False glideslope capture:
Monitor ground speed and anticipate ROD based on the glide requirement. Does it look right? How does altitude look against the DME (the old 300 feet/nm on a 3 degree etc..)? How does altitude compare at the check altitude?
If something is amiss either: Check with ATC, initiate a go-around or if both pilots have confirmed that there is a glide slope issue and the aircraft is no danger and within tolerances at that point, then use raw data, assume LLZ only and use plate info to manually execute the approach
bearing in mind the new MDA.
Depends on your SOPs of course.
