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glhcarl
I do not know of Af has technical assistance at DUS, but if we have a techincal problem, but are to depart with that item unservicable, we just fill in the books and leave the problem to be fixed at home base.
So depending whatever the books say about flying with a smoke detector inop, it could well be that they did find it to be inop at say startup or so, but could fly home and there they found te reason for it to be inop.