Narrative:

Takeoff for the functional check flight was normal. Climbing through approximately 12;500 ft with the autothrottles engaged; the airspeed was commanded to slow for a check; as the throttles retarded; the lh engine had 3 or 4 compressor stalls. The ats was disengaged; and the throttles were manually retarded; again the lh engine compressor stalled. The first officer ran the QRH checklist for engine surge or stall. An emergency was declared because we didn't know if damage had been done to the engine and if it would continue to run properly. The engine was not shut down; no parameters were exceeded (i.e. Egt). The engine was left at idle power and we executed a flaps 20 approach and landing as a precautionary step. The landing was uneventful. Arff was on the scene.

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Original NASA ASRS Text

Title: A B767-300 flight crew on a test flight experienced left engine compressor stalls. They reduced thrust; declared an emergency; and returned to departure airport for precautionary landing.

Narrative: Takeoff for the Functional Check Flight was normal. Climbing through approximately 12;500 ft with the autothrottles engaged; the airspeed was commanded to slow for a check; as the throttles retarded; the LH engine had 3 or 4 compressor stalls. The ATS was disengaged; and the throttles were manually retarded; again the LH engine compressor stalled. The F/O ran the QRH checklist for engine surge or stall. An emergency was declared because we didn't know if damage had been done to the engine and if it would continue to run properly. The engine was not shut down; no parameters were exceeded (i.e. EGT). The engine was left at idle power and we executed a flaps 20 approach and landing as a precautionary step. The landing was uneventful. ARFF was on the scene.

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.