Narrative:

Approximately 10 minutes after reaching fl 230; to stay above an active MOA along my route; I experienced a loss of power in the right engine. After gaining control of the aircraft; I started a decent and proceeded to make a right turn to avoid entering the active MOA; since I could not maintain sufficient altitude on a single engine. Passing through fl 190; I was able to bring power back to the right engine. Checking the right main and auxillary fuel tanks showed more than 1/2 each; and lacking the confidence in the right engine to sustain a higher altitude; I requested and was approved to descend to 11;000 MSL. I informed ATC of my engine problem and was asked if I needed assistance; to which I replied I wanted to remain in VMC. Subsequently; I asked for and received a direct to a nearby airport and landed safely. After inspection of the right engine by a local mechanic; it was concluded that apparently the right oil pressure pump had failed causing the engine to lose manifold pressure. The failure of the right engine made the aircraft unable to maintain the assigned altitude.

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Original NASA ASRS Text

Title: A Cessna 421 pilot lost power in the right engine shortly after reaching cruise altitude of FL230. Diverted to a nearby airport even though the engine regained power during the descent to a useable single engine altitude.

Narrative: Approximately 10 minutes after reaching FL 230; to stay above an active MOA along my route; I experienced a loss of power in the right engine. After gaining control of the aircraft; I started a decent and proceeded to make a right turn to avoid entering the active MOA; since I could not maintain sufficient altitude on a single engine. Passing through FL 190; I was able to bring power back to the right engine. Checking the right main and auxillary fuel tanks showed more than 1/2 each; and lacking the confidence in the right engine to sustain a higher altitude; I requested and was approved to descend to 11;000 MSL. I informed ATC of my engine problem and was asked if I needed assistance; to which I replied I wanted to remain in VMC. Subsequently; I asked for and received a direct to a nearby airport and landed safely. After inspection of the right engine by a local Mechanic; it was concluded that apparently the right oil pressure pump had failed causing the engine to lose manifold pressure. The failure of the right engine made the aircraft unable to maintain the assigned altitude.

Data retrieved from NASA's ASRS site as of April 2012 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.