Narrative:

I picked up aircraft X with 2 other mechanics at the gate and brought it to the hangar, parked it at X position, chocked it, disconnected tow bar, moved entry stand to aircraft, performed my part of the check (APU, cargo and tire and brakes). Finished check at approximately XA30 apr/wed/02. We'd left aircraft (had been decatered, had not been cleaned by cabin service). Avionics was still on aircraft when I left. Moved another aircraft at XC30 from hangar to gate. Punched out at about XD30 apr/wed/02 and was told that aircraft rolled at XE50. Another aircraft rolled off X position before. To correct this problem, suggest all gear be choclked in the future and will ask management to provide chocks if asked. Callback conversation with reporter revealed the following information: the reporter stated the airplane was picked up and towed to the hangar line and chocked per the parking procedures with the parking brake applied. The reporter said the 'a' check was accomplished with only the avionics people still working on the airplane and cabin cleaning not done. The reporter stated the shift punched out. Slightly over 1 hour 15 mins later, the airplane rolled. The reporter said this was the second incident of an aircraft rolling off this parking spot. The reporter stated it is a known fact the parking brake pressure bled off, but if the chocks were not disturbed, or removed, the airplane should not have moved.

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Original NASA ASRS Text

Title: A B767-300 ACFT PARKED ON HANGAR LINE SPOT, ROLLED FORWARD INTO A PUBLIC STREET, INCURRING MINOR DAMAGE. CAUSE STILL UNDER INVESTIGATION.

Narrative: I PICKED UP ACFT X WITH 2 OTHER MECHS AT THE GATE AND BROUGHT IT TO THE HANGAR, PARKED IT AT X POS, CHOCKED IT, DISCONNECTED TOW BAR, MOVED ENTRY STAND TO ACFT, PERFORMED MY PART OF THE CHK (APU, CARGO AND TIRE AND BRAKES). FINISHED CHK AT APPROX XA30 APR/WED/02. WE'D LEFT ACFT (HAD BEEN DECATERED, HAD NOT BEEN CLEANED BY CABIN SVC). AVIONICS WAS STILL ON ACFT WHEN I LEFT. MOVED ANOTHER ACFT AT XC30 FROM HANGAR TO GATE. PUNCHED OUT AT ABOUT XD30 APR/WED/02 AND WAS TOLD THAT ACFT ROLLED AT XE50. ANOTHER ACFT ROLLED OFF X POS BEFORE. TO CORRECT THIS PROB, SUGGEST ALL GEAR BE CHOCLKED IN THE FUTURE AND WILL ASK MGMNT TO PROVIDE CHOCKS IF ASKED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE AIRPLANE WAS PICKED UP AND TOWED TO THE HANGAR LINE AND CHOCKED PER THE PARKING PROCS WITH THE PARKING BRAKE APPLIED. THE RPTR SAID THE 'A' CHK WAS ACCOMPLISHED WITH ONLY THE AVIONICS PEOPLE STILL WORKING ON THE AIRPLANE AND CABIN CLEANING NOT DONE. THE RPTR STATED THE SHIFT PUNCHED OUT. SLIGHTLY OVER 1 HR 15 MINS LATER, THE AIRPLANE ROLLED. THE RPTR SAID THIS WAS THE SECOND INCIDENT OF AN ACFT ROLLING OFF THIS PARKING SPOT. THE RPTR STATED IT IS A KNOWN FACT THE PARKING BRAKE PRESSURE BLED OFF, BUT IF THE CHOCKS WERE NOT DISTURBED, OR REMOVED, THE AIRPLANE SHOULD NOT HAVE MOVED.

Data retrieved from NASA's ASRS site as of July 2007 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.