Narrative:

On takeoff we were in a turn between 4;000 feet and 5;000 feet MSL when we heard a bang and vibration coming from the left side of the aircraft behind the cockpit. We discussed what it could be and I contacted the flight attendant to inquire what she was hearing. The flight attendant reported loud noise in first class on left side of aircraft. Engine instruments were normal. I decided to return to the airport to get it checked out; as it was obviously not normal. As we reduced power on the engines in preparation for returning to the airport; the vibration and noise returned to normal level. I [notified ATC of our situation] and landed uneventfully. Upon arrival at the gate; we were informed that we had a large bird strike on the left engine that damaged the engine cowling and blades. Did not see or know that we had struck a bird until we were on the ground.

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Original NASA ASRS Text

Title: A320 flight crew reported returning to departure airport after experiencing a bird strike climbing through 5;000 feet. Ground inspection revealed damage to the left engine.

Narrative: On takeoff we were in a turn between 4;000 feet and 5;000 feet MSL when we heard a bang and vibration coming from the left side of the aircraft behind the cockpit. We discussed what it could be and I contacted the Flight Attendant to inquire what she was hearing. The Flight Attendant reported loud noise in First Class on left side of aircraft. Engine instruments were normal. I decided to return to the airport to get it checked out; as it was obviously not normal. As we reduced power on the engines in preparation for returning to the airport; the vibration and noise returned to normal level. I [notified ATC of our situation] and landed uneventfully. Upon arrival at the gate; we were informed that we had a large bird strike on the left engine that damaged the engine cowling and blades. Did not see or know that we had struck a bird until we were on the ground.

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.