Ident.: DSC-25-11-20-00001007.0001001 / 10 DEC 09
Applicable to: ALL
The Cockpit Door Locking System (CDLS) provides a means of electrically locking and unlocking the
cockpit door. This system is mainly composed of :
‐ A keypad, located in the forward cabin, near the cockpit door,
‐ A toggle switch, located in the center pedestal’s Cockpit Door panel,
‐ A control unit and its CKPT DOOR CONT normal panel, located on the overhead panel,
‐ A buzzer.
The keypad enables the cabin crew to request access to the cockpit. There are two different access
request types : “Routine” and “Emergency” access request (Refer to PRO-SUP-25 Cockpit Door
Operation - General).
The toggle switch enables the flight crew to lock or unlock the cockpit door, following an access
request, thereby allowing or denying the entry to the cockpit.
The cockpit door control unit is the system controller, in charge of :
‐ Locking or unlocking the door latches, upon flight crew action.
‐ Unlocking the door, in case of cockpit decompression (the door then opens towards the cockpit
under differential pressure).
‐ Indicating system failures of electrical latches and pressure sensors.
‐ Activating the access request buzzer and turning on the keypad LEDs.
The buzzer sounds in the cockpit for 1 to 9 s to indicate that a routine access request has been
made, or sounds continuously if an emergency access procedure has been initiated.
There have been a number of posts suggesting depressurising the aircraft, the above text from the manual says COCKPIT decompression (see bold txt), so does this mean depressurising the cabin would not unlock the door until the FD had slowly reduced via panels etc, and even then as the flight deck would only reduce to the same lower cabin pressure there would not be a negative differential in the cabin so would it work?
It also says with a cabin dperessure the door would open inwards due to pressure differential, I take it it cannot open in the outwards direction even manually.