Originally Posted by
nancypants
Not an aircraft i’m hugely familiar with but from the looks of it that’s how the pin is when disarmed- the clear plastic flap covers the armed/disarmed lever, thus:
Door disarmed, pin in disarming mechanism
Door armed, pin removed
This is correct. It is an Airbus feature, and can also be found on both the A320 and A321 aircraft I used to work on. Airbus doors are very similar, even across model lines. When disarmed, the pin is placed into a slot in the arming lever to lock it in place. Once the door is armed, it is stowed either in a pouch attached to the door, or a slot on the hinge as shown in the OP. This is an airline preference; at my company, it was stowed into the hinge on the main doors (type A doors, 1L/1R and 2L/2R on the A320, 1L/1R and 4L/4R), and a pouch was used on the mid-cabin doors on the A321 (type C doors, 2L/2R and 3L/3R). The hinge slot is empty and is simply just a place to keep the pin.
I once almost had a flight deplane because a customer decided they liked the RBF tag and let it conveniently "fall" into their bag. When the police showed up, it "magically" appeared under the customer's seat.
Type A door, with the pin at 1:47:
Type C door:
-J.