Hector_Pascal
Let me explain my orginal (somewhat tongue in cheek) post
The Times Jorno insinuated that it was not working because it gave a warning at 500 ft on approach to GIB. My point was if yo're aiming at the base of the rock of Gibraltar where the threshold is, I would assume that when the GPWS gives a warning it was infact working correctly and that it should not be classed as a fault as it is letting you know that your heading for a big rock which is it's job.
However I'm no pilot or engineer, you are and I accept your views & point about assumption.