Correcting paper charts - a few thoughts...

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Babylon

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Have spent several evenings over the last few weeks working on correcting my small but growing collection of Admiralty Leisure charts (3 folios plus a few extra charts). The job's not yet finished, mainly because each folio contains up to about 20 charts, and also my main folio for home waters, The Solent, only purchased in 2007, has subsequently gone through two further editions. My thoughts:

* There's nothing like correcting charts to really get familiar with what chart symbols and notations mean, especially the ones you've gone hazy on.

* What starts out as a virtuous excercise for each chart or folio soons becomes an exercise in deciding what you DON'T need to correct (eg a change in depth mid-channel from 19 to 18m, or a minor shift of transit marks into a naval dry dock).

* For a folio covering areas like the Solent that are revised with a new edition almost yearly, its a pretty large job to download three years' worth of NMs and correct the whole lot. At £45 for the latest edition, correcting nearly 20 charts from a total of about 40 pages of NM downloads (3 years' worth) strikes me as slavish persistence - but I've started the job so I'll d@mn well finish it!

* In future I must check and download corrections at least yearly.

* By correcting charts, I've found myself wondering about places not far from home which I've never been to before, but which I'd now like to (especially to avoid the more congested destinations!).

Any other thoughts?
 
Yes; it is a good exersise as you say.

Once did this and found one French coast buoy appeared to move 100 metres or so two, three or four times a year. Thus when it was not where I exoected to find it I was confident it was on little consequence.

Equally as our plotter removes important items like rocks depending on zoom level , I have known that I must pass south of the south cardinal even when the plotter shows no depth less than 4m. I am old fasion and assume rocks do not move!
 
I'm a shorebased instructor but what follows is definitely not what I teach the students.

Personally I never correct charts. Every few years I replace one or two particularly for the areas I use most. But then my chart plotter data is 5 years out of date at least.

Much of the information on charts which generates a correction notice is relevant only to big ships - I don't navigate using the channel markers and I keep a good enough watch to see and avoid cardinals. Rocks dont move and the sand banks that do move and are charted are mostly only those relevant to big ships. The shallow areas we use are rarely if ever surveyed so in thinking that by updating your charts you know where the sandbanks are at the edge of the channel ( ie within the 5 metre contour) you are mistaken.

Pilotage is by eyeball and in any case the annual almanac gives me reasonably up to date pilotage info.

In short I reckon that by keeping a good watch and planning cautious routes, you dont really need to update charts . And the low incidence of marine accidents combined with the small percentage of sailors who do update their charts suggest I'm right.

Or maybe just lazy! :eek:
 
Bosun Higgs said:
I'm a shorebased instructor but what follows is definitely not what I teach the students.

Personally I never correct charts. Every few years I replace one or two particularly for the areas I use most. But then my chart plotter data is 5 years out of date at least.

Much of the information on charts which generates a correction notice is relevant only to big ships - I don't navigate using the channel markers and I keep a good enough watch to see and avoid cardinals. Rocks dont move and the sand banks that do move and are charted are mostly only those relevant to big ships. The shallow areas we use are rarely if ever surveyed so in thinking that by updating your charts you know where the sandbanks are at the edge of the channel ( ie within the 5 metre contour) you are mistaken.

Pilotage is by eyeball and in any case the annual almanac gives me reasonably up to date pilotage info.

In short I reckon that by keeping a good watch and planning cautious routes, you dont really need to update charts . And the low incidence of marine accidents combined with the small percentage of sailors who do update their charts suggest I'm right.

Or maybe just lazy! :eek:
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Wot he said x 2 even if it is heresy!

Important changes like when the Ushant TSS was moved a few years back justify new charts but mostly the changes are minor. As far as lights are concerned the latest Lights List helps and is in the Almanacs. I did always print out the changes from Imray's site for my charts and keep the printout with them as a reminder to look up anything that might affect us but it rarely did.

Changes of all kinds take months to get into Notices anyway and some are out of date even before they get that far. Commonsense is the key. Probably 90% or more of trips are repeat ones for which waypoints and routes are loaded in the electronics anyway so the fact that there is now a new fish farm half a mile off the route is largely academic. Going to a new area would usually mean new charts anyway.
 
Robin said:
I did always print out the changes from Imray's site for my charts and keep the printout with them as a reminder to look up anything that might affect us but it rarely did.
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Thats what I do, print out the changes and keep with the charts, occasionally mark up relevant (to me) changes, you would have to be seriously short of a hobby and freinds to keep all charts permanantly up to date with every change.
 
Babylon said:
* By correcting charts, I've found myself wondering about places not far from home which I've never been to before, but which I'd now like to (especially to avoid the more congested destinations!).

Any other thoughts?
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Like Babylon I correct my Admiralty charts (folios) - I'm not sure its of any real use to me but I do enjoy studying those backwaters where I suspect I'll never go - Frustration when you carefully plot and mark a new buoy only tto have it removed on the following page of corrections!

As for my Imray charts, presumably there is no correction available for these?

JuSW
 
Bosun Higgs said:
Rocks dont move and the sand banks that do move and are charted are mostly only those relevant to big ships.
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Even if you don't correct charts it is still useful to keep an eye on the NMs. Agreed, rocks don't move, but they mave have been charted incorrectly in the past, or may not have been discovered until recently.

Alisdair
 
[QUOTE
As for my Imray charts, presumably there is no correction available for these?

JuSW[/QUOTE]

Imray chart corrections are available as downloads through their website. I print them off at the start of the season, when I'm feeling fresh and enthusiastic, but as others have said, many of the changes are of no consequence. I suppose most years I'll go through the corrections, make a few that I think I might want to know about, and ignore the rest - after making a conscious decison to do so.

I spent a lot of time on Lake Vicoria last winter - the area I was in was last charted in 1912! The banks in some areas move almost daily and I saw a floating island, maybe 100m long, move across the bay one day. A sounding pole (ie an oar) and a good lookout were the best we could do. And if you think poorly marked lobster pots are a problem - try spotting fishing nets supported by inflated, discarded plastic bags and milk sachets!
 
It's nice to know one is not alone. ;)

A chart, like a map, or a business plan, is only a guide as to what you might expect to find. All man made stuff is liable to change as are sandbanks. But it never fails to amaze me how little actually changes much, given the storms that hit the shallow waters I mostly frequent.

If I'm approaching a new anchorage/ harbour (a pretty rare event these days!) or one I haven't used in a while, I refer to the charts & pilot books (I have several covering my area over the last 100 years) and use my eyes & brain.

The uncertainty keeps one alert & observant - an excellent safety feature. The last thing you want is "total confidence" in your charts!!! :eek:
 
A salutary tale for all you "rocks don't move" heretics. A bit north of Fladda on the much travelled route north to Oban and the Sound of Mull from Kintyre and Crinan via the Sound of Jura is a wee jaggy lumpy bit called Bono Rock. There used to be a red can buoy parked on top of it and for most yachts as long as you missed the buoy you were safe. Then the powers that be moved the buoy a bit northeast which gave a bit more clearance if you passed it to port (like you should) but the effect was that several boats managed to bang their keels doing what they thought was the same thing they'd been doing for years. I'm glad to say that the NLB have now stuck a west cardinal next to the rock.
One of the changes I do make to my charts is the repositioning of buoys - there are a surprising number of moves (followed quite often with a move back again several nms later).
 
Bosun Higgs said:
In short I reckon that by keeping a good watch and planning cautious routes, you dont really need to update charts . And the low incidence of marine accidents combined with the small percentage of sailors who do update their charts suggest I'm right.
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I'm with you on this. I sail the West Coast of Scotland with a 1936 CCC Sailing Directions and a pile of charts which have remained resolutely uncorrected over 20+ years. I do make sure that I have an up-to-date list of lights, though.
 
Babylon said:
* For a folio covering areas like the Solent that are revised with a new edition almost yearly, its a pretty large job to download three years' worth of NMs and correct the whole lot. At £45 for the latest edition, correcting nearly 20 charts from a total of about 40 pages of NM downloads (3 years' worth) strikes me as slavish persistence - but I've started the job so I'll d@mn well finish it!
Click to expand...

How do you get notices for mariners for non-current editions then? The only notices to mariners I can find for SC5600 are for the 12th edition: this is pretty useless for someone with the 10th edition (who can't access corrections for the 10th and 11th editions). I'm looking at this URL:

http://www.admiraltyleisure.co.uk/ALDNMs/5600SC5600_The_Solent_and_Approaches.pdf

I'd really like to know how I can access these old NMs.
 
Babylon said:
Have spent several evenings over the last few weeks working on correcting my small but growing collection of Admiralty Leisure charts (3 folios plus a few extra charts). The job's not yet finished, mainly because each folio contains up to about 20 charts,

Any other thoughts?
Click to expand...

I think it pays to concentrate your routine on the locations where changes are important even critical:

1.There are places around your crusing ground where the seabed changes shape - the Thames is a good example - and staying in touch with changes to boyage, or silting of shallow passages, is a natural.
Worth scanning the monthly notices for items relating to such places.

2. The there are changes to navigation systems, the Sunk off Harwich is a good example, where the changes are major and patching is often not worth the effort- new chart!

Small scale charts are hardly ever worth the effort.

All the rest is worth only a scant look each month. We all start with a few charts and make meticulous corrections, but then settle into the more selective routine when correcting 30+ charts every year in full detail would be needlessly onerous.

PWG
 
zlod said:
How do you get notices for mariners for non-current editions then? The only notices to mariners I can find for SC5600 are for the 12th edition: this is pretty useless for someone with the 10th edition (who can't access corrections for the 10th and 11th editions). I'm looking at this URL:

http://www.admiraltyleisure.co.uk/ALDNMs/5600SC5600_The_Solent_and_Approaches.pdf

I'd really like to know how I can access these old NMs.
Click to expand...

The UKHO website only has NM's for the current edition of any chart. The only way you could correct an older one is if you can find someone with the old corrections, or buy the new edition.
 
Older Solent NMs

ZEBEDEE said:
The UKHO website only has NM's for the current edition of any chart. The only way you could correct an older one is if you can find someone with the old corrections, or buy the new edition.
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Correct. The only reason I happen to have the NMs for the 10th (2007) and 11th (2008) editions of the Solent Folio (SC5600), as well as the current 12th (2009), is that I downloaded them each year just before they were removed from the Admiralty website.

If anyone wants these older NMs, then PM me with an email address and I'll be happy to send the PDFs on.
 
awol said:
A salutary tale for all you "rocks don't move" heretics. A bit north of Fladda on the much travelled route north to Oban and the Sound of Mull from Kintyre and Crinan via the Sound of Jura is a wee jaggy lumpy bit called Bono Rock. There used to be a red can buoy parked on top of it and for most yachts as long as you missed the buoy you were safe. Then the powers that be moved the buoy a bit northeast which gave a bit more clearance if you passed it to port (like you should) but the effect was that several boats managed to bang their keels doing what they thought was the same thing they'd been doing for years. I'm glad to say that the NLB have now stuck a west cardinal next to the rock.
One of the changes I do make to my charts is the repositioning of buoys - there are a surprising number of moves (followed quite often with a move back again several nms later).
Click to expand...

The problem arose because those travelling north and south were safer with the new position but boats going west from Cuan Sound were turning toward SW Mull after passing the buoy and finding themselves right on top of the rock. You would think they might have been able to anticipate the problem, but as someone has said, they were thinking 'ship' and very few of them use Cuan Sound.
 
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