Narrative:

We were on VFR flight following. We were in descent from 9;500 MSL with a 35-40 NM/hour quartering tailwind. The engine began to run rough and lose power. I felt a total loss of power was imminent and called a 'mayday' to approach who I was connected to via VFR flight following. I was very near an airport and initiated an emergency descent for landing and the power continued to lessen. Approach asked for souls on board and fuel. At approximately 3;000 MSL I switched fuel tanks; applied full power; the automatic alternate air door engaged; and I applied full rich mixture. Adequate power returned to sustain flight. I aborted the emergency descent; leveled; and asked approach for direct to my destination airport and was shortly granted direct to the runway by approach. I was able to maintain approximately 3;200 MSL but engine instruments indicated excessive manifold pressure. I was able to maintain fuel mixture and throttle to maintain altitude and return engine instruments to the high end of the 'green' operating range. The tower controller cleared me to land on the runway and a normal full stop landing was made. I was able to taxi to the hangar and will contact on field mechanics for assistance. I am submitting the form as I called for help via a 'mayday' call to approach. My wife was on board; also a sel private pilot of 250+ hours. We greatly appreciated the professionalism and prompt handling by approach and the tower controllers.

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Original NASA ASRS Text

Title: A SR22 pilot experienced a power loss as a result of a fuel control mis adjustment so he declared an emergency while completing the emergency procedures which ultimately restored enough power that he undeclared the emergency and landed at his nearby destination.

Narrative: We were on VFR flight following. We were in descent from 9;500 MSL with a 35-40 NM/HR quartering tailwind. The engine began to run rough and lose power. I felt a total loss of power was imminent and called a 'mayday' to Approach who I was connected to via VFR flight following. I was very near an airport and initiated an emergency descent for landing and the power continued to lessen. Approach asked for souls on board and fuel. At approximately 3;000 MSL I switched fuel tanks; applied full power; the automatic alternate air door engaged; and I applied full rich mixture. Adequate power returned to sustain flight. I aborted the emergency descent; leveled; and asked Approach for direct to my destination airport and was shortly granted direct to the runway by Approach. I was able to maintain approximately 3;200 MSL but engine instruments indicated excessive manifold pressure. I was able to maintain fuel mixture and throttle to maintain altitude and return engine instruments to the high end of the 'green' operating range. The Tower Controller cleared me to land on the runway and a normal full stop landing was made. I was able to taxi to the hangar and will contact on field mechanics for assistance. I am submitting the form as I called for help via a 'MAYDAY' call to Approach. My wife was on board; also a SEL private pilot of 250+ hours. We greatly appreciated the professionalism and prompt handling by Approach and the Tower Controllers.

Data retrieved from NASA's ASRS site as of July 2013 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.