Narrative:

We departed rksi weighing about 618;000 pounds on the egoba 1L departure. The departure controller instructed us to fly the SID as published with restrictions; which was going to make crossing SI742 at FL170 difficult. Therefore I left the slats extended trying to climb to altitude; and also to out climb the 747 that took off before us as we hit his wake. In the end; we still had to advise the controller; we are unable SI742 at FL170. About 14;000 the international relief officer asked if I was aware that the slats were still extended; to which I replied; yes. Crossing about FL160; I called for slats retracted; thinking that I had enough speed protection (high and low) but I was very wrong as we got the stick shaker when retracting the slats. The stick shaker went on and off; I think 3 different times as I lowered the nose to gain airspeed. We only lost about 100-200 feet in the recovery. We continued with no further issues. We debriefed this as a crew and we all remembered doing this scenario a number of years ago in the simulator. I thought wrong thinking that it was affected at a higher altitude of around 23;000. Also; the international relief officer said in the debrief; 'that is why I asked if you were aware the slats were still extended.' if that was truly why he asked; I feel that he should have been more assertive and stated it much differently; though I was pilot flying and take full responsibility. I can assure you that I will not make this mistake again as I have been humbled and embarrassed but have learned from my mistake! Also; knowing that we were heavy; we needed to advise ATC that we will be unable to make the FL170 earlier and probably should have advised pre departure clearance controller.

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Original NASA ASRS Text

Title: MD-11 flight crew reported receiving a stick shaker when the Captain retracted the slats on departure from RKSI.

Narrative: We departed RKSI weighing about 618;000 pounds on the EGOBA 1L departure. The departure controller instructed us to fly the SID as published with restrictions; which was going to make crossing SI742 at FL170 difficult. Therefore I left the slats extended trying to climb to altitude; and also to out climb the 747 that took off before us as we hit his wake. In the end; we still had to advise the controller; we are unable SI742 at FL170. About 14;000 the IRO asked if I was aware that the slats were still extended; to which I replied; yes. Crossing about FL160; I called for slats retracted; thinking that I had enough speed protection (high and low) but I was very wrong as we got the stick shaker when retracting the slats. The stick shaker went on and off; I think 3 different times as I lowered the nose to gain airspeed. We only lost about 100-200 feet in the recovery. We continued with no further issues. We debriefed this as a crew and we all remembered doing this scenario a number of years ago in the simulator. I thought wrong thinking that it was affected at a higher altitude of around 23;000. Also; the IRO said in the debrief; 'that is why I asked if you were aware the slats were still extended.' If that was truly why he asked; I feel that he should have been more assertive and stated it much differently; though I was pilot flying and take full responsibility. I can assure you that I will not make this mistake again as I have been humbled and embarrassed but have learned from my mistake! Also; knowing that we were heavy; we needed to advise ATC that we will be unable to make the FL170 earlier and probably should have advised PDC controller.

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.