On aircraft with "automatic" door/slide arming devices, and by that I mean doors which are armed/disarmed without physically touching the girt bar, how likely is it, the girt bar device may not disengage when the door is disarmed? Is this even possible?
For instance, if you disarm a 757 door, armed lever is in the disarmed position, and then you were to open the door (from the inside) is it possible the slide may still engage, or is this system relitively fail-safe? I'm sure each aircraft model differs and this is only one I used for conversational example.
I know several airlines now have simply adopted policies to not have the doors operated AT ALL from the interior, and therefore utilize a standard procedure to have doors opened/closed from the outside of aircraft to employ the use of the auto slide disengage mechanism found on most automatic doors.
I feel more comfortable with doors where you can physically see that the girt bar is NOT attached to the aircraft (737, MD80)