Narrative:

Situation started on the night of dec/wed/03. Aircraft arrived with write-up of, on taxi in flight control system message appeared. I was working #2 engine while another mechanic was troubleshooting per fim (flight information terminal) and mat (maintenance access terminal) on boeing 777. The mechanic, replaced the affected ace (actuator control electronics) computer no help. Old ace was reinstalled. The fault was the right outboard elevator actuator and the mat terminal was: bypass valve no response. The lead mechanic tried to order an elevator PCU (power control unit). The airline was not in stock on that part. The lead contacted the coordinator and they were going to rob the PCU off another aircraft. The lead mechanic and I talked to the coordinator again about the aircraft faulting the bypass solenoid valve on the PCU. He said yes on a B757 and a B767 it is a line replacement unit, but was not sure on the B777 and he would look for the documentation. The lead mechanic found the solenoid valve in the illustrated parts catalog manual for the effectivity of that aircraft. The part was delivered to the aircraft. Then turned aircraft over to first shift on morning of dec/thu/03. Coming back to work the night of dec/thu/03, the aircraft was again assigned to me. The WX was bad around 34 degrees F nd misty rain. The other shifts said they didn't think the solenoid valve could be changed without removing the elevator PCU. Also during the day, the coordinator involved the B777 analyst over the fleet of B777's and they looked over the component, maintenance manual and deciphered that it was a line replaceable unit. We decided it could be accessed and changed per the direction of my lead, coordinator and fleet analyst. The elevator power control unit did not need to be removed so we did not use that equipment. Hydraulics to tail isolated and breaker pulled per maintenance manual elevator PCU. After replacing solenoid valve on elevator PCU actuator, we put aircraft back to original confign per maintenance manual. To check out the PCU we turned on hydraulics for a leak check. The flight control system message cleared and leak check was good. Through mat terminal ran test on ace monitor check and ace confidence check both passed, they would not before. Solenoid valve signed off in logbook, and aircraft released by myself. 3 days later someone noticed the logbook entry which was reviewed by all parties involved, and said it cannot be changed without maintenance manual reference. Boeing contacted and said no to it, cannot be changed but they were thinking about letting us do it in the future. Now elevator PCU actuator being replaced on dec/xa/03.

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Original NASA ASRS Text

Title: A B777 ELEVATOR PWR UNIT SOLENOID VALVE WAS REPLACED WITH NO MAINT MANUAL REF. UNIT WAS NOT A LINE REPLACEABLE COMPONENT.

Narrative: SIT STARTED ON THE NIGHT OF DEC/WED/03. ACFT ARRIVED WITH WRITE-UP OF, ON TAXI IN FLT CTL SYS MESSAGE APPEARED. I WAS WORKING #2 ENG WHILE ANOTHER MECH WAS TROUBLESHOOTING PER FIM (FLT INFO TERMINAL) AND MAT (MAINT ACCESS TERMINAL) ON BOEING 777. THE MECH, REPLACED THE AFFECTED ACE (ACTUATOR CTL ELECTRONICS) COMPUTER NO HELP. OLD ACE WAS REINSTALLED. THE FAULT WAS THE R OUTBOARD ELEVATOR ACTUATOR AND THE MAT TERMINAL WAS: BYPASS VALVE NO RESPONSE. THE LEAD MECH TRIED TO ORDER AN ELEVATOR PCU (PWR CTL UNIT). THE AIRLINE WAS NOT IN STOCK ON THAT PART. THE LEAD CONTACTED THE COORDINATOR AND THEY WERE GOING TO ROB THE PCU OFF ANOTHER ACFT. THE LEAD MECH AND I TALKED TO THE COORDINATOR AGAIN ABOUT THE ACFT FAULTING THE BYPASS SOLENOID VALVE ON THE PCU. HE SAID YES ON A B757 AND A B767 IT IS A LINE REPLACEMENT UNIT, BUT WAS NOT SURE ON THE B777 AND HE WOULD LOOK FOR THE DOCUMENTATION. THE LEAD MECH FOUND THE SOLENOID VALVE IN THE ILLUSTRATED PARTS CATALOG MANUAL FOR THE EFFECTIVITY OF THAT ACFT. THE PART WAS DELIVERED TO THE ACFT. THEN TURNED ACFT OVER TO FIRST SHIFT ON MORNING OF DEC/THU/03. COMING BACK TO WORK THE NIGHT OF DEC/THU/03, THE ACFT WAS AGAIN ASSIGNED TO ME. THE WX WAS BAD AROUND 34 DEGS F ND MISTY RAIN. THE OTHER SHIFTS SAID THEY DIDN'T THINK THE SOLENOID VALVE COULD BE CHANGED WITHOUT REMOVING THE ELEVATOR PCU. ALSO DURING THE DAY, THE COORDINATOR INVOLVED THE B777 ANALYST OVER THE FLEET OF B777'S AND THEY LOOKED OVER THE COMPONENT, MAINT MANUAL AND DECIPHERED THAT IT WAS A LINE REPLACEABLE UNIT. WE DECIDED IT COULD BE ACCESSED AND CHANGED PER THE DIRECTION OF MY LEAD, COORDINATOR AND FLEET ANALYST. THE ELEVATOR PWR CTL UNIT DID NOT NEED TO BE REMOVED SO WE DID NOT USE THAT EQUIP. HYDS TO TAIL ISOLATED AND BREAKER PULLED PER MAINT MANUAL ELEVATOR PCU. AFTER REPLACING SOLENOID VALVE ON ELEVATOR PCU ACTUATOR, WE PUT ACFT BACK TO ORIGINAL CONFIGN PER MAINT MANUAL. TO CHK OUT THE PCU WE TURNED ON HYDS FOR A LEAK CHK. THE FLT CTL SYS MESSAGE CLRED AND LEAK CHK WAS GOOD. THROUGH MAT TERMINAL RAN TEST ON ACE MONITOR CHK AND ACE CONFIDENCE CHK BOTH PASSED, THEY WOULD NOT BEFORE. SOLENOID VALVE SIGNED OFF IN LOGBOOK, AND ACFT RELEASED BY MYSELF. 3 DAYS LATER SOMEONE NOTICED THE LOGBOOK ENTRY WHICH WAS REVIEWED BY ALL PARTIES INVOLVED, AND SAID IT CANNOT BE CHANGED WITHOUT MAINT MANUAL REF. BOEING CONTACTED AND SAID NO TO IT, CANNOT BE CHANGED BUT THEY WERE THINKING ABOUT LETTING US DO IT IN THE FUTURE. NOW ELEVATOR PCU ACTUATOR BEING REPLACED ON DEC/XA/03.

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.