A B727-100 WAS PARKED ON THE GATE AND USING GND PWR WITH THE ENGS RUNNING WHEN THE GND PWR WAS DISCONNECTED AND BEFORE ENG BUSSES WERE PWRING THE ACFT THE #2 ENG FLAMED OUT.

Narrative

ACFT APU INOP. STARTED ALL 3 ENGS IN BLOCKS USING EXTERNAL PWR AND AIR. AFTER STARTING ENGS; MAINT ASKED IF THEY COULD REMOVE AIR AND ELECTRICS. I REPLIED YES AND TURNED TO TELL SO TO SWITCH TO SHIP'S PWR. THE MECH WAS QUICKER. THERE WAS A MOMENTARY INTERRUPTION OF ELECTRICAL PWR UNTIL THE SO GOT US ONTO SHIP'S PWR. WE THEN NOTICED THAT #2 ENG HAD FLAMED OUT. WE IMMEDIATELY SELECTED THE START LEVER TO CUT-OFF. WE ADVISED MAINT; AND AFTER THE ENG SPOOLED DOWN WE MOTORED IT TO CLR ANY RESIDUAL FUEL AND MADE A NORMAL START. THE REMAINDER OF THE FLT WAS UNEVENTFUL. NO WRITE-UP WAS MADE. HAD WE SWITCHED TO SHIP'S PWR BEFORE THE MECH PULLED ELECTRICS THE ENG PROBABLY WOULD NOT HAVE FLAMED OUT. HOWEVER; THE DESIGN IS FLAWED IF A MOMENTARY LOSS OF ELECTRICS CAUSES AN ENG TO FLAME OUT. THIS ACFT HAS BEEN MODIFIED WITH ROLLS- ROYCE TAY ENGS AND WE HAVE EXPERIENCED SEVERAL SIMILAR INCIDENTS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THIS FLAMEOUT SIT HAS HAPPENED SEVERAL TIMES AND THE CAUSE IS KNOWN. THE RPTR SAID THE ENG DRIVEN FUEL PUMP WILL NOT SUCK FUEL FROM THE TANK AND WHEN THE TANK BOOST PUMPS COME ON A FUEL SURGE OCCURS THAT THE FUEL CTL CANNOT PROCESS. THE RPTR STATED SEVERAL FIXES HAVE BEEN TRIED BUT NONE SUCCESSFUL. THE RPTR SAID THEY GET AROUND THIS BY USING PROCS LIKE HAVING THE BUSSES PWRED WITH TANK PUMPS RUNNING AT ENG START AND THEN SWITCHING THE ENG GENERATORS ON BEFORE REMOVING THE GND PWR. THE RPTR ADVISED THIS ACFT IS PWRED BY THE ROLLS-ROYCE TAY ENGS AND THE STC HOLDER HAS TRIED FUEL PRESSURE REGULATORS AND ACCUMULATORS WITH NO SUCCESS. THE RPTR STATED THIS DESIGN IS FLAWED. CALLBACK CONVERSATION WITH RPTR ACN 384394 REVEALED THE FOLLOWING INFO: RPTR STATED THE FOLLOWING CONDITIONS EXISTED AT THE TIME THE ENG FLAMED OUT: THE ENGS WERE RUNNING WITH GND PWR PWRING ALL BUSSES THROUGH THE BUS TIE BREAKERS AND THE ACFT AND TANK BOOST PUMPS FEEDING THE ENGS. THE RPTR SAID THE MECH PULLED THE GND PWR BEFORE THE ENG GENERATORS WERE SWITCHED ONTO THE INDIVIDUAL BUSSES. THE RPTR STATED WHEN THE ENG BUSSES WERE PWRED AND THE BOOST PUMPS OPERATED THE ENG FLAMED OUT. THE RPTR RELATED THAT THIS PWR INTERRUPTION AND ENG FLAMEOUT SIT HAS OCCURRED SEVERAL TIMES WITH THIS ACFT CONFIGN.