Admiralty Notice to Mariners Corrections

[zingaro]

Just bought a new set of charts Leisure chart Folio for the Irish sea-Eastern part 2nd edition ready for our summer cruise to the Isle of Man and then either Northern Ireland or maybe North Wales,been on the Admiralty site to get the Notice to Mariners for these charts so that I can apply any new corrections and noticed that the corrections are in ETRS89 Datum which I believe is the European standard and this is more accurate than the old WGS84 Datum which my new charts use,I know that differs somewhat so how do I convert the corrections to WGS84 Datum in order to make sure I put the corrections in the right Lat and Long positions. Don't ever remember having to do this when I did my Yachtmaster theory course,only thing we was made aware of was to make sure that your chart plotter was using the same Datum as your charts. Hope there are some experts out there who can explain how to do this.

 

[tillergirl]

From http://www.ordnancesurvey.co.uk/oswebsite/gps/docs/Geomatics_world.pdf

"The second coordinate system in Great Britain is
the European Terrestrial System 1989 (ETRS89).
ETRS89 is a very well defined and stable system
which is fully compatible with WGS84 (the coordinate
system used by GPS), and has been adopted as
the primary system for accurate coordinate positioning
across Europe. Unlike WGS84 however,
ETRS89 is fixed at a point in time and does not
move with the motion of the Earth’s tectonic plates.
The difference between WGS84 and ETRS89 is now
approximately 15 cm (they were synonymous in
1989)."

I'm not sure I be bothered to worry about 15cm!

 

[dt4134]

Admiralty charts are ETRS89 they just say you can plot WGS84 positions on them.

 

[Kawasaki]

WGS84, is ok Mate
Just remember to applie the (about 4 degrees West) to your compass hereabouts.
Might make a difference to 'hitting' Port St Mary as opposed to Douglas!

 

[hlb]

I'd fit some thicker fenders to cope with the 15 cm.

 

[zingaro]

Thanks everyone for the answers,I shall now get on with the chart corrections,don't worry I shall apply the 4 degrees variation,to give me magnetic and then the deviation to give me compass. Then I will throw my charts in the cupboard and use waypoints on my electric thingy majig,think they call them chartplotters,but will save that for another day,lol