Narrative:

Engineering order WX-xx was issued to aircraft xyz for activation of cargo compartment fire suppression system. During the functional check it was discovered that a step[ was missing, to reset a smoke detector panel circuit breaker so warning lights would function properly on subsequent steps (air carrier fire protection system installation instruction 8.7.19 and 8.7.20 dated 1/xa/01 step 'I' was missing). Maintenance and inspection personnel continued with test procedure, which was completed with no other discrepancies. At completion of the procedure, a decision was made by personnel doing the test, not to sign off the functional check due to the missing step XA00 jan/mon/01. Since the system had not been activated, I was asked and agreed to place the engineering order on a maintenance carryover for activation after the procedure was corrected. I learned at this time that 6 other aircraft had been activated with the same procedure. The missing step was known and considered a minor omission. The fire suppression system was installed under an supplemental type certificate, so our engineering department would have to go back to the supplemental type certificate holder for a procedure correction, which would take at least 1 day. The aircraft was required for revenue service at XC30 that morning. After reviewing engineering order WX-xx, the avionics lead and myself initiated carryover zgy at XB30 jan/mon/01 (log entry P. Abc). Fire suppression system circuit breakers were pulled and collared (engineering order section III step 2). Maintenance control was notified. We noted that MEL 26-10 did not require pulling any breakers but intent was to deactivate the system so pulling breakers was seen as a necessary step to isolate fire suppression from the electrical system. Aircraft xyz was released for service at XC30. At XG30 local time, the aircraft flight crew made a log entry (P. XYZ0 stating 'master warning light comes on when switching electrical busses.' engineering was called and determined this was correct operation when fire suppression circuit breakers were pulled. System is designed to alert the flight crew in this manner if it is not operational. Revised functional check procedure was received from air carrier by facsimile at XF07 local time jan/mon/01. Step 'I' was added as requested. No other corrections were indicated, revision number stayed the same (air carrier fire protection system installation instructions WX-xx). Aircraft xyz was scheduled to remain overnight in milwaukee that evening but went to an outstation due to routing change. Aircraft xyz did remain overnight in milwaukee on jan/tue/01. Fire suppression system functional check was completed with no discrepancies. Carryover zgy cleared (log page abc). Human performance considerations: prior to this incident, I was not familiar with the fire suppression system, as it was a new installation for the fleet. This was the first activation I was present for. With 6 other aircraft fire suppression system activated using the same procedure, I was sure aircraft xyz was working properly and with a minor paperwork correction the carryover could be cleared. To prevent a recurrence of this type incident in the future, I will not allow modification work to be carried over once it is stated. The entire modification will have to be completed and pass the appropriate functional check with no discrepancies before return to service.

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Original NASA ASRS Text

Title: AN ACFT WAS RELEASED FOR SVC IN NON COMPLIANCE WITH AN INCOMPLETE INSTALLATION OF THE CARGO PIT FIRE PROTECTION SYS USING THE MEL FOR AUTH.

Narrative: ENGINEERING ORDER WX-XX WAS ISSUED TO ACFT XYZ FOR ACTIVATION OF CARGO COMPARTMENT FIRE SUPPRESSION SYS. DURING THE FUNCTIONAL CHK IT WAS DISCOVERED THAT A STEP[ WAS MISSING, TO RESET A SMOKE DETECTOR PANEL CIRCUIT BREAKER SO WARNING LIGHTS WOULD FUNCTION PROPERLY ON SUBSEQUENT STEPS (ACR FIRE PROTECTION SYS INSTALLATION INSTRUCTION 8.7.19 AND 8.7.20 DATED 1/XA/01 STEP 'I' WAS MISSING). MAINT AND INSPECTION PERSONNEL CONTINUED WITH TEST PROC, WHICH WAS COMPLETED WITH NO OTHER DISCREPANCIES. AT COMPLETION OF THE PROC, A DECISION WAS MADE BY PERSONNEL DOING THE TEST, NOT TO SIGN OFF THE FUNCTIONAL CHK DUE TO THE MISSING STEP XA00 JAN/MON/01. SINCE THE SYS HAD NOT BEEN ACTIVATED, I WAS ASKED AND AGREED TO PLACE THE ENGINEERING ORDER ON A MAINT CARRYOVER FOR ACTIVATION AFTER THE PROC WAS CORRECTED. I LEARNED AT THIS TIME THAT 6 OTHER ACFT HAD BEEN ACTIVATED WITH THE SAME PROC. THE MISSING STEP WAS KNOWN AND CONSIDERED A MINOR OMISSION. THE FIRE SUPPRESSION SYS WAS INSTALLED UNDER AN SUPPLEMENTAL TYPE CERTIFICATE, SO OUR ENGINEERING DEPT WOULD HAVE TO GO BACK TO THE SUPPLEMENTAL TYPE CERTIFICATE HOLDER FOR A PROC CORRECTION, WHICH WOULD TAKE AT LEAST 1 DAY. THE ACFT WAS REQUIRED FOR REVENUE SVC AT XC30 THAT MORNING. AFTER REVIEWING ENGINEERING ORDER WX-XX, THE AVIONICS LEAD AND MYSELF INITIATED CARRYOVER ZGY AT XB30 JAN/MON/01 (LOG ENTRY P. ABC). FIRE SUPPRESSION SYS CIRCUIT BREAKERS WERE PULLED AND COLLARED (ENGINEERING ORDER SECTION III STEP 2). MAINT CTL WAS NOTIFIED. WE NOTED THAT MEL 26-10 DID NOT REQUIRE PULLING ANY BREAKERS BUT INTENT WAS TO DEACTIVATE THE SYS SO PULLING BREAKERS WAS SEEN AS A NECESSARY STEP TO ISOLATE FIRE SUPPRESSION FROM THE ELECTRICAL SYS. ACFT XYZ WAS RELEASED FOR SVC AT XC30. AT XG30 LCL TIME, THE ACFT FLC MADE A LOG ENTRY (P. XYZ0 STATING 'MASTER WARNING LIGHT COMES ON WHEN SWITCHING ELECTRICAL BUSSES.' ENGINEERING WAS CALLED AND DETERMINED THIS WAS CORRECT OP WHEN FIRE SUPPRESSION CIRCUIT BREAKERS WERE PULLED. SYS IS DESIGNED TO ALERT THE FLC IN THIS MANNER IF IT IS NOT OPERATIONAL. REVISED FUNCTIONAL CHK PROC WAS RECEIVED FROM ACR BY FAX AT XF07 LCL TIME JAN/MON/01. STEP 'I' WAS ADDED AS REQUESTED. NO OTHER CORRECTIONS WERE INDICATED, REVISION NUMBER STAYED THE SAME (ACR FIRE PROTECTION SYS INSTALLATION INSTRUCTIONS WX-XX). ACFT XYZ WAS SCHEDULED TO REMAIN OVERNIGHT IN MILWAUKEE THAT EVENING BUT WENT TO AN OUTSTATION DUE TO ROUTING CHANGE. ACFT XYZ DID REMAIN OVERNIGHT IN MILWAUKEE ON JAN/TUE/01. FIRE SUPPRESSION SYS FUNCTIONAL CHK WAS COMPLETED WITH NO DISCREPANCIES. CARRYOVER ZGY CLRED (LOG PAGE ABC). HUMAN PERFORMANCE CONSIDERATIONS: PRIOR TO THIS INCIDENT, I WAS NOT FAMILIAR WITH THE FIRE SUPPRESSION SYS, AS IT WAS A NEW INSTALLATION FOR THE FLEET. THIS WAS THE FIRST ACTIVATION I WAS PRESENT FOR. WITH 6 OTHER ACFT FIRE SUPPRESSION SYS ACTIVATED USING THE SAME PROC, I WAS SURE ACFT XYZ WAS WORKING PROPERLY AND WITH A MINOR PAPERWORK CORRECTION THE CARRYOVER COULD BE CLRED. TO PREVENT A RECURRENCE OF THIS TYPE INCIDENT IN THE FUTURE, I WILL NOT ALLOW MODIFICATION WORK TO BE CARRIED OVER ONCE IT IS STATED. THE ENTIRE MODIFICATION WILL HAVE TO BE COMPLETED AND PASS THE APPROPRIATE FUNCTIONAL CHK WITH NO DISCREPANCIES BEFORE RETURN TO SVC.

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.