Narrative:

We came into the parking space normally. While I was running the engine shutdown checklist, the aircraft started moving. The ground crew tapped the side of the airplane under the cockpit, which caused us (the crew) to look outside and we realized we were slowly rolling back. We rolled about 3 ft before the captain got the brake on. I don't know if the parking brake was ever set when I called for it or not, but the captain did reply 'set.' captain thought he probably didn't set the parking brake correctly and it popped off. I don't think I checked for the red parking brake light to back up the captain, but from now on I sure will. No one was hurt, no damage was done, except to the captain's ego. I thought the light may have been on, but not sure.

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Original NASA ASRS Text

Title: A B727 FREIGHTER STARTS TO ROLL BACK ON THE RAMP WHEN THE CAPT FAILS TO SET THE PARKING BRAKE CORRECTLY AFTER PARKED AT MKE, WI.

Narrative: WE CAME INTO THE PARKING SPACE NORMALLY. WHILE I WAS RUNNING THE ENG SHUTDOWN CHKLIST, THE ACFT STARTED MOVING. THE GND CREW TAPPED THE SIDE OF THE AIRPLANE UNDER THE COCKPIT, WHICH CAUSED US (THE CREW) TO LOOK OUTSIDE AND WE REALIZED WE WERE SLOWLY ROLLING BACK. WE ROLLED ABOUT 3 FT BEFORE THE CAPT GOT THE BRAKE ON. I DON'T KNOW IF THE PARKING BRAKE WAS EVER SET WHEN I CALLED FOR IT OR NOT, BUT THE CAPT DID REPLY 'SET.' CAPT THOUGHT HE PROBABLY DIDN'T SET THE PARKING BRAKE CORRECTLY AND IT POPPED OFF. I DON'T THINK I CHKED FOR THE RED PARKING BRAKE LIGHT TO BACK UP THE CAPT, BUT FROM NOW ON I SURE WILL. NO ONE WAS HURT, NO DAMAGE WAS DONE, EXCEPT TO THE CAPT'S EGO. I THOUGHT THE LIGHT MAY HAVE BEEN ON, BUT NOT SURE.

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.