Narrative:

During push-back in the alley; the tow bar unexpectedly malfunctioned and disconnected from the tug. As the airplane was freely rolling backward; I applied braking to bring the airplane to a stop. My quick reaction averted a catastrophe; otherwise there may have been a collision with a parked airplane that was at the gate behind us. Faulty ground equipment (or) failure of the ramp crew to secure the tow bar to the tug.

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Original NASA ASRS Text

Title: An A320 Captain reported that his aircraft became disconnected from the towbar during push back but he was able to avoid a collision when he recognized the event and stopped using brakes.

Narrative: During push-back in the alley; the tow bar unexpectedly malfunctioned and disconnected from the tug. As the airplane was freely rolling backward; I applied braking to bring the airplane to a stop. My quick reaction averted a catastrophe; otherwise there may have been a collision with a parked airplane that was at the gate behind us. Faulty ground equipment (or) failure of the ramp crew to secure the tow bar to the tug.

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.