Narrative:

We were shooting a VOR approach to runway 35C manchester, nh, as part of an engineering evaluation of the manchester VOR. From the procedure turn inbound we had descended from 2000' crossing the VOR at 1600', we continued descending to minimums of 800' and then to 100' below minimums to conform with flight check procedures. I raised the gear, propellers at 2400 RPM and 20' of manifold pressure, we continued across the airport marking each end of the runway. Getting ready to climb out tower called and told me to switch to departure control and I switched approach plates to do the VOR approach to runway 17. I told departure control our intentions and started a climb moving the propellers to 2500 RPM and power to 25' of manifold pressure, the left engine RPM wouldn't increase beyond 1700 RPM. I moved the propeller levers full forward and the left engine RPM wouldn't increase beyond 1700 RPM. I added full throttle and rechked the mixture controls for full rich. We continued a climb to around 1600' and started turning left away from the city. I switched the left fuel pump to high boost to see if it made a difference and it didn't. I rechked main tank selection of the tanks and rechked propeller, throttle and mixture positions. I also notified tower that we had an engine problem, I feathered the left engine and started reducing the left throttle when the engine seized. I moved the left throttle forward enough to get rid of the horn and notified tower we were flying back to nashua. The distance to nashua airport was approximately 5 mi farther then going into manchester but I needed a little extra time to prepare for a single engine approach and landing and since we were headed for nashua st level I felt this was safer then circling manchester single engine to prepare for a landing at manchester. The rest of the flight was uneventful. The middle outboard cylinder on the left engine had separated from the engine causing a power loss and loss of engine oil. I had enough oil pressure to feather the engine but it seized up. There was still 3-4 qts of oil in the engine sump. I used the power I had from both engines to gain altitude rather than immediately feather and shutdown the engine that had partial power, in my judgement this was the best decision under the circumstances.

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Original NASA ASRS Text

Title: TWIN SMA FLT CHECKING NAVAID EXPERIENCES ENGINE FAILURE.

Narrative: WE WERE SHOOTING A VOR APCH TO RWY 35C MANCHESTER, NH, AS PART OF AN ENGINEERING EVALUATION OF THE MANCHESTER VOR. FROM THE PROC TURN INBND WE HAD DSNDED FROM 2000' XING THE VOR AT 1600', WE CONTINUED DSNDING TO MINIMUMS OF 800' AND THEN TO 100' BELOW MINIMUMS TO CONFORM WITH FLT CHK PROCS. I RAISED THE GEAR, PROPS AT 2400 RPM AND 20' OF MANIFOLD PRESSURE, WE CONTINUED ACROSS THE ARPT MARKING EACH END OF THE RWY. GETTING READY TO CLB OUT TWR CALLED AND TOLD ME TO SWITCH TO DEP CTL AND I SWITCHED APCH PLATES TO DO THE VOR APCH TO RWY 17. I TOLD DEP CTL OUR INTENTIONS AND STARTED A CLB MOVING THE PROPS TO 2500 RPM AND PWR TO 25' OF MANIFOLD PRESSURE, THE L ENG RPM WOULDN'T INCREASE BEYOND 1700 RPM. I MOVED THE PROP LEVERS FULL FORWARD AND THE L ENG RPM WOULDN'T INCREASE BEYOND 1700 RPM. I ADDED FULL THROTTLE AND RECHKED THE MIXTURE CTLS FOR FULL RICH. WE CONTINUED A CLB TO AROUND 1600' AND STARTED TURNING L AWAY FROM THE CITY. I SWITCHED THE L FUEL PUMP TO HIGH BOOST TO SEE IF IT MADE A DIFFERENCE AND IT DIDN'T. I RECHKED MAIN TANK SELECTION OF THE TANKS AND RECHKED PROP, THROTTLE AND MIXTURE POSITIONS. I ALSO NOTIFIED TWR THAT WE HAD AN ENG PROB, I FEATHERED THE L ENG AND STARTED REDUCING THE L THROTTLE WHEN THE ENG SEIZED. I MOVED THE L THROTTLE FORWARD ENOUGH TO GET RID OF THE HORN AND NOTIFIED TWR WE WERE FLYING BACK TO NASHUA. THE DISTANCE TO NASHUA ARPT WAS APPROX 5 MI FARTHER THEN GOING INTO MANCHESTER BUT I NEEDED A LITTLE EXTRA TIME TO PREPARE FOR A SINGLE ENG APCH AND LNDG AND SINCE WE WERE HEADED FOR NASHUA ST LEVEL I FELT THIS WAS SAFER THEN CIRCLING MANCHESTER SINGLE ENG TO PREPARE FOR A LNDG AT MANCHESTER. THE REST OF THE FLT WAS UNEVENTFUL. THE MIDDLE OUTBOARD CYLINDER ON THE L ENG HAD SEPARATED FROM THE ENG CAUSING A PWR LOSS AND LOSS OF ENG OIL. I HAD ENOUGH OIL PRESSURE TO FEATHER THE ENG BUT IT SEIZED UP. THERE WAS STILL 3-4 QTS OF OIL IN THE ENG SUMP. I USED THE PWR I HAD FROM BOTH ENGS TO GAIN ALT RATHER THAN IMMEDIATELY FEATHER AND SHUTDOWN THE ENG THAT HAD PARTIAL PWR, IN MY JUDGEMENT THIS WAS THE BEST DECISION UNDER THE CIRCUMSTANCES.

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.