Narrative:

I was an instructor with a private pilot performing a training flight. While at cruise at 7;500 feet the aircraft started to shake. Suspecting the engine was running rough I immediately turned on the fuel pump; pushed the mixture to full rich and switched fuel tanks. These are the immediate action items for engine trouble in a cirrus. I also took over control of the aircraft from the student at this point. None of these actions solved the issue. At this time I notified ATC approach; who we currently were receiving flight following; of the situation. They asked if we needed assistance and I stated that I needed a minute to continue to troubleshoot the problem. I wanted to run through the checklist to see if there was any other steps that might remedy the issue. Approach continued on with questions about the situation and then advised me that ZZZ was at my twelve o'clock. At this point no amount of troubleshooting was solving the issue so I advised approach that we would land at ZZZ. Approach asked for number of souls and fuel on board. I advised that we had to two souls and 3 hours of fuel. We started a descent and headed directly for ZZZ which was right off the nose at this point. I was told to contact ZZZ tower. When I advised ZZZ tower that we were inbound they immediately cleared us to land on runway X and advised us that they had cleared all traffic for us. It was at this point that he asked about our situation and I advised we had a rough running engine but still had power. I then heard tower talk to the emergency vehicles advising them that we still had power. I learned later that the tower was advised by approach that we had lost power and were gliding in. We made a normal landing on runway X and cleared the runway on taxiway charlie. At this point both the student and I noticed a metallic clunking noise coming from the engine and we advised the tower that we had to shutdown. Looking back at the incident I am not sure how approach thought we had lost power. I advised them multiple times that the engine was running but rough.

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Original NASA ASRS Text

Title: SR20 flight instructor reported diverting to a nearby airport due to a rough running engine.

Narrative: I was an instructor with a private pilot performing a training flight. While at cruise at 7;500 feet the aircraft started to shake. Suspecting the engine was running rough I immediately turned on the fuel pump; pushed the mixture to full rich and switched fuel tanks. These are the immediate action items for engine trouble in a Cirrus. I also took over control of the aircraft from the student at this point. None of these actions solved the issue. At this time I notified ATC Approach; who we currently were receiving flight following; of the situation. They asked if we needed assistance and I stated that I needed a minute to continue to troubleshoot the problem. I wanted to run through the checklist to see if there was any other steps that might remedy the issue. Approach continued on with questions about the situation and then advised me that ZZZ was at my twelve o'clock. At this point no amount of troubleshooting was solving the issue so I advised Approach that we would land at ZZZ. Approach asked for number of souls and fuel on board. I advised that we had to two souls and 3 hours of fuel. We started a descent and headed directly for ZZZ which was right off the nose at this point. I was told to contact ZZZ Tower. When I advised ZZZ Tower that we were inbound they immediately cleared us to land on Runway X and advised us that they had cleared all traffic for us. It was at this point that he asked about our situation and I advised we had a rough running engine but still had power. I then heard Tower talk to the emergency vehicles advising them that we still had power. I learned later that the tower was advised by Approach that we had lost power and were gliding in. We made a normal landing on Runway X and cleared the runway on taxiway Charlie. At this point both the student and I noticed a metallic clunking noise coming from the engine and we advised the tower that we had to shutdown. Looking back at the incident I am not sure how Approach thought we had lost power. I advised them multiple times that the engine was running but rough.

Data retrieved from NASA's ASRS site 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.