Narrative:

On climbout we experienced a series of bangs and the aircraft yawed a number of times. This appeared to originate from the left engine. We handled the problem; declared an emergency and returned back to [departure airport].

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Original NASA ASRS Text

Title: A B757-200 experienced a compressor stall on takeoff. The flight crew ran the procedures; declared an emergency; and returned to departure airport.

Narrative: On climbout we experienced a series of bangs and the aircraft yawed a number of times. This appeared to originate from the left engine. We handled the problem; declared an emergency and returned back to [departure airport].

Data retrieved from NASA's ASRS site as of April 2012 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.