Narrative:

After completion of 'both engines shut down' checklist, I proceeded to walk back to rear of cabin. Approximately position was about row 2 or 3. F/a yelled 'we are moving.' I turned around and ran to cockpit to assure that brake was set. We were parked in rear of east lot facing swbnd between an small transport (to our left) and another light transport (to our right). The parking space available was rather restr, so that when we parked, the nose wheel was turned more than 30 degrees to the centerline of the aircraft when stopped. Found out later that parking spot that we were on had a very slight incline sloping to our rear. Wind direction was from 180 degrees at 8-10 KTS. Patches of slush and ice and pools of water covered east lot. Our position in relation to the 'T' parking spot when first stopped was slightly forward of the line and at an angle. Did not feel aircraft move--rolled back approximately 6-7'. Impacted a bus, striking one of buses left rear side windows with left lower rudder cover, penetrating bus window pane approximately 3-4'. In closing, may I state that to my best recollection, in regard to setting brakes, I definitely remember setting emergency wheel brake and standing on brake pedals and then releasing them before setting parking brake. No passenger were with us from yng (city we had just come from), and the bus driver was trying to come from behind us to pick us up to drive to terminal.

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Original NASA ASRS Text

Title: A PARKED COMMUTER LTT ROLLED BACKWARD, HITTING A CREW BUS POSITIONED BEHIND THE AFT.

Narrative: AFTER COMPLETION OF 'BOTH ENGS SHUT DOWN' CHKLIST, I PROCEEDED TO WALK BACK TO REAR OF CABIN. APPROX POS WAS ABOUT ROW 2 OR 3. F/A YELLED 'WE ARE MOVING.' I TURNED AROUND AND RAN TO COCKPIT TO ASSURE THAT BRAKE WAS SET. WE WERE PARKED IN REAR OF E LOT FACING SWBND BTWN AN SMT (TO OUR LEFT) AND ANOTHER LTT (TO OUR RIGHT). THE PARKING SPACE AVAILABLE WAS RATHER RESTR, SO THAT WHEN WE PARKED, THE NOSE WHEEL WAS TURNED MORE THAN 30 DEGS TO THE CENTERLINE OF THE ACFT WHEN STOPPED. FOUND OUT LATER THAT PARKING SPOT THAT WE WERE ON HAD A VERY SLIGHT INCLINE SLOPING TO OUR REAR. WIND DIRECTION WAS FROM 180 DEGS AT 8-10 KTS. PATCHES OF SLUSH AND ICE AND POOLS OF WATER COVERED E LOT. OUR POS IN RELATION TO THE 'T' PARKING SPOT WHEN FIRST STOPPED WAS SLIGHTLY FORWARD OF THE LINE AND AT AN ANGLE. DID NOT FEEL ACFT MOVE--ROLLED BACK APPROX 6-7'. IMPACTED A BUS, STRIKING ONE OF BUSES LEFT REAR SIDE WINDOWS WITH LEFT LOWER RUDDER COVER, PENETRATING BUS WINDOW PANE APPROX 3-4'. IN CLOSING, MAY I STATE THAT TO MY BEST RECOLLECTION, IN REGARD TO SETTING BRAKES, I DEFINITELY REMEMBER SETTING EMER WHEEL BRAKE AND STANDING ON BRAKE PEDALS AND THEN RELEASING THEM BEFORE SETTING PARKING BRAKE. NO PAX WERE WITH US FROM YNG (CITY WE HAD JUST COME FROM), AND THE BUS DRIVER WAS TRYING TO COME FROM BEHIND US TO PICK US UP TO DRIVE TO TERMINAL.

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.