The moral of the bstory/b is that GPS is a great tool, but, like any other navigational system, it has limitations. GPS receivers can and do fail, so pilots should understand the limitations of GPS, know how to do a RAIM prediction, ... Yes, I 've seen GPS reliability warnings for areas around the China bLake NAS/b and Fallon NAS. Dave, Thanks for the clarification regarding WAAS satellites. Even the venerable ILS is not immune to problems. There was a good article a few years ...
