What was found
DURING DESCENT FROM 17000 FT TO 15000 FT WITH TORQUE AT 60 PERCENT AND BEING SLIGHTLY RETARDED TO 55 PERCENT, THE LEFT ENGINE FLAMED OUT WITH A LOUD BANG. ALL GAUGES INDICATED FLAME-OUT. AUTO RELIGHT ENGAGED AND THE ENGINE RELIT AND RETURNED TO NORMAL. DURIING THE RETARDATION OF LEFT POWER LEVER AT 55 PERCENT TO 50 PERCENT THE CREW REPORTED A TORQUE SURGE OF APPROXMATELY 5 PERCENT WITH AUDIBLE ENGINE FULX. THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE CLEANED THE LEFT ANTI-ICE VALVE AND PERFORMED AN ENGINE COMPRESSOR WASH. THE ENGINE WAS BORESCOPE, INSPECTED WITH NO DEFECTS FOUND. THE AIRCRAFT WAS RETURNED TO SERVICE WITH NO FURTHER PROBLEMS REPORTED.