Narrative:

I was in the captain seat; taxiing aircraft to a gate. Upon entering the apron of the gate; I called out for brake pressure and received a response that it was normal (3000 psi). I then proceeded to the gate and was guided by the guide person; who then gave me the stop signal. I stopped the aircraft and set the brakes; which I confirmed by the EICAS message 'parking brakes' and the parking brake light. I then started my shutdown procedure. During my shutdown procedure I noticed a bump to the aircraft and observed the parking brake had become disengaged. At no time was I aware of any aircraft movement.

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Original NASA ASRS Text

Title: Two mechanics repositioning a medium large jet to a gate failed to insure the parking brake was properly set and the aircraft rolled and impacted a jetway.

Narrative: I was in the captain seat; taxiing aircraft to a gate. Upon entering the apron of the gate; I called out for brake pressure and received a response that it was normal (3000 psi). I then proceeded to the gate and was guided by the guide person; who then gave me the stop signal. I stopped the aircraft and set the brakes; which I confirmed by the EICAS message 'parking brakes' and the parking brake light. I then started my shutdown procedure. During my shutdown procedure I noticed a bump to the aircraft and observed the parking brake had become disengaged. At no time was I aware of any aircraft movement.

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.