Originally Posted by
Roj approved
On the A320 (and I suspect all Airbus, and pretty sure the same on the 787) the PA handset is wired to the hot battery bus, so it will always work. ie: after both engines and APU are shutdown via the fire PB in an evacuation you can easily make the announcement via the Handset.
Only Capt side audio selector works but needs to be reselected after power transfer to use the radio or the PA button. (Often forgotten in the mad rush of an evac)
So in the spirit of “practice what you play”, if you get in the habit of using the PA handset for all cabin announcements, when you come to a real emergency, your muscle memory will reach for the handset and the message will get through.
RTO for example, “STOP” -> REV Thrust -> IDLE -> Park Brake On -> PA handset. It’s a very simple movement of the hand in the same direction.
As for the volume as mentioned by the OP, never heard that, don’t know the answer. Some of our a/c are really loud, some not so loud.
For an RTO followed by an EMER EVAC, there are 2 calls using the PA system.
1. CABIN CREW (PA) ... ALERT: The FCTM RTO Flow Pattern is suggesting the ACP PA button should be used.
2. EVACUATION .... INITIATE: Nothing is specified, but I normally use the ACP PA button to save time prior to pressing the EVAC COMMAND button.
Also, the ACP PA button is momentary and does not need to be re-selected after transfer to hot bus battery power (I think...).