Narrative:

I was assigned to move an A320 aircraft from the gate to the hangar. Mechanic Y unplugged the power cord and went in the aircraft and closed the door and started the APU. I was in the tractor [tug]. I got out of the tractor and pulled the [wheel] chocks. I got back in the tractor and was preparing to approach the aircraft. I then saw the aircraft rolling back away from the jetway. I called on the radio for mechanic Y to set the brakes; he did and the aircraft stopped. There were no injuries or aircraft damage. The brakes on the aircraft were not set upon entry to the aircraft and we received no notification that the brakes were released for any reason.

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Original NASA ASRS Text

Title: Two line mechanics preparing to move an A320 aircraft from a terminal gate to their hangar; report the aircraft had rolled back from the jetway after they had removed the wheel chocks.

Narrative: I was assigned to move an A320 aircraft from the gate to the hangar. Mechanic Y unplugged the power cord and went in the aircraft and closed the door and started the APU. I was in the tractor [tug]. I got out of the tractor and pulled the [wheel] chocks. I got back in the tractor and was preparing to approach the aircraft. I then saw the aircraft rolling back away from the jetway. I called on the radio for Mechanic Y to set the brakes; he did and the aircraft stopped. There were no injuries or aircraft damage. The brakes on the aircraft were not set upon entry to the aircraft and we received no notification that the brakes were released for any reason.

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.