S2K
It's true that the majority are not GPS approach rated, however there is nothing to stop them superimposing a GPS pointer to suppliment the ADF pointer - many do this, it's perfectly legal and good practice IMO. Of course if there were significant differences in ADF and GPS tracking information, the approach would need to be discontinued.
MOR
I think that the types of aircraft with old ADF equipment that are likely to be more affected by any preculiarities, are unlikely to be GPWS equiped. I don't know if you've noticed, but many ADFs in 30+ year old light aircraft leave a lot to be desired in the traking stakes. This is just an observation, and certainly not a commentry on the recent tragic events - like every one else, I will wait for the report.
Last edited by Cloud Cutter; 6th Feb 2005 at 06:48.