B737-500 CREW HAD A BLOWN #2 ENG STARTER AT SEA.

Narrative

WHILE STARTING #2 ENG DURING PUSHBACK; THE FO OBSERVED N2 DECAY IMMEDIATELY AFTER LIGHT OFF. WE ACCOMPLISHED THE QRC MEMORY ITEMS; AND I CALLED FOR THE ABNORMAL ENG START QRC. AS THE FO GOT HER FLT MANUAL OUT; I ADVISED THE TUG DRIVER NOT TO DISCONNECT BECAUSE WE WERE EXPERIENCING A PROB STARTING #2 ENG. HE THEN ADVISED ME THAT HE HAD BEEN OBSERVING SPARKS COMING FROM #2 ENG DURING THE START. I TOLD HIM TO HAVE THE WING WALKER TAKE A LOOK AT THE ENG IMMEDIATELY AND ALSO TO GET ON THE RADIO AND GET MECHS OUT TO US ASAP. DURING THIS TIME; WE COMPLETED THE ABNORMAL ENG START QRC FROM THE FLT MANUAL. THE WING WALKER ADVISED THAT THE ENG APPEARED NORMAL. A MECH APPEARED ALMOST IMMEDIATELY AND CONFIRMED THAT OBSERVATION. WE THEN SHUT DOWN #1 ENG AND WERE TOWED BACK TO THE GATE. THE PARKING CHKLIST WAS ACCOMPLISHED. IN SUBSEQUENT DISCUSSION WITH THE MECHS; THEY ADVISED US THAT IT APPEARED THAT THE #2 STARTER HAD BLOWN; WITH PIECES GOING THROUGH THE ENG COWLING AND INTO THE FUSELAGE. THE ONLY HUMAN FACTOR I FEEL WAS RELEVANT WAS THE FACT THAT THE PUSH CREW HAD OBSERVED SPARKS DURING THE START PROCESS AND DID NOT NOTIFY US IMMEDIATELY. SUPPLEMENTAL INFO FROM ACN 599786: WE BEGAN OUR PUSHBACK AND THE PUSHBACK CREW CLRED US TO START ENGS #1 AND #2. I STARTED ENG #1 WITHOUT INCIDENT AND AFTER BEGAN TO START ENG #2. I STARTED ENG #2 AND GOT NORMAL ENG START INDICATIONS OF 25% N2 AND ROTATION OF N1 THEN I BROUGHT THE START LEVER TO IDLE. WE GOT LIGHT OFF AND THEN N2 STOPPED INCREASING AND THEN BEGAN TO ROLL BACK. I IMMEDIATELY PERFORMED THE IMMEDIATE QRC ACTION FOR AN ABNORMAL ENG START AND BROUGHT THE START LEVER TO CUTOFF AND THE CAPT CALLED FOR THE QRC. WE COMPLETED THE QRC IMMEDIATE ACTION AND REF ITEMS. THE GND CREW CALLED A MECH OUT AND THEY TOLD US THE ENG HAD BLOWN PIECES OF THE STARTER THROUGH THE COWLING AND THEY WOULD TOW US INTO THE GATE. THEY CONFIRMED WE WERE NOT ON FIRE. I THEN CALLED GND CTL FOR CLRNC TO BE TOWED ONTO THE GATE. WE WERE CLRED IN AND THEN SHUT ENG #1 DOWN AND RAN THE PARKING CHKLIST.