Narrative:

Myself and another mechanic were given a card to remove #1 brake (normal brake servo valve). The aircraft was having a #2 engine pneumatic duct removed off the #2 engine pylon; and the engine had to be removed for this procedure. So there was no electrical power to aircraft. We used the reference maintenance MEL XXX to remove and install the valve. It was getting to the end of the shift so we did not get a chance to do a leak and operation check of the valve; so we wrote a card to have this procedure accomplished after they put the power back on the aircraft. In the steps it called out to bleed the brake to the servo valve which was being replaced; and leak check the servo valve itself and an operations check. The reason I am writing this is because after I came back to work after my day off; I was told that there was an incident that had something to do with the procedure we did on the replacement of the (normal brake servo valve). We signed off the write-up and generated another write-up. Maybe if I had given the next shift who were taking over where we left off a verbal debriefing pass down on what else needed to be accomplished; there might not been any misunderstanding as to what was needed to accomplish the rest of the job task. Also what I should have done was write a card against the installation of the valve and referenced it to the deferred item. Callback conversation with reporter revealed the following information: the #1 normal brake servo valve was replaced after previous brake changes did not correct the hot; sticky brake condition. He made write-ups to do a leak and operations check of the servo valve installation due to shift change. On taxi out to the terminal from the hangar; the same sticky; hot brakes condition re-appeared. Maintenance was trying to determine who was involved with the servo valve installation. Reporter also stated perhaps if he had made another write-up specifically for mechanics to perform a brake taxi check prior to releasing aircraft to terminal might have helped in finding out the earlier condition still existed.

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Original NASA ASRS Text

Title: AN AIRBUS A-320 ACFT #1 BRAKE (NORMAL BRAKE SERVO VALVE) WAS REPLACED DUE TO PREVIOUS BRAKE CHANGES NO HELP FOR HOT; STICKY BRAKES CONDITION.

Narrative: MYSELF AND ANOTHER MECH WERE GIVEN A CARD TO REMOVE #1 BRAKE (NORMAL BRAKE SERVO VALVE). THE ACFT WAS HAVING A #2 ENG PNEUMATIC DUCT REMOVED OFF THE #2 ENG PYLON; AND THE ENG HAD TO BE REMOVED FOR THIS PROC. SO THERE WAS NO ELECTRICAL PWR TO ACFT. WE USED THE REF MAINT MEL XXX TO REMOVE AND INSTALL THE VALVE. IT WAS GETTING TO THE END OF THE SHIFT SO WE DID NOT GET A CHANCE TO DO A LEAK AND OP CHK OF THE VALVE; SO WE WROTE A CARD TO HAVE THIS PROC ACCOMPLISHED AFTER THEY PUT THE PWR BACK ON THE ACFT. IN THE STEPS IT CALLED OUT TO BLEED THE BRAKE TO THE SERVO VALVE WHICH WAS BEING REPLACED; AND LEAK CHK THE SERVO VALVE ITSELF AND AN OPS CHK. THE REASON I AM WRITING THIS IS BECAUSE AFTER I CAME BACK TO WORK AFTER MY DAY OFF; I WAS TOLD THAT THERE WAS AN INCIDENT THAT HAD SOMETHING TO DO WITH THE PROC WE DID ON THE REPLACEMENT OF THE (NORMAL BRAKE SERVO VALVE). WE SIGNED OFF THE WRITE-UP AND GENERATED ANOTHER WRITE-UP. MAYBE IF I HAD GIVEN THE NEXT SHIFT WHO WERE TAKING OVER WHERE WE LEFT OFF A VERBAL DEBRIEFING PASS DOWN ON WHAT ELSE NEEDED TO BE ACCOMPLISHED; THERE MIGHT NOT BEEN ANY MISUNDERSTANDING AS TO WHAT WAS NEEDED TO ACCOMPLISH THE REST OF THE JOB TASK. ALSO WHAT I SHOULD HAVE DONE WAS WRITE A CARD AGAINST THE INSTALLATION OF THE VALVE AND REFED IT TO THE DEFERRED ITEM. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE #1 NORMAL BRAKE SERVO VALVE WAS REPLACED AFTER PREVIOUS BRAKE CHANGES DID NOT CORRECT THE HOT; STICKY BRAKE CONDITION. HE MADE WRITE-UPS TO DO A LEAK AND OPERATIONS CHECK OF THE SERVO VALVE INSTALLATION DUE TO SHIFT CHANGE. ON TAXI OUT TO THE TERMINAL FROM THE HANGAR; THE SAME STICKY; HOT BRAKES CONDITION RE-APPEARED. MAINT WAS TRYING TO DETERMINE WHO WAS INVOLVED WITH THE SERVO VALVE INSTALLATION. REPORTER ALSO STATED PERHAPS IF HE HAD MADE ANOTHER WRITE-UP SPECIFICALLY FOR MECHANICS TO PERFORM A BRAKE TAXI CHECK PRIOR TO RELEASING ACFT TO TERMINAL MIGHT HAVE HELPED IN FINDING OUT THE EARLIER CONDITION STILL EXISTED.

Data retrieved from NASA's ASRS site as of January 2009 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.