Jet II
I do not condone the actions of the Flight Crew here at all, and reading through the lines, nor the does the author of the CHIRP comments.
However:
<<Once all the passengers had disembarked both flight crew attempted to disarm the door and both confirmed they were unable to successfully do so>>
<<Therefore both flight deck members knew that the door was faulty - this is not a 'grey area' - if the door is u/s then it must be considered an inoperative exit in accordance with the MEL>>
Bear in mind the number of doors required is the number of EMERGENCY exits. Therefore, if it could be established that the door would operate in an emergency mode i.e. slide would inflate, then the fact it could not be disarmed might not matter.
Whatever, the MEL should should have been consulted. It is for the MEL to state what "Door U/S" means... It would almost certainly have been subdivided into which part of the door was u/s, and the appropriate limitations stated.
In practice, I cannot see how, as Flt Crew, I could make the judgement on whether it would operate. Only an engineer can state that against a Tech log entry.
NoD