Narrative:

En route to lax at 15000 ft, right engine began surging with pronounced changes in torque and temperature. We performed the torque motor lockout procedure, and it seemed to help. We flew for a few more mins, at which point the surging began again, and seemed to get worse. At that point, we were just about over rzs VOR, so we shut down the engine as per the torque motor lockout procedure, declared an emergency, and landed at ZZZ. Callback conversation with reporter revealed the following information: the reporter noted that during the engine surging, the engine torque indication was decreasing and the turbine temperature was going up rapidly. The reporter said the engine was changed, but what component in the engine failed is unknown.

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Original NASA ASRS Text

Title: A SAAB 340B IN CRUISE AT 15000 FT DECLARED AN EMER AND DIVERTED DUE TO THE R ENG SHUTDOWN BECAUSE OF EXCESSIVE SURGING. ENG REPLACED.

Narrative: ENRTE TO LAX AT 15000 FT, R ENG BEGAN SURGING WITH PRONOUNCED CHANGES IN TORQUE AND TEMP. WE PERFORMED THE TORQUE MOTOR LOCKOUT PROC, AND IT SEEMED TO HELP. WE FLEW FOR A FEW MORE MINS, AT WHICH POINT THE SURGING BEGAN AGAIN, AND SEEMED TO GET WORSE. AT THAT POINT, WE WERE JUST ABOUT OVER RZS VOR, SO WE SHUT DOWN THE ENG AS PER THE TORQUE MOTOR LOCKOUT PROC, DECLARED AN EMER, AND LANDED AT ZZZ. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR NOTED THAT DURING THE ENG SURGING, THE ENG TORQUE INDICATION WAS DECREASING AND THE TURBINE TEMP WAS GOING UP RAPIDLY. THE RPTR SAID THE ENG WAS CHANGED, BUT WHAT COMPONENT IN THE ENG FAILED IS UNKNOWN.

Data retrieved from NASA's ASRS site as of July 2007 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.