Narrative:

I was on a cross-country training flight with a student where we experienced a partial loss of power on our right engine (approximately 50%); that was indicated. I took control of the aircraft; disengaged the autopilot; and established aircraft control. When aircraft control was established; I determined that we needed to divert to a different airport. I notified ATC of the partial engine failure. We were in the vicinity of ZZZ airport; in between ZZZ and ZZZ1; at 12;500 at the time of the failure. After the failure occurred and had control of the aircraft; I turned the aircraft back to the south and assessed my landing options. Ultimately; I deemed it safe to return to our home airport ZZZ2 due to the high altitude we were at; with adequate airspeed and performance. I chose not to land at ZZZ1 because I wanted to get the plane back to our home airport; and it wasn't beyond reasonable distance to fly the aircraft to ZZZ2. I then troubleshot the issue in an attempt to fix the engine. After proceeding with the appropriate checklists and personal assessments of the aircraft; I determined that the damage was done internally to the engine and could not be fixed in flight. However; I chose not to feather our right engine due to the issues on aircraft control that would present; and we were still receiving some power on the affected engine. I confirmed that the remaining engine was still producing some power by the performance that we were achieving; which was approximately 500 fpm climb and could obtain approximately 110 kias in level flight. On the way back to ZZZ2; I requested the ILS/localizer rwy 13 approach into ZZZ2. Approach stayed with us the whole time on the flight and terminated our radar services approximately 8 miles north of ZZZ2 airport. They then notified me to inform once I got on the ground. After we were safely on the ground; I notified approach that we were safely on the ground. Approach notified emergency services of the issue; in which they met us on the ground. I told them that we did not need any assistance.

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Original NASA ASRS Text

Title: DA42 CFI reported a power loss on one engine and successful return to departure airport on a night cross country flight.

Narrative: I was on a cross-country training flight with a student where we experienced a partial loss of power on our right engine (approximately 50%); that was indicated. I took control of the aircraft; disengaged the autopilot; and established aircraft control. When aircraft control was established; I determined that we needed to divert to a different airport. I notified ATC of the partial engine failure. We were in the vicinity of ZZZ airport; in between ZZZ and ZZZ1; at 12;500 at the time of the failure. After the failure occurred and had control of the aircraft; I turned the aircraft back to the South and assessed my landing options. Ultimately; I deemed it safe to return to our home airport ZZZ2 due to the high altitude we were at; with adequate airspeed and performance. I chose not to land at ZZZ1 because I wanted to get the plane back to our home airport; and it wasn't beyond reasonable distance to fly the aircraft to ZZZ2. I then troubleshot the issue in an attempt to fix the engine. After proceeding with the appropriate checklists and personal assessments of the aircraft; I determined that the damage was done internally to the engine and could not be fixed in flight. However; I chose not to feather our right engine due to the issues on aircraft control that would present; and we were still receiving some power on the affected engine. I confirmed that the remaining engine was still producing some power by the performance that we were achieving; which was approximately 500 fpm climb and could obtain approximately 110 kias in level flight. On the way back to ZZZ2; I requested the ILS/LOC Rwy 13 approach into ZZZ2. Approach stayed with us the whole time on the flight and terminated our radar services approximately 8 miles North of ZZZ2 airport. They then notified me to inform once I got on the ground. After we were safely on the ground; I notified Approach that we were safely on the ground. Approach notified emergency services of the issue; in which they met us on the ground. I told them that we did not need any assistance.

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.