GPS and non- WGS-84 co-ordinates.
 

>

There is a note in the A318/319/320/321 FCOM 4.05.30, stating that we should deselect GPS as a navigation source for takeoff when operating from airports where there is a difference between the local co-ordinate system and WGS-84, to avoid a possible map shift on application of take-off thrust. Did you ever come across this situation and what airports/countries are affected. Jeppesen has a table (updated Oct 01) for compliant countries at http://socrates.jeppesen.com/onlinepubs/wgs-84.phtml

<

Any ideas?

I ts in all the FCOM's, mainly there due to regulatary pressures.
Never given me any problems anywhere in the world but to be remembered and acted on if necessary.