Narrative:

We arrived at the gate a few minutes early. I followed the parking system; applied the brakes when indicated to do so and shut the engines down. I watched the marshaller holding the cross wands and continued to hold the brakes while waiting for the chocks in signal. During this time; out the corner of my eye; I noticed movement of the jetway and thought that was normal since we had just parked. Shortly thereafter; I realized that it was the aircraft that had begun to roll backwards and not the jetway. I thought I was applying adequate/constant pressure to the brakes to hold the aircraft; but obviously it started to roll and I hadn't realized it until we had rolled about 6 or 8 ft. I then aggressively applied the brakes and the aircraft stopped. I would like to blame this incident on the fact that it was a trying day in that the weather was lousy; the day was long; etc.; but this happened because I failed to hold adequate pressure on the brakes while waiting for the signal. Most of my flights during the past summer; I arrived at the gate with fairly hot brakes. Knowing that the parking brake should be released after the chocks are in so that the brakes can cool; I usually held the brakes (rather than setting the parking brake on) until the chocks in signal. In the future; I fully intend to set the parking brake and wait for the chocks signal before releasing the brakes.

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Original NASA ASRS Text

Title: An A330 Captain's personal preference to hold the brakes vice set the parking brake when given the stop signal by the marshaller results in the aircraft rolling backward when insufficient pressure was kept on the brake pedals.

Narrative: We arrived at the gate a few minutes early. I followed the parking system; applied the brakes when indicated to do so and shut the engines down. I watched the Marshaller holding the cross wands and continued to hold the brakes while waiting for the chocks in signal. During this time; out the corner of my eye; I noticed movement of the jetway and thought that was normal since we had just parked. Shortly thereafter; I realized that it was the aircraft that had begun to roll backwards and not the jetway. I thought I was applying adequate/constant pressure to the brakes to hold the aircraft; but obviously it started to roll and I hadn't realized it until we had rolled about 6 or 8 FT. I then aggressively applied the brakes and the aircraft stopped. I would like to blame this incident on the fact that it was a trying day in that the weather was lousy; the day was long; etc.; but this happened because I failed to hold adequate pressure on the brakes while waiting for the signal. Most of my flights during the past summer; I arrived at the gate with fairly hot brakes. Knowing that the parking brake should be released after the chocks are in so that the brakes can cool; I usually held the brakes (rather than setting the parking brake on) until the chocks in signal. In the future; I fully intend to set the parking brake and wait for the chocks signal before releasing the brakes.

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.