Narrative:

We were turning left base to final for runway 24 at isp approximately 6 NM out, 210 KIAS, WX better than 5000/5, no turbulence. Rate of descent at 1000' FPM. During power reduction from 50% torque through about 30% torque right engine developed a propeller overspd. The first officer was flying. I took control of the aircraft and we went through the appropriate emergency procedure for a propeller overspd. I landed the aircraft, taxied clear of runway 24, stopped the aircraft and we went through all the necessary checklists to secure the engine and aircraft. We then taxied to the gate and deplaned the passenger. I believe this was the result of a mechanical failure. Supplemental information from acn 134912: my hands were not near the lock release mechanism that allows the power levers to go to ground idle from flight idle.

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Original NASA ASRS Text

Title: LTT TURBOPROP EXPERIENCES OVERSPEEDING PROPELLER, SHUTS DOWN ENGINE AND CONTINUES TO LNDG.

Narrative: WE WERE TURNING LEFT BASE TO FINAL FOR RWY 24 AT ISP APPROX 6 NM OUT, 210 KIAS, WX BETTER THAN 5000/5, NO TURB. RATE OF DSCNT AT 1000' FPM. DURING PWR REDUCTION FROM 50% TORQUE THROUGH ABOUT 30% TORQUE RIGHT ENG DEVELOPED A PROP OVERSPD. THE F/O WAS FLYING. I TOOK CTL OF THE ACFT AND WE WENT THROUGH THE APPROPRIATE EMER PROC FOR A PROP OVERSPD. I LANDED THE ACFT, TAXIED CLR OF RWY 24, STOPPED THE ACFT AND WE WENT THROUGH ALL THE NECESSARY CHKLISTS TO SECURE THE ENG AND ACFT. WE THEN TAXIED TO THE GATE AND DEPLANED THE PAX. I BELIEVE THIS WAS THE RESULT OF A MECHANICAL FAILURE. SUPPLEMENTAL INFO FROM ACN 134912: MY HANDS WERE NOT NEAR THE LOCK RELEASE MECHANISM THAT ALLOWS THE PWR LEVERS TO GO TO GND IDLE FROM FLT IDLE.

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.