Narrative:

We arrived at the aircraft for the orientation preflight and discovered that it was the same aircraft we had brought in the previous evening. The flight attendant reported that she distinctly remembers disarming the door evacuate/evacuation slide the previous evening upon arrival at the gate. She was visibly upset when we arrived at the aircraft the next morning only to find the slides had been armed sometime during the night. It's beyond me how or why this could happen, but it is obviously a very dangerous situation. We figured that perhaps the aircraft had to be moved during the night and that the doors may have been armed at that time, but not disarmed. I don't know, but if there is anybody in the system that arms or disarms aircraft doors besides flight crew's, they should be reminded of the importance of making certain they are disarmed.

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Original NASA ASRS Text

Title: MD80 CREW FOUND THAT SOMEONE HAD ARMED THE EMER EVAC SLIDES ON THE OVERNIGHT STAY.

Narrative: WE ARRIVED AT THE ACFT FOR THE ORIENTATION PREFLT AND DISCOVERED THAT IT WAS THE SAME ACFT WE HAD BROUGHT IN THE PREVIOUS EVENING. THE FLT ATTENDANT RPTED THAT SHE DISTINCTLY REMEMBERS DISARMING THE DOOR EVAC SLIDE THE PREVIOUS EVENING UPON ARR AT THE GATE. SHE WAS VISIBLY UPSET WHEN WE ARRIVED AT THE ACFT THE NEXT MORNING ONLY TO FIND THE SLIDES HAD BEEN ARMED SOMETIME DURING THE NIGHT. IT'S BEYOND ME HOW OR WHY THIS COULD HAPPEN, BUT IT IS OBVIOUSLY A VERY DANGEROUS SIT. WE FIGURED THAT PERHAPS THE ACFT HAD TO BE MOVED DURING THE NIGHT AND THAT THE DOORS MAY HAVE BEEN ARMED AT THAT TIME, BUT NOT DISARMED. I DON'T KNOW, BUT IF THERE IS ANYBODY IN THE SYS THAT ARMS OR DISARMS ACFT DOORS BESIDES FLT CREW'S, THEY SHOULD BE REMINDED OF THE IMPORTANCE OF MAKING CERTAIN THEY ARE DISARMED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.