Narrative:

During climbout we began to notice that the right engine was making a banging/knock sound which would cause the engine to shudder for a brief moment. We weren't sure if it was just a momentary thing but it began to happen over and over and we did not feel it was safe to continue flight in the aircraft. We [advised ATC] and requested flight back to [departure airport] since the engine was still running and all engine indications were normal. I informed the passengers that we were having mechanical troubles and would be returning. We continued flight as normal and landed without incident.

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Original NASA ASRS Text

Title: Small transport pilot reported returning to departure airport after noticing abnormal noises coming from the right engine.

Narrative: During climbout we began to notice that the right engine was making a banging/knock sound which would cause the engine to shudder for a brief moment. We weren't sure if it was just a momentary thing but it began to happen over and over and we did not feel it was safe to continue flight in the aircraft. We [advised ATC] and requested flight back to [departure airport] since the engine was still running and all engine indications were normal. I informed the passengers that we were having mechanical troubles and would be returning. We continued flight as normal and landed without incident.

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.