Originally Posted by flensr

You're ok with it because you haven't read through the accident reports from the false glideslope lock-on mishaps that happened in the past. Or you did but you've forgotten them. I have no idea if the technology in our receivers has been updated to better reject false glidepath lock-on, but this is one of the primary reasons why we're supposed to verify the final approach fix and altitude on instrument approaches. The USAF found out the hard way and before they implemented a universal rule about identifying the FAF before starting down, they planted a few in the dirt several miles short of the runway from false ILS glidepath lock-on mishaps.

Yea, it "never happens". Except it did before the procedures were the way they are today, and they all died miles short of the runway on centerline with the needles centered. So we're supposed to take a couple of steps in order to help make sure it doesn't happen to us. As far as I know, since the tighter ILS procedures have been adopted there hasn't been a false glidepath lock-on mishap in the US. That doesn't mean the threat isn't there, because the underlying technology is still the same. It simply means we're doing it right and our procedures are working.