No radar coverage when I descend into Ayers Rock or Gove. And, TCAS cannot be used for traffic separation purposes.
Related to this thread wrt compliance, it's surprising how many pilots when passed traffic, usually for a sight & pass, or a reason that climb/descent is not immediately available, reply with "yeah, got 'im on TCAS". Big deal. Saying that is as useful & relevant as saying the engines are still operating as Mr/s ATS can't use the info to qualify for separation.