DURING THE 4TH ATTEMPTED ENG START OF AN MDT TURBO PROP; THERE WAS TAILPIPE FIRE WHICH IN TURN STARTED THE FUEL RESIDUE DRIP PAN FUEL ON FIRE. THE PAX WERE EVACED AND THE FIRE PUT OUT BY THE CAPT DISCHARGING THE ENG FIRE BOTTLES.

Narrative

AFTER 3 UNSUCCESSFUL STARTS; CONFERRING WITH OUR MAINT AND WAITING THE APPROPRIATE TIME; WE TRIED A 4TH START ON #1 ENG. DURING THE START WE HAD FLAMES COMING OUT THE TAILPIPE (NOT UNUSUAL WITH A TURBINE AFTER FAILED STARTS). WHEN THE FLAMES LASTED LONGER THEN NORMAL THE GND CREW MEMBER INDICATED 'CUT.' SIMULTANEOUSLY; THE FO NOTED THE REFLECTION OF THE FLAMES ON THE TERMINAL. WE SHUT DOWN THE ENG AND MOTORED IT TO CLR EXCESS FUEL. A MIN OR TWO LATER; AFTER THE DOOR WAS OPEN; AS WE WERE PREPARING TO DEPLANE PAX THE GND CREW MEMBER YELLED UP TO 'GET EVERYONE OFF; YOU'RE STILL ON FIRE.' THE FLT ATTENDANT QUICKLY EVACED EVERYONE WHILE I DISCHARGED THE FIRE BOTTLES. AT NO TIME DID WE GET A FIRE INDICATION IN THE COCKPIT. MAINT FOUND A STUCK FUEL DRAIN/DUMP VALVE WHICH CAUSED THE FUEL (AT SHUTDOWN) TO POOL IN THE ENG; RESULTING IN THE SECONDARY 'FIRE.' NO INJURIES NOR SEVERE DAMAGE TO ACFT. LESSONS LEARNED. THERE IS STILL NO GND SIGNAL FOR AN ENG FIRE -- THE 'CUT' SIGN MAY NOT ALWAYS BE APPROPRIATE. WE WERE USING A COMPANY FREQ ON THE RADIO; WHICH TAKES LONGER TO NOTIFY EQUIP THAN SWITCHING TO GND CTL WHO HAVE A DIRECT LINE. THE SYS WORKS; AS DO OUR PROCS; BUT MINOR DETAILS; IE; CORRECT GND CREW SIGNALS AND RADIOS CAN SPD UP PROC.