As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DESCENT OUT OF FL240, LT ENGINE SURGED FROM 0 PERCENT TO 30 PERCENT TORQUE AND LT PROP IMMEDIATELY WENT TO 103 PERCENT NP. FLEW FOR 4 MINUTES WITH ENGINE AT FLT IDLE AND NP AT 103 PERCENT. ENGINE SURGED 2ND TIME CAUSING ACFT TO YAW. ELECTED TO SHUTDOWN ENGINE. MAX NP WAS 106 PERCENT. PROP WAS IN A PITCH LOCK SITUATION AND THEN FEATHERED NORMALLY. MAINTENANCE REMOVED AND REPLACED LT ENGINE.