Narrative:

When checking on with departure after a normal takeoff and climb; ATC informed us that ground personnel reported sparks exiting from our right-hand (number 2) engine during takeoff. We observed no abnormalities of any kind to indicate a problem (vibration; noise; engine parameter readings; power output; etc.). After a short discussion; we elected to return to ZZZ as a precaution and received vectors for ILS runway 31R. We continued to monitor engine indications closely; but at no time observed anything abnormal. ATC asked us numerous times if we required assistance or would like to request priority handling; which we declined as there seemed to be no cause for alarm or need for priority handling. A short time later ATC advised us that ZZZ tower was treating us as a priority aircraft anyway. The remainder of the approach and landing was uneventful. Emergency vehicles escorted us back to the FBO ramp; but did not observe any signs of engine trouble. Shutdown was normal; and a post-flight inspection of visible engine areas revealed no abnormality. A subsequent borescope inspection by maintenance personnel revealed 3 missing blades on the number 2 engine high-pressure compressor and general damage to the entire compressor due to those blades separating during engine operation. I later learned that this is a known issue for this engine.

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Original NASA ASRS Text

Title: C525 Captain reported and return to departure airport after ground observers reported sparks coming from the Number 2 engine tailpipe on takeoff.

Narrative: When checking on with Departure after a normal takeoff and climb; ATC informed us that ground personnel reported sparks exiting from our right-hand (Number 2) engine during takeoff. We observed no abnormalities of any kind to indicate a problem (vibration; noise; engine parameter readings; power output; etc.). After a short discussion; we elected to return to ZZZ as a precaution and received vectors for ILS Runway 31R. We continued to monitor engine indications closely; but at no time observed anything abnormal. ATC asked us numerous times if we required assistance or would like to request priority handling; which we declined as there seemed to be no cause for alarm or need for priority handling. A short time later ATC advised us that ZZZ Tower was treating us as a priority aircraft anyway. The remainder of the approach and landing was uneventful. Emergency vehicles escorted us back to the FBO ramp; but did not observe any signs of engine trouble. Shutdown was normal; and a post-flight inspection of visible engine areas revealed no abnormality. A subsequent borescope inspection by Maintenance Personnel revealed 3 missing blades on the Number 2 engine high-pressure compressor and general damage to the entire compressor due to those blades separating during engine operation. I later learned that this is a known issue for this engine.

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.