- for general marine use it is not forecast to be a problem, at least for position fixing within the accuracy of the charts. High precision users such as surveyors are already noticing a reduced satellite coverage, and it will also be noticed by satnav users due to buildings obstructing skylines in urban areas
- in the longer term things will be back on track, the problem is just with the current batch of satellites being behind schedule and over budget from the manufacturers.

Of the other GNSS systems, the Russian Glonass has had large investments in it and is almost at fully operational status - this is scheduled for the end of this year, I believe. Surveyors etc have been using combined GPS/Glonass receivers for years. Galileo isn't going to be around until 2013 at the earliest, and although the Chinases are making fast progress with Compass their last satellite failed soon after launch. Hopwever in time we will get general marine GNSS receivers that will use all available satellites, especially as there is a common standard for signal structure (except for the older Glonass satellites, though the latest satellites will be dual operational, so GPS compatable).

The other thing that is coming soon is eLoran. This is basically Loran on steroids, giving 8-20m accuracy. In fact the NW Europe Loran chain is still in operational, if you have an old receiver anywhere, though only the UK transmitter has been upgradeed to eLoran as far as I know (moved from Rugby to the lake district). eLoran will also be proof against GPS jamming exercises by the military, and other sources of interference.

Regarding the ability to "steer" the GPS system, although theyt are not geostationary satellites this can be, and is, done. The orbits of the satellites are changed to give denser coverage over certain parts of the world. It is probably no surprise that this is presently concentrated over the middle east, due to the US invasions of Iraq and Afghanistan.

 

[Danny Jo]

Whilst it is true that the GPS system is a bit behind on launching some of the replacement satellites, and this will reduce the number of operational satellites over the next few years, some things to bear in mind are: . . .

Er, Smartcom, I think you've come to the wrong forum. Scuttlebutt is for people who don't know what they are talking about. [/SMARTRS IRONY OFF]

Seriously, though, thanks for your very informative post.

 

[Refueler]

If one considers the reliance the US forces and civil users of GPS have on the system I do not see them running out of satelites that soon. I understand that in fact what is happening is that the number of 'spare' satelites is falling as the US prepares to launch a whole new series of satelites to provide a higher precision service

At last a breath of fresh air ... True. US put up spare sats to take over in case of any failures. It is those that are now being used up while USofA sorts out the mess they got in for launch systems and the new generation sats. Lack of investment over years left US Air Force short on funds to service sat launches and updating of systems. It is also that the ground tracking stations / data systems are in need of servicing.

That's my understanding of the Report issued by the Auditing Co. in USA ..

 

[Refueler]

Yep - the catch is the ease of use and it soon starts to reduce the paper chart use. I carry paper charts but often they stay in the tube ... only charts I get out are port approach charts ....

Last trip just 2 weeks ago - I got news that Mother passed away ... the CP shone through as we quickly re-routed to return home and for me to fly to UK. Time taken to re-route ? Seconds instead of minutes.

Even before then - we'd had change of wind direction / weather to forecasted ... change plans on screen and head to different destination ... CP does it nicely as you can set to the wind ... see where heading line indicates on CP ... find nearest spot to go to ...

 

[alan]

As they rely upon the GPS I can foresee huge queues at the sailing schools/adult education centres in the future when the satellites begin to pack up and the USA cannot afford to replace them which is forecast to happen within the next 10 years or so. Don't throw your paper charts away yet, and keep them up to date.

Yeah, but we'll have Galileo by then !!!!!!!!!!!!!!!!!! (this is an inside joke as I work on part of the Galileo project and of course it's on schedule .................. which schedule is another question!!).

Alan.