Narrative:

We armed our (main) doors when the purser made the announcement. About 20 seconds later while I'm still standing at door 4R I hear the door opening. I looked at the lever and noticed it was still in the armed mode. I was about to try to stop it from being opened; but then I heard the hissing sound and thought the slide was about to blow. My flying partner grabbed me and we got out of the galley. A few seconds later I called the cockpit to advise them of what had happened and then I called the purser. Turns out the caterer had come back for some reason (he had just left) and opened the door without knocking. The door was still in the armed mode after it had been opened.

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Original NASA ASRS Text

Title: Approximately 20 seconds after flight attendants armed the B757-200 cabin doors; a truck caterer started opening door 4-Right. The external handle did not disarm the door; she heard a hissing sound from the galley ceiling area as the slide started to fall out of the slide pack and the flight subsequently cancelled.

Narrative: We armed our (Main) doors when the Purser made the announcement. About 20 seconds later while I'm still standing at Door 4R I hear the Door opening. I looked at the lever and noticed it was still in the Armed mode. I was about to try to stop it from being opened; but then I heard the hissing sound and thought the Slide was about to blow. My flying Partner grabbed me and we got out of the Galley. A few seconds later I called the Cockpit to advise them of what had happened and then I called the Purser. Turns out the Caterer had come back for some reason (he had just left) and opened the door without knocking. The Door was still in the Armed mode after it had been opened.

Data retrieved from NASA's ASRS site as of April 2012 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.