Originally Posted by
RUMBEAR
I believe the “emergency descent” PA is for the benefit of the Cabin Crew. I.e so they know the flight crew are not incompacitated. Depending on company SOP, the cabin crew may attempt to enter the cockpit if the PA is not announced.
Having worked for QF and now retired, as long as procedures haven’t changed, the PA was for crew and PAX as a backup to the recorded PA and to reassure them the pilots were carrying out the procedure.