Narrative:

The problem arose at our repair station when 2 popped fuel filter bypass indicators were discovered on a preflight of a 4 engine aircraft. The customer elected to not accomplish the required maintenance actions, to include replacing the fuel filters. The customer instructed to reset the indicators and install the cowlings so he could continue his flight schedule. The bypass condition was noted as an item on the aircraft's work order. The mechanic that reset the indicators and installed the cowlings signed off the item as technician. The condition and safety of the installations of the cowlings were examined by an inspector who signed off the inspection portion of the item. The corrective action section reflected only the actions performed. The customer was aware that we did not regard the aircraft as airworthy in this condition. The customer was aware that the extent of our actions provided no resolution to the problem and that to continue operation could only, at best be regarded as a 'troubleshooting in progress -- test flight.' technical support has in the past advised our maintenance team to reset, run and test fly aircraft to eliminate the possibility of a transient bypass indication as a result of external forces (hard landing, weak indicator latching mechanism, etc), to rechk the indicators at the end of the next flight leg and at that time to replace filters or investigate further if necessary as indicated by a recurrence of the bypass condition. The employment of this practice has been recommended by technical support as a result of large numbers of reports of false indications resulting from faulty bypass indicator assemblies, hard landing impacts and other external causes. We did not intend to make an airworthiness statement at all in regards to the 'popped bypass indicator' discrepancy and the operator/customer was aware of the condition of the aircraft. We were aware that no airworthy condition had been established by the extent of our actions in this instance. No logbook/permanent record entry was made and no specific return to service approval was intended to be generated to indicate that this system's problem had been rectified. It was not our intent to imply airworthiness or in any other way state that the aircraft was approved for return to service for this discrepant item. In an oversight, we mistakenly neglected to omit the item's number from the closing signoff for the work order itself on its cover. The fact that the item had not been resolved was overlooked in part by the presence of a technician and an inspector signoff and thereby inadvertently included in the work order closing signoff. The customer acquired a copy of the repair station's work order and later advised us that we had approved the item for return to service. We advised the customer that this was an error. We have reviewed our approval for return to service procedures and have been emphasizing the importance of detailed and complete review of all item's status prior to the final signing off of the airworthiness statement for the work order's items at closing.

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Original NASA ASRS Text

Title: A LOCKHEED JETSTAR WAS FOUND TO HAVE 2 FUEL FILTER BYPASS INDICATORS TRIPPED. CUSTOMER REQUESTED RESET OF INDICATORS. INDICATORS RESET AND INADVERTENTLY SIGNED OFF AS OK FOR SVC.

Narrative: THE PROB AROSE AT OUR REPAIR STATION WHEN 2 POPPED FUEL FILTER BYPASS INDICATORS WERE DISCOVERED ON A PREFLT OF A 4 ENG ACFT. THE CUSTOMER ELECTED TO NOT ACCOMPLISH THE REQUIRED MAINT ACTIONS, TO INCLUDE REPLACING THE FUEL FILTERS. THE CUSTOMER INSTRUCTED TO RESET THE INDICATORS AND INSTALL THE COWLINGS SO HE COULD CONTINUE HIS FLT SCHEDULE. THE BYPASS CONDITION WAS NOTED AS AN ITEM ON THE ACFT'S WORK ORDER. THE MECH THAT RESET THE INDICATORS AND INSTALLED THE COWLINGS SIGNED OFF THE ITEM AS TECHNICIAN. THE CONDITION AND SAFETY OF THE INSTALLATIONS OF THE COWLINGS WERE EXAMINED BY AN INSPECTOR WHO SIGNED OFF THE INSPECTION PORTION OF THE ITEM. THE CORRECTIVE ACTION SECTION REFLECTED ONLY THE ACTIONS PERFORMED. THE CUSTOMER WAS AWARE THAT WE DID NOT REGARD THE ACFT AS AIRWORTHY IN THIS CONDITION. THE CUSTOMER WAS AWARE THAT THE EXTENT OF OUR ACTIONS PROVIDED NO RESOLUTION TO THE PROB AND THAT TO CONTINUE OP COULD ONLY, AT BEST BE REGARDED AS A 'TROUBLESHOOTING IN PROGRESS -- TEST FLT.' TECHNICAL SUPPORT HAS IN THE PAST ADVISED OUR MAINT TEAM TO RESET, RUN AND TEST FLY ACFT TO ELIMINATE THE POSSIBILITY OF A TRANSIENT BYPASS INDICATION AS A RESULT OF EXTERNAL FORCES (HARD LNDG, WEAK INDICATOR LATCHING MECHANISM, ETC), TO RECHK THE INDICATORS AT THE END OF THE NEXT FLT LEG AND AT THAT TIME TO REPLACE FILTERS OR INVESTIGATE FURTHER IF NECESSARY AS INDICATED BY A RECURRENCE OF THE BYPASS CONDITION. THE EMPLOYMENT OF THIS PRACTICE HAS BEEN RECOMMENDED BY TECHNICAL SUPPORT AS A RESULT OF LARGE NUMBERS OF RPTS OF FALSE INDICATIONS RESULTING FROM FAULTY BYPASS INDICATOR ASSEMBLIES, HARD LNDG IMPACTS AND OTHER EXTERNAL CAUSES. WE DID NOT INTEND TO MAKE AN AIRWORTHINESS STATEMENT AT ALL IN REGARDS TO THE 'POPPED BYPASS INDICATOR' DISCREPANCY AND THE OPERATOR/CUSTOMER WAS AWARE OF THE CONDITION OF THE ACFT. WE WERE AWARE THAT NO AIRWORTHY CONDITION HAD BEEN ESTABLISHED BY THE EXTENT OF OUR ACTIONS IN THIS INSTANCE. NO LOGBOOK/PERMANENT RECORD ENTRY WAS MADE AND NO SPECIFIC RETURN TO SVC APPROVAL WAS INTENDED TO BE GENERATED TO INDICATE THAT THIS SYS'S PROB HAD BEEN RECTIFIED. IT WAS NOT OUR INTENT TO IMPLY AIRWORTHINESS OR IN ANY OTHER WAY STATE THAT THE ACFT WAS APPROVED FOR RETURN TO SVC FOR THIS DISCREPANT ITEM. IN AN OVERSIGHT, WE MISTAKENLY NEGLECTED TO OMIT THE ITEM'S NUMBER FROM THE CLOSING SIGNOFF FOR THE WORK ORDER ITSELF ON ITS COVER. THE FACT THAT THE ITEM HAD NOT BEEN RESOLVED WAS OVERLOOKED IN PART BY THE PRESENCE OF A TECHNICIAN AND AN INSPECTOR SIGNOFF AND THEREBY INADVERTENTLY INCLUDED IN THE WORK ORDER CLOSING SIGNOFF. THE CUSTOMER ACQUIRED A COPY OF THE REPAIR STATION'S WORK ORDER AND LATER ADVISED US THAT WE HAD APPROVED THE ITEM FOR RETURN TO SVC. WE ADVISED THE CUSTOMER THAT THIS WAS AN ERROR. WE HAVE REVIEWED OUR APPROVAL FOR RETURN TO SVC PROCS AND HAVE BEEN EMPHASIZING THE IMPORTANCE OF DETAILED AND COMPLETE REVIEW OF ALL ITEM'S STATUS PRIOR TO THE FINAL SIGNING OFF OF THE AIRWORTHINESS STATEMENT FOR THE WORK ORDER'S ITEMS AT CLOSING.

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.