Narrative:

After numerous pre-departure delays I finally closed the right crew entry door and armed the slides for the right and left doors; then returned to the cockpit and closed and locked the cockpit door. We ran the before start checklist down to the line; but could not complete it because we had not yet received the final weight and balance and also the lower aft cargo and aft bulk cargo doors were still indicating open on the ECAM. The crew stairs were still in place on the right side of the aircraft. After about 10 minutes I noticed movement on the crew stairs on the right side of the aircraft. A ramp employee came up the crew stairs; opened the armed right crew entry door; entered the aircraft; and closed the door. I got out of my seat and went to the back to determine why he had just entered the aircraft. My initial concern was the armed door and slide; and I apparently made the error of moving the slide arming handle from what I thought was the armed position to what I thought was the safe position. I knew that opening the armed door from the outside should not deploy the slide; but did not recall that raising the outside door handle also moves the arming handle to the safe position. I should have read the markings on the arming handle and ensured that the arming handle was in the safe position. I then turned to the ramp employee and asked him why he had entered the aircraft through the armed door. He replied that he was looking for the ramp agent and still had some paperwork to complete. I believe he had assumed that the door was disarmed because the stairs were still in place. I then returned to the cockpit to advise the captain of the situation. A very short time later; I heard the beep of the warning tone which only goes off when the crew entry door handle is being raised with the slide armed. Upon hearing the door opening I quickly went to the aft cabin in time to witness the open crew entry door and the slide inflating and extending. The ramp employee had attempted to exit the door; but the door blew open and the emergency slide had deployed. The next thing I noticed was that the crew stairs had already been removed from the aircraft. The ramp employees working outside the aircraft appeared unaware the ground crewman was still on the aircraft. Minutes later the captain contacted operations; advised them of our slide deployment and requested maintenance personnel to the aircraft. I then called down to the ramp employees below and requested that they move the stairs to the door on the left side of the aircraft. Maintenance came to the aircraft; removed the slide; and deferred the door and slide as 'crew entry door/escape slide inop.' no one was injured in the incident.

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Original NASA ASRS Text

Title: Confusion as to the emergency slide status of an A310 resulted in a ground crewman attempting to exit the aircraft just prior to gate departure; blowing the door open and deploying the slide.

Narrative: After numerous pre-departure delays I finally closed the right crew entry door and armed the slides for the right and left doors; then returned to the cockpit and closed and locked the cockpit door. We ran the Before Start Checklist down to the line; but could not complete it because we had not yet received the final weight and balance and also the lower aft cargo and aft bulk cargo doors were still indicating open on the ECAM. The crew stairs were still in place on the right side of the aircraft. After about 10 minutes I noticed movement on the crew stairs on the right side of the aircraft. A ramp employee came up the crew stairs; opened the armed right crew entry door; entered the aircraft; and closed the door. I got out of my seat and went to the back to determine why he had just entered the aircraft. My initial concern was the armed door and slide; and I apparently made the error of moving the slide arming handle from what I thought was the armed position to what I thought was the safe position. I knew that opening the armed door from the outside should not deploy the slide; but did not recall that raising the outside door handle also moves the arming handle to the safe position. I should have read the markings on the arming handle and ensured that the arming handle was in the safe position. I then turned to the ramp employee and asked him why he had entered the aircraft through the armed door. He replied that he was looking for the Ramp Agent and still had some paperwork to complete. I believe he had assumed that the door was disarmed because the stairs were still in place. I then returned to the cockpit to advise the Captain of the situation. A very short time later; I heard the beep of the warning tone which only goes off when the crew entry door handle is being raised with the slide armed. Upon hearing the door opening I quickly went to the aft cabin in time to witness the open crew entry door and the slide inflating and extending. The ramp employee had attempted to exit the door; but the door blew open and the emergency slide had deployed. The next thing I noticed was that the crew stairs had already been removed from the aircraft. The ramp employees working outside the aircraft appeared unaware the ground crewman was still on the aircraft. Minutes later the Captain contacted Operations; advised them of our slide deployment and requested Maintenance personnel to the aircraft. I then called down to the ramp employees below and requested that they move the stairs to the door on the left side of the aircraft. Maintenance came to the aircraft; removed the slide; and deferred the door and slide as 'Crew Entry Door/Escape Slide Inop.' No one was injured in the incident.

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.