Thanks again, sp. Your point about the crew's responsibility for being clear of false signals is one I referred to earlier in this thread (23 Dec 10:53) so I agree there. I do have the AIC you refer to, but it is not quite detailed enough. Interestingly, the reference to "where special approach procedures have been devised in which the Glide Path may be joined from above..." takes us right back to my original question, i.e. "Where might that be then?"