Narrative:

I work as a system aircraft maintenance controller (sam) in san francisco, ca, and routinely provide assistance to flcs as problems develop with aircraft in-flight or on the ground. I was involved in a situation that resulted in a condition which affected the ground operational performance of an medium large transport a aircraft on landing at seattle on flight XXX, may/xx/93. The aircraft landed and reported the #2 engine reverser did not deploy on landing. (For informational purposes, the #1 engine reverser system had been deferred inoperative on may/xx/93 at msy and should have been deactivated per special procedure). I had received a radio call from flight after departure at denver. The crew reported they had an 'engine' light on the forward panel 6 pack annunciator module when the recall check was done. No other engine associated faults were observed or reported. This light could have been caused by an engine reverser fault condition. When I reviewed the aircraft current deferred items, I saw that the #1 engine reverser was inoperative. I asked the crew to check and see if the engine reverser control circuit breaker was pulled on the panel as required by the inoperative reverser procedure. The crew advised that no circuit breakers were found out. To comply, I advised the crew to pull the engine control circuit breaker at grid location C-6. I had determined this circuit breaker location using the medium large transport quick reference circuit breaker diagram for an medium large transport B aircraft. I assumed that this was the correct circuit breaker for the #1 engine reverser control system. The circuit breaker is not idented by engine position and being located on the left side of the panel as viewed, one might assume that it would be for the left or #1 engine. The crew did not report any further problems with the 'engine' light so I thought the situation had been corrected. I then contacted seattle maintenance and requested that they check the aircraft on arrival and confirm that reverser deactivation procedures had been complied with. Seattle maintenance found that the #1 engine reverser control circuit breaker had not been pulled as specified. The #2 reverser circuit breaker, however, was found out and was the reason that the #2 reverser did not deploy on landing. In the future I plan to exercise more caution when researching and advising circuit breaker locations and hope this situation will not recur. I feel, however, that flcs have some responsibility in this type of a situation to challenge and confirm these actions as well as be aware of the maintenance status of their aircraft.

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Original NASA ASRS Text

Title: FLC OF MLG ACR ACFT INADVERTENTLY DEACTIVATED THE REMAINING ENG REVERSER AFTER FOLLOWING INSTRUCTIONS FROM THE COMPANY MAINT CTLR.

Narrative: I WORK AS A SYS ACFT MAINT CTLR (SAM) IN SAN FRANCISCO, CA, AND ROUTINELY PROVIDE ASSISTANCE TO FLCS AS PROBS DEVELOP WITH ACFT INFLT OR ON THE GND. I WAS INVOLVED IN A SIT THAT RESULTED IN A CONDITION WHICH AFFECTED THE GND OPERATIONAL PERFORMANCE OF AN MLG A ACFT ON LNDG AT SEATTLE ON FLT XXX, MAY/XX/93. THE ACFT LANDED AND RPTED THE #2 ENG REVERSER DID NOT DEPLOY ON LNDG. (FOR INFORMATIONAL PURPOSES, THE #1 ENG REVERSER SYS HAD BEEN DEFERRED INOP ON MAY/XX/93 AT MSY AND SHOULD HAVE BEEN DEACTIVATED PER SPECIAL PROC). I HAD RECEIVED A RADIO CALL FROM FLT AFTER DEP AT DENVER. THE CREW RPTED THEY HAD AN 'ENG' LIGHT ON THE FORWARD PANEL 6 PACK ANNUNCIATOR MODULE WHEN THE RECALL CHK WAS DONE. NO OTHER ENG ASSOCIATED FAULTS WERE OBSERVED OR RPTED. THIS LIGHT COULD HAVE BEEN CAUSED BY AN ENG REVERSER FAULT CONDITION. WHEN I REVIEWED THE ACFT CURRENT DEFERRED ITEMS, I SAW THAT THE #1 ENG REVERSER WAS INOP. I ASKED THE CREW TO CHK AND SEE IF THE ENG REVERSER CTL CIRCUIT BREAKER WAS PULLED ON THE PANEL AS REQUIRED BY THE INOP REVERSER PROC. THE CREW ADVISED THAT NO CIRCUIT BREAKERS WERE FOUND OUT. TO COMPLY, I ADVISED THE CREW TO PULL THE ENG CTL CIRCUIT BREAKER AT GRID LOCATION C-6. I HAD DETERMINED THIS CIRCUIT BREAKER LOCATION USING THE MLG QUICK REF CIRCUIT BREAKER DIAGRAM FOR AN MLG B ACFT. I ASSUMED THAT THIS WAS THE CORRECT CIRCUIT BREAKER FOR THE #1 ENG REVERSER CTL SYS. THE CIRCUIT BREAKER IS NOT IDENTED BY ENG POS AND BEING LOCATED ON THE L SIDE OF THE PANEL AS VIEWED, ONE MIGHT ASSUME THAT IT WOULD BE FOR THE L OR #1 ENG. THE CREW DID NOT RPT ANY FURTHER PROBS WITH THE 'ENG' LIGHT SO I THOUGHT THE SIT HAD BEEN CORRECTED. I THEN CONTACTED SEATTLE MAINT AND REQUESTED THAT THEY CHK THE ACFT ON ARR AND CONFIRM THAT REVERSER DEACTIVATION PROCS HAD BEEN COMPLIED WITH. SEATTLE MAINT FOUND THAT THE #1 ENG REVERSER CTL CIRCUIT BREAKER HAD NOT BEEN PULLED AS SPECIFIED. THE #2 REVERSER CIRCUIT BREAKER, HOWEVER, WAS FOUND OUT AND WAS THE REASON THAT THE #2 REVERSER DID NOT DEPLOY ON LNDG. IN THE FUTURE I PLAN TO EXERCISE MORE CAUTION WHEN RESEARCHING AND ADVISING CIRCUIT BREAKER LOCATIONS AND HOPE THIS SIT WILL NOT RECUR. I FEEL, HOWEVER, THAT FLCS HAVE SOME RESPONSIBILITY IN THIS TYPE OF A SIT TO CHALLENGE AND CONFIRM THESE ACTIONS AS WELL AS BE AWARE OF THE MAINT STATUS OF THEIR ACFT.

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.