Narrative:

Aircraft was cleared for pushback tail north. After push; parking brake was set. Auxiliary pump was depressed before push was completed to increase hydraulic pressure. Received propeller brake ready light. Gave signal to ground crew to clear to spin #2 propeller. After receiving clearance to spin propeller; requested first officer to clear right. At this time; propeller brake switch was set to unlock. Propeller stabilized at 13% np. After which; right condition lever was advanced to maximum RPM. Propeller was slow to spin up. Requested ground crew to stand by. Approximately 20 seconds later; received propeller brake warning. Brought condition lever to feather and then to shut off. During this time; the captain and first officer smelled smoke. Contacted flight attendant to investigate possible smoke from #2 engine; and they reported smelling smoke. Approximately 2 seconds after engine shutdown; received #2 engine fire warning. Commenced immediate action items and referenced QRH. Fire was extinguished after agent #1 was depressed. When ready to make PA; noticed that passenger were in the process of evacing in an orderly manner. Requested first officer to ensure that all passenger have deplaned and take fire extinguisher. Contacted ramp; operations; and flight control of situation. First officer returned to flight deck to assist in securing aircraft. No injuries were reported. I believe that the propeller brake somehow failed to fully disengage. This caused the alleged sparks from the engine followed with engine fire. A slow to rise np is not necessarily unique; so a change in response from the flight crew is not warranted; in my opinion. The potential problem with the propeller brake may have been caused by one of several ways. One possibility is a malfunction with the mfc's (multi-function computer). Another is within the propeller brake.

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Original NASA ASRS Text

Title: AN ATR72 ENG FIRE DEVELOPED DURING START AFTER THE PROP BRAKE APPARENTLY DID NOT RELEASE. THE EXTINGUISHING AGENT PUT OUT THE FIRE AS PAX WERE EVACUATING.

Narrative: ACFT WAS CLRED FOR PUSHBACK TAIL N. AFTER PUSH; PARKING BRAKE WAS SET. AUX PUMP WAS DEPRESSED BEFORE PUSH WAS COMPLETED TO INCREASE HYD PRESSURE. RECEIVED PROP BRAKE READY LIGHT. GAVE SIGNAL TO GND CREW TO CLR TO SPIN #2 PROP. AFTER RECEIVING CLRNC TO SPIN PROP; REQUESTED FO TO CLR R. AT THIS TIME; PROP BRAKE SWITCH WAS SET TO UNLOCK. PROP STABILIZED AT 13% NP. AFTER WHICH; R CONDITION LEVER WAS ADVANCED TO MAX RPM. PROP WAS SLOW TO SPIN UP. REQUESTED GND CREW TO STAND BY. APPROX 20 SECONDS LATER; RECEIVED PROP BRAKE WARNING. BROUGHT CONDITION LEVER TO FEATHER AND THEN TO SHUT OFF. DURING THIS TIME; THE CAPT AND FO SMELLED SMOKE. CONTACTED FLT ATTENDANT TO INVESTIGATE POSSIBLE SMOKE FROM #2 ENG; AND THEY RPTED SMELLING SMOKE. APPROX 2 SECONDS AFTER ENG SHUTDOWN; RECEIVED #2 ENG FIRE WARNING. COMMENCED IMMEDIATE ACTION ITEMS AND REFED QRH. FIRE WAS EXTINGUISHED AFTER AGENT #1 WAS DEPRESSED. WHEN READY TO MAKE PA; NOTICED THAT PAX WERE IN THE PROCESS OF EVACING IN AN ORDERLY MANNER. REQUESTED FO TO ENSURE THAT ALL PAX HAVE DEPLANED AND TAKE FIRE EXTINGUISHER. CONTACTED RAMP; OPS; AND FLT CTL OF SITUATION. FO RETURNED TO FLT DECK TO ASSIST IN SECURING ACFT. NO INJURIES WERE RPTED. I BELIEVE THAT THE PROP BRAKE SOMEHOW FAILED TO FULLY DISENGAGE. THIS CAUSED THE ALLEGED SPARKS FROM THE ENG FOLLOWED WITH ENG FIRE. A SLOW TO RISE NP IS NOT NECESSARILY UNIQUE; SO A CHANGE IN RESPONSE FROM THE FLT CREW IS NOT WARRANTED; IN MY OPINION. THE POTENTIAL PROB WITH THE PROP BRAKE MAY HAVE BEEN CAUSED BY ONE OF SEVERAL WAYS. ONE POSSIBILITY IS A MALFUNCTION WITH THE MFC'S (MULTI-FUNCTION COMPUTER). ANOTHER IS WITHIN THE PROP BRAKE.

Data retrieved from NASA's ASRS site as of January 2009 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.