EGPWS inhibits
EGPWS only detects those ‘obstacles’ which are in the obstacle database; assuming that the option is fitted/selected and updated.
Normally there should not be any need to deactivate the ‘enhanced’ terrain features. However, rarely with new runway ends or change of circumstance, unwarranted alerts can be given; these should be notified to the system manufacturer who can modify the terrain database or provide a local GPS/FMS based alleviation.
Even if the terrain feature is inhibited then the baseline GPWS detection and alerts should still be active; which would be consistent with the NTSB briefing on the ‘Sink Rate’ alerts.
Edit: Sink Rate
SC Thanks: a typo from an earlier post where this was discussed – NTSB video briefing stated ‘Sink Rate’.
Last edited by Jetdriver; 25th Aug 2013 at 20:11.