Narrative:

I ran over to help the tug driver disconnect aircraft X. I had him back up, I pulled the pin, then he drove away. About 2 seconds later, the aircraft started to roll back. I threw my flashlight under the nosewheels to try and stop the plane, with no luck. I then ran along the aircraft trying to find a pair of chocks or something to throw behind the tires, but nothing could be found. The aircraft proceeded to roll about 100 ft before it collided into the tail of aircraft Y. Supplemental information from acn 637541: I was sitting in the first pilot's seat. I set the brakes and a co-worker disconnected the tug from the aircraft. The aircraft started rolling. I reapplied the brakes, but nothing.

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Original NASA ASRS Text

Title: AN MD80 WAS TOWED TO THE HANGAR AND PARKED BUT NOT CHOCKED. TOWBAR REMOVED. WITHIN 2 SECONDS, AIRPLANE ROLLED BACK 100 FT, STRIKING AND DAMAGING ANOTHER PARKED AIRPLANE.

Narrative: I RAN OVER TO HELP THE TUG DRIVER DISCONNECT ACFT X. I HAD HIM BACK UP, I PULLED THE PIN, THEN HE DROVE AWAY. ABOUT 2 SECONDS LATER, THE ACFT STARTED TO ROLL BACK. I THREW MY FLASHLIGHT UNDER THE NOSEWHEELS TO TRY AND STOP THE PLANE, WITH NO LUCK. I THEN RAN ALONG THE ACFT TRYING TO FIND A PAIR OF CHOCKS OR SOMETHING TO THROW BEHIND THE TIRES, BUT NOTHING COULD BE FOUND. THE ACFT PROCEEDED TO ROLL ABOUT 100 FT BEFORE IT COLLIDED INTO THE TAIL OF ACFT Y. SUPPLEMENTAL INFO FROM ACN 637541: I WAS SITTING IN THE FIRST PLT'S SEAT. I SET THE BRAKES AND A CO-WORKER DISCONNECTED THE TUG FROM THE ACFT. THE ACFT STARTED ROLLING. I REAPPLIED THE BRAKES, BUT NOTHING.

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.