Narrative:

Our push back crew failed to secure the tow bar to the pushback vehicle; resulting in the aircraft being pushed back without control. I applied brakes gently after recognizing the problem; but the brakes did not respond immediately due to the generator coming on line after engine start. Shortly thereafter; the brakes did respond resulting in an abrupt stop. There were no injuries or damage to airplane.

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Original NASA ASRS Text

Title: When pushback of the A320 was initiated without the tow bar securely attached to the tug; the aircraft rolled backwards without restraint and had to be braked abruptly to a halt by the flight crew.

Narrative: Our push back crew failed to secure the tow bar to the pushback vehicle; resulting in the aircraft being pushed back without control. I applied brakes gently after recognizing the problem; but the brakes did not respond immediately due to the generator coming on line after engine start. Shortly thereafter; the brakes did respond resulting in an abrupt stop. There were no injuries or damage to airplane.

Data retrieved from NASA's ASRS site as of July 2013 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.