Narrative:

After parking at the gate in las, we requested, via the operations radio frequency, to have the wheels chocked so that we could release the parking brake for brake cooling. The scheduled turn time was 45 mins. Las operations asked us to stand by on the frequency for clearance to release the parking brake. A few mins later, operations verified that the main wheels were chocked and cleared us to release the brakes. About 15 mins prior to departure time for flight to sfo, I queried operations about when we should set the parking brake in preparation for departure. Operations responded that they would contact us over the frequency or that the push crew would contact via the headset and tell us when he set the brakes in preparation for pushback. Just after the cabin door was closed and prior to any communication from the push crew or operations personnel, we heard a thumping sound coming from the nose gear. Suspicious that someone might be pulling the chocks, I watched for any aircraft movement. After several thuds from the nosewheel, the aircraft began to roll backward slightly and I immediately set the parking brake. I don't believe the aircraft moved more than a ft before we stopped it, and I think the tug was connected. I asked operations if someone had just pulled the chocks, and they responded that the ramp had pulled the chocks. I informed operations that pulling the chocks had not been coordinated or communicated to the flight deck and we were not ready for the ramp to do that because we had not set the brake yet. I asked operations to talk to the ramp personnel about this. Although very little aircraft movement occurred during this incident, the potential for damage and injury is obvious if the aircraft is allowed to move without the crew being ready, whether or not the tug is hooked up. I could not find any guidance in the A320 flight manual for releasing the parking brake to allow for cooling during a quick turn. The fom addresses parking brakes. This paragraph states: 'once the receipt complete signal has been received, do not release the brakes without direct contact with the guideman.' in las, the release of the parking brake for cooling was coordinated through operations via the operations frequency. It is my opinion, that direct contact with a guideman for brake release is a safer procedure because the guideman can more closely monitor for aircraft movement. This would also be more in compliance with current fom language. As for when to reset the parking brake before departure, which has to happen in order to sequence the ACARS out report, there is no guidance. It is my opinion that this should also be coordinated directly between the flight deck and the guideman before the chocks are removed.

Related reports:

Google
 

Original NASA ASRS Text

Title: A320 CREW ROLLED BACK AFTER THE CHOCKS WERE REMOVED AND THE PARKING BRAKES WERE NOT SET.

Narrative: AFTER PARKING AT THE GATE IN LAS, WE REQUESTED, VIA THE OPS RADIO FREQ, TO HAVE THE WHEELS CHOCKED SO THAT WE COULD RELEASE THE PARKING BRAKE FOR BRAKE COOLING. THE SCHEDULED TURN TIME WAS 45 MINS. LAS OPS ASKED US TO STAND BY ON THE FREQ FOR CLRNC TO RELEASE THE PARKING BRAKE. A FEW MINS LATER, OPS VERIFIED THAT THE MAIN WHEELS WERE CHOCKED AND CLRED US TO RELEASE THE BRAKES. ABOUT 15 MINS PRIOR TO DEP TIME FOR FLT TO SFO, I QUERIED OPS ABOUT WHEN WE SHOULD SET THE PARKING BRAKE IN PREPARATION FOR DEP. OPS RESPONDED THAT THEY WOULD CONTACT US OVER THE FREQ OR THAT THE PUSH CREW WOULD CONTACT VIA THE HEADSET AND TELL US WHEN HE SET THE BRAKES IN PREPARATION FOR PUSHBACK. JUST AFTER THE CABIN DOOR WAS CLOSED AND PRIOR TO ANY COM FROM THE PUSH CREW OR OPS PERSONNEL, WE HEARD A THUMPING SOUND COMING FROM THE NOSE GEAR. SUSPICIOUS THAT SOMEONE MIGHT BE PULLING THE CHOCKS, I WATCHED FOR ANY ACFT MOVEMENT. AFTER SEVERAL THUDS FROM THE NOSEWHEEL, THE ACFT BEGAN TO ROLL BACKWARD SLIGHTLY AND I IMMEDIATELY SET THE PARKING BRAKE. I DON'T BELIEVE THE ACFT MOVED MORE THAN A FT BEFORE WE STOPPED IT, AND I THINK THE TUG WAS CONNECTED. I ASKED OPS IF SOMEONE HAD JUST PULLED THE CHOCKS, AND THEY RESPONDED THAT THE RAMP HAD PULLED THE CHOCKS. I INFORMED OPS THAT PULLING THE CHOCKS HAD NOT BEEN COORDINATED OR COMMUNICATED TO THE FLT DECK AND WE WERE NOT READY FOR THE RAMP TO DO THAT BECAUSE WE HAD NOT SET THE BRAKE YET. I ASKED OPS TO TALK TO THE RAMP PERSONNEL ABOUT THIS. ALTHOUGH VERY LITTLE ACFT MOVEMENT OCCURRED DURING THIS INCIDENT, THE POTENTIAL FOR DAMAGE AND INJURY IS OBVIOUS IF THE ACFT IS ALLOWED TO MOVE WITHOUT THE CREW BEING READY, WHETHER OR NOT THE TUG IS HOOKED UP. I COULD NOT FIND ANY GUIDANCE IN THE A320 FLT MANUAL FOR RELEASING THE PARKING BRAKE TO ALLOW FOR COOLING DURING A QUICK TURN. THE FOM ADDRESSES PARKING BRAKES. THIS PARAGRAPH STATES: 'ONCE THE RECEIPT COMPLETE SIGNAL HAS BEEN RECEIVED, DO NOT RELEASE THE BRAKES WITHOUT DIRECT CONTACT WITH THE GUIDEMAN.' IN LAS, THE RELEASE OF THE PARKING BRAKE FOR COOLING WAS COORDINATED THROUGH OPS VIA THE OPS FREQ. IT IS MY OPINION, THAT DIRECT CONTACT WITH A GUIDEMAN FOR BRAKE RELEASE IS A SAFER PROC BECAUSE THE GUIDEMAN CAN MORE CLOSELY MONITOR FOR ACFT MOVEMENT. THIS WOULD ALSO BE MORE IN COMPLIANCE WITH CURRENT FOM LANGUAGE. AS FOR WHEN TO RESET THE PARKING BRAKE BEFORE DEP, WHICH HAS TO HAPPEN IN ORDER TO SEQUENCE THE ACARS OUT RPT, THERE IS NO GUIDANCE. IT IS MY OPINION THAT THIS SHOULD ALSO BE COORDINATED DIRECTLY BTWN THE FLT DECK AND THE GUIDEMAN BEFORE THE CHOCKS ARE REMOVED.

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.