AN MD11 WAS DISPATCHED WITH A KNOWN APU FUEL SUPPLY LINE LEAK DEFERRED IN NON COMPLIANCE. ACTUAL CONDITION WAS A FUEL LEAK INTO AN ADJACENT COMPARTMENT.

Narrative

ON DEC/XA/98; TECH SVC RECEIVED A CALL FOR A PLACARD FOR AN INOP APU. THE REASON FOR THE PLACARD WAS STATED AS 'THE APU IS INOP' AND THE PLACARD WAS ISSUED. 15-30 MINS LATER; ANOTHER CALL WAS RECEIVED FROM ZZZ. DURING THIS CONVERSATION THE REAL REASON FOR THE PLACARD WAS REVEALED. FUEL WAS LEAKING FROM THE WEEP HOLES AT DOOR COMPARTMENT FORWARD OF APU AND BY PLACARDING THE APU; THE IGNITION SOURCE WAS ELIMINATED. KNOWING THIS; TECH SVC WOULD HAVE NOT ISSUED A PLACARD; INSTEAD ZZZ WOULD HAVE BEEN ADVISED TO LOCATE THE SOURCE AND ELIMINATE IT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE RPTR TOOK THE FIRST CALL FROM THE ZZZ FOREMAN ADVISING THAT THE APU WAS DEFERRED AS INOP BUT NOT THE REASON WHY. THE RPTR SAID THE FOREMAN ALSO SAID THE ACFT WAS DISPATCHED AND HAD LEFT THE STATION. THE RPTR STATED THAT AFTER SHIFT CHANGE IN THE MAINT CTL CTR THE FOREMAN FROM ZZZ ADVISED ANOTHER MAINT CTLR OF THE PROB WITH THE APU FUEL SUPPLY LINE LEAK WHICH WAS A NO GO ITEM AND COULD NOT BE DEFERRED UNDER ANY CONDITIONS. THE RPTR SAID THE ACFT WAS STOPPED AT THE NEXT STATION AND REMOVED FROM SVC. THE RPTR STATED THE FOREMAN SHOULD HAVE BEEN ASKED WHY THE APU WAS INOP BUT IT WOULD NOT HAVE MATTERED SINCE THE ACFT WAS ALREADY GONE. THE RPTR SAID THE RPTR HAD 8 YRS EXPERIENCE AS A MECH AND 1 YR AS A MAINT CTLR. SUPPLEMENTAL INFO FROM ACN 421800: ZZZ MAINT SUPVR YYXYZ CALLED AT XB05 TO INFORM ME THAT THE REASON HE PLACARDED THE APU INOP WAS TO ELIMINATE AN IGNITION SOURCE FOR A FUEL LEAK IN A COMPARTMENT FORWARD OF THE APU. THE LEAK STOPPED WHEN APPROX 6 QUARTS OF FUEL WAS DRAINED FROM THE FORWARD SHROUD DRAIN.