Yes, for those aircraft that are carrying and using the appropriate transponders, the Mode-S trials have been useful.
The UK is not going to be introducing Elementary Mode-S in 2003 as per the remainder of the Eurocontrol states, but is going straight to Enhanced Mode S in 2005. Mode S will be introduced into the Terminal Control environment initially. The prime driver to do so is a safety one, namely to use the Selected Altitude parameter to reduce the number of Level Busts that occur. Additionally Mode-S will provide 25ft height reporting intervals which will enable the STCA to be further refined. Not that TC needs STCA
