Narrative:

We were en route from bos to roc on a step-up climb. Before entering the cloud layer we turned on the engine anti-ice. Shortly afterwards the right anti-ice air valve light came on. We followed the abnormal checklist. First we reset the switch which did not correct the problem. The checklist then calls for a power reduction to a specified engine RPM, which we did. We then got a power interruption (rollback) and we requested (from ATC) the tops of the clouds. At this point we hoped to climb out of the icing conditions. We then got another rollback and requested a descent to clear the icing conditions. We descended and got clear of the clouds, then we added power to the right engine. The oil pressure light came on, and we confirmed that the right engine had failed,and not relit. We used the emergency engine failure checklist and the abnormal one engine inoperative checklist, secured the engine, declared an emergency with mht approach, and requested an immediate landing on runway 35 at manchester. We landed successfully with no further problems. I believe that the engine anti-ice system on the saab 350 (ge) needs improvement. Rollbacks are a too common occurrence. Callback conversation with reporter revealed the following information: this reporter glanced at the flight data recorder information when it was first pulled, and the problem appears to involve a combination of a stuck P3 air valve, and the malfunction of the autocoarsen and anti-ice system. The reporter believes that the autocoarsen switch was not armed, but there is evidence that the propeller was feathering when the flight crew shut down the engine. All of the parameters, except switch position, for autocoarsen were met when the flight crew reduced power according to the abnormal checklist procedures for the illumination of the anti-ice air valve light. The autocoarsen system's parameters include one torque above 50%, one torque below 50%, one P3 above 120, one P3 below 120, and both power lever quadrant switches above 64%. Regardless of the final analysis of this flight crew's experience, this reporter does not feel comfortable with the overlap of the autocoarsen parameters and the abnormal checklist anti-ice air valve procedures. The outcome of this combination of the armed autocoarsen system and reduced power during a non precision approach could set a crew up for a like experience close to the ground. Further complicating flight crew response is the fact that only one annunciator illuminates for both engine oil pressure and propeller oil pressure -- reporter feels that this requires excessive attention in a critical situation. Supplemental information from acn 348349: once leaving icing conditions, (visible moisture, OAT +10 degrees C and below) I reintroduced power to the right engine. At approximately 60% torque, the right engine failed. We secured the engine using the engine failure checklist. We declared an emergency and landed uneventfully at mht airport. After running up the engine with a mechanic, mr. X, itt was observed (790 itt). After he did additional work we ran up again with normal indications. We then ferried aircraft to psm for maintenance. This aircraft had had a history of problems in this area with both airframe and engine icing events. I have personally been involved with an airframe icing event with this aircraft and filed a report in the past. It is my belief that a review of the icing certification is in order!

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Original NASA ASRS Text

Title: THE ANTI-ICE AIR VALVE LIGHT ILLUMINATED ON AN SF34 DURING A CLB IN ICING CONDITIONS. WHEN THE FLC FOLLOWED ABNORMAL CHKLIST PROCS AND THEY REDUCED PWR, THEY NOTICED A PWR INTERRUPTION. THE ACFT WAS DSNDED OUT OF ICING CONDITIONS AND WHEN THE CREW ADDED PWR TO THE R ENG, THE OIL PRESSURE LIGHT CAME ON AND THE CREW FOLLOWED PROCS FOR AN ENG FAILURE. AN EMER WAS DECLARED AND THE FLT WAS DIVERTED.

Narrative: WE WERE ENRTE FROM BOS TO ROC ON A STEP-UP CLB. BEFORE ENTERING THE CLOUD LAYER WE TURNED ON THE ENG ANTI-ICE. SHORTLY AFTERWARDS THE R ANTI-ICE AIR VALVE LIGHT CAME ON. WE FOLLOWED THE ABNORMAL CHKLIST. FIRST WE RESET THE SWITCH WHICH DID NOT CORRECT THE PROB. THE CHKLIST THEN CALLS FOR A PWR REDUCTION TO A SPECIFIED ENG RPM, WHICH WE DID. WE THEN GOT A PWR INTERRUPTION (ROLLBACK) AND WE REQUESTED (FROM ATC) THE TOPS OF THE CLOUDS. AT THIS POINT WE HOPED TO CLB OUT OF THE ICING CONDITIONS. WE THEN GOT ANOTHER ROLLBACK AND REQUESTED A DSCNT TO CLR THE ICING CONDITIONS. WE DSNDED AND GOT CLR OF THE CLOUDS, THEN WE ADDED PWR TO THE R ENG. THE OIL PRESSURE LIGHT CAME ON, AND WE CONFIRMED THAT THE R ENG HAD FAILED,AND NOT RELIT. WE USED THE EMER ENG FAILURE CHKLIST AND THE ABNORMAL ONE ENG INOP CHKLIST, SECURED THE ENG, DECLARED AN EMER WITH MHT APCH, AND REQUESTED AN IMMEDIATE LNDG ON RWY 35 AT MANCHESTER. WE LANDED SUCCESSFULLY WITH NO FURTHER PROBS. I BELIEVE THAT THE ENG ANTI-ICE SYS ON THE SAAB 350 (GE) NEEDS IMPROVEMENT. ROLLBACKS ARE A TOO COMMON OCCURRENCE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS RPTR GLANCED AT THE FLT DATA RECORDER INFO WHEN IT WAS FIRST PULLED, AND THE PROB APPEARS TO INVOLVE A COMBINATION OF A STUCK P3 AIR VALVE, AND THE MALFUNCTION OF THE AUTOCOARSEN AND ANTI-ICE SYS. THE RPTR BELIEVES THAT THE AUTOCOARSEN SWITCH WAS NOT ARMED, BUT THERE IS EVIDENCE THAT THE PROP WAS FEATHERING WHEN THE FLC SHUT DOWN THE ENG. ALL OF THE PARAMETERS, EXCEPT SWITCH POS, FOR AUTOCOARSEN WERE MET WHEN THE FLC REDUCED PWR ACCORDING TO THE ABNORMAL CHKLIST PROCS FOR THE ILLUMINATION OF THE ANTI-ICE AIR VALVE LIGHT. THE AUTOCOARSEN SYS'S PARAMETERS INCLUDE ONE TORQUE ABOVE 50%, ONE TORQUE BELOW 50%, ONE P3 ABOVE 120, ONE P3 BELOW 120, AND BOTH PWR LEVER QUADRANT SWITCHES ABOVE 64%. REGARDLESS OF THE FINAL ANALYSIS OF THIS FLC'S EXPERIENCE, THIS RPTR DOES NOT FEEL COMFORTABLE WITH THE OVERLAP OF THE AUTOCOARSEN PARAMETERS AND THE ABNORMAL CHKLIST ANTI-ICE AIR VALVE PROCS. THE OUTCOME OF THIS COMBINATION OF THE ARMED AUTOCOARSEN SYS AND REDUCED PWR DURING A NON PRECISION APCH COULD SET A CREW UP FOR A LIKE EXPERIENCE CLOSE TO THE GND. FURTHER COMPLICATING FLC RESPONSE IS THE FACT THAT ONLY ONE ANNUNCIATOR ILLUMINATES FOR BOTH ENG OIL PRESSURE AND PROP OIL PRESSURE -- RPTR FEELS THAT THIS REQUIRES EXCESSIVE ATTN IN A CRITICAL SIT. SUPPLEMENTAL INFO FROM ACN 348349: ONCE LEAVING ICING CONDITIONS, (VISIBLE MOISTURE, OAT +10 DEGS C AND BELOW) I REINTRODUCED PWR TO THE R ENG. AT APPROX 60% TORQUE, THE R ENG FAILED. WE SECURED THE ENG USING THE ENG FAILURE CHKLIST. WE DECLARED AN EMER AND LANDED UNEVENTFULLY AT MHT ARPT. AFTER RUNNING UP THE ENG WITH A MECH, MR. X, ITT WAS OBSERVED (790 ITT). AFTER HE DID ADDITIONAL WORK WE RAN UP AGAIN WITH NORMAL INDICATIONS. WE THEN FERRIED ACFT TO PSM FOR MAINT. THIS ACFT HAD HAD A HISTORY OF PROBS IN THIS AREA WITH BOTH AIRFRAME AND ENG ICING EVENTS. I HAVE PERSONALLY BEEN INVOLVED WITH AN AIRFRAME ICING EVENT WITH THIS ACFT AND FILED A RPT IN THE PAST. IT IS MY BELIEF THAT A REVIEW OF THE ICING CERTIFICATION IS IN ORDER!

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.