Narrative:

I was the pilot flying on this flight we took-off and were flying the departure. We started to clean-up at 3;000 ft AGL and commenced an approximate 60 degree right hand turn for the SID. We were cleared to 6;000 ft as per the SID. I was hand-flying the aircraft during the departure and throttles were being commanded with auto-throttle. About this same time; the plane entered IMC with choppy ride conditions. During the last part of the turn; as we were rolling out; flaps were retracted to zero. It was at this point; as we were climbing to 6;000; in choppy ride conditions; that we encountered a stick shaker warning. I immediately lowered the nose; power was advanced; and the warning ceased. As power was advanced; it was then that we discovered the right engine RPM had rolled back in an apparent compressor stall. As per the checklist; the right thrust lever was immediately retarded to idle as the left thrust lever was advanced to save airspeed. We tried advancing the right thrust lever after a short wait but encountered a secondary compressor stall after moving the thrust lever only a small amount. Once again; the right thrust lever was retarded back to idle. During the troubleshooting process for the compressor stall and then trying to fly a very heavy; performance limited aircraft on a single engine; our altitude varied slightly between 4;800 ft and 5;300 ft on the SID. We subsequently declared an emergency with departure control and elected to remain at 5;000 ft for our return for an overweight landing. Approach control vectored us around for our arrival and ILS approach. We completed our emergency checklists; dumped a slight amount of fuel (with approval from approach control) and conducted an ILS approach. During the vectoring for our arrival; we tried advancing the right thrust lever one more time; and this time; power came back normally. We subsequently landed with both engines working normally. Landing and taxi-in were normal and uneventful. Continue to emphasize engine failures/compressor stalls not only immediately after take-off but also in a turn and in the weather during training. This type of failure is very insidious and potentially dangerous.

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Original NASA ASRS Text

Title: B767 flight crew experiences an engine rollback climbing out of 5;000 FT that result in a large yaw angle and a momentary stick shaker. The thrust lever for the affected engine is brought to idle and attempts to increase thrust are not successful. An emergency is declared; some fuel is dumped and the flight returns to the departure airport. While being vectored for approach the thrust lever is advanced again and the engine responds normally.

Narrative: I was the pilot flying on this Flight We took-off and were flying the departure. We started to clean-up at 3;000 FT AGL and commenced an approximate 60 degree right hand turn for the SID. We were cleared to 6;000 FT as per the SID. I was hand-flying the aircraft during the departure and throttles were being commanded with auto-throttle. About this same time; the plane entered IMC with choppy ride conditions. During the last part of the turn; as we were rolling out; flaps were retracted to zero. It was at this point; as we were climbing to 6;000; in choppy ride conditions; that we encountered a stick shaker warning. I immediately lowered the nose; power was advanced; and the warning ceased. As power was advanced; it was then that we discovered the right engine RPM had rolled back in an apparent compressor stall. As per the checklist; the right thrust lever was immediately retarded to idle as the left thrust lever was advanced to save airspeed. We tried advancing the right thrust lever after a short wait but encountered a secondary compressor stall after moving the thrust lever only a small amount. Once again; the right thrust lever was retarded back to idle. During the troubleshooting process for the compressor stall and then trying to fly a very heavy; performance limited aircraft on a single engine; our altitude varied slightly between 4;800 FT and 5;300 FT on the SID. We subsequently declared an emergency with Departure Control and elected to remain at 5;000 FT for our return for an overweight landing. Approach Control vectored us around for our arrival and ILS approach. We completed our emergency checklists; dumped a slight amount of fuel (with approval from Approach Control) and conducted an ILS approach. During the vectoring for our arrival; we tried advancing the right thrust lever one more time; and this time; power came back normally. We subsequently landed with both engines working normally. Landing and taxi-in were normal and uneventful. Continue to emphasize engine failures/compressor stalls not only immediately after take-off but also in a turn and in the weather during training. This type of failure is very insidious and potentially dangerous.

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.