Narrative:

Center informed us that our destination was temporarily closed with a power outage and we were to expect 30 minutes holding in about 100 miles at FL380. We were around 800 miles from [destaination]. The controller suggested we slow down immediately to minimize our time in holding. Speed was at our discretion and he said that he was going to be slowing others down behind us as well. We checked the suggested holding speed at FL380; informed ATC of our intended speed which was approved and we started slowing down. The weather was clear and there was no turbulence. The autopilot and autothrottles were engaged. We informed the flight attendants of possible holding as well as an arrival delay and told the purser we would not tell the passenger until right before entering the hold. After slowing down; we started to look at our options to determine how long we could hold; and possible divert locations. I wanted to start developing a plan for when we received holding instructions. About 10 minutes later with no warning; the airspeed dropped about 15 knots and was still decreasing. There was no advance warning from the airplane and neither of us felt any turbulence or updraft sensation. Our pitch was already much higher than normal because ATC had us slow down. I added power to maximum but the nose continued to pitch up and the airspeed continued to decrease. I tried to recover with the autopilot on as the flight manual says; however; the prescribed five degrees of pitch and maximum thrust did not work to recover the airplane. I was able to finally push the nose down enough and get the airspeed loss to stop. I lost approximately 200 feet before recovering the airplane and getting the airspeed to start to slowly increase. Shortly thereafter; center switched us over to the next controller. The first officer checked in and told him of our new speed we were maintaining. Since we had gone about 100 miles; I had the first officer ask the ATC controller when we should expect our holding instructions. The controller stated he didn't know anything about holding instructions or [our destination] having any ATC delays. After a short discussion; the new controller told us we could resume normal speed. I remember several more aircraft behind us checking in after we did who were also slowed down and were now increasing their speed. They too had encountered the same unexpected mountain wave. Somewhere in all the confusion trying to regain control of the aircraft and trying to figure out what happened; I remember ATC announced to all aircraft there was mountain wave activity over the abcd mountains. This was the first we had heard about it or had any indications the possibility for mountain wave existed. This helped us account for what possibly happened; but we both remarked that in all our previous mountain wave encounters; you could feel the airplane rising. Neither one of us felt anything out of the ordinary when the speed suddenly decayed. It also appeared that the 757 had gotten behind the power curve while the autopilot held level flight and the aircraft speed kept decreasing with maximum power. The airplane was heading for a full stall very quickly. During the stall recovery; I tried to follow what I remembered reading about the new stall recovery procedures and guidance published in our new flight manual. This guidance tells us to hold altitude and minimize altitude loss. It also tells us to leave the airplane on the autopilot. These steps made the recovery worse. The new stall procedures are different from what I had been previously taught during our simulator training prior to our merger. The new stall procedures in our flight manual were not trained in any of our merger phases.after going back and reading the new stall procedures again in the book; the procedures are confusing; contradictory; and unclear. New full stall recovery procedures were also added to the flight manual which the company stillhasn't trained. The situation became more unsafe and the recovery was delayed because it was the first time I had tried the new procedures and I confused them with the old procedures. This was probably due to the fact that I had never practiced the new procedures in a simulator. Trying to teach myself new emergency recovery procedures and develop skills by simply reading a book without any classroom training from an instructor or simulator training did not work. If it had not been for my previous military training in aerodynamics and stall recoveries; I think we may have lost control of the airplane. This accident chain of events started with new stall procedures and guidance being published for the 757; for which I received inadequate training. The next link in the chain occurred when the ATC controller started slowing all the aircraft down at cruise because [our destination] was closed; yet the next controller knew nothing about any delays. Next link; we encountered an unexpected mountain wave that gave us an unexpected 15+ knot loss of airspeed that the automation could not control. The final link was the confusion between the old 'ingrained by repeated training' skills and the new untrained procedures which delayed the recovery.

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Original NASA ASRS Text

Title: A B757-200 flight crew; slowed at FL380 by ATC to minimize holding; suffered an approach to stall when they encountered mountain wave over mountains. Their attempts to recover using newly established stall recovery techniques for which they had received no hands on training; proved inadequate and they were forced to intervene falling back on old; long ingrained; techniques.

Narrative: Center informed us that our destination was temporarily closed with a power outage and we were to expect 30 minutes holding in about 100 miles at FL380. We were around 800 miles from [destaination]. The controller suggested we slow down immediately to minimize our time in holding. Speed was at our discretion and he said that he was going to be slowing others down behind us as well. We checked the suggested holding speed at FL380; informed ATC of our intended speed which was approved and we started slowing down. The weather was clear and there was no turbulence. The autopilot and autothrottles were engaged. We informed the Flight Attendants of possible holding as well as an arrival delay and told the purser we would not tell the PAX until right before entering the hold. After slowing down; we started to look at our options to determine how long we could hold; and possible divert locations. I wanted to start developing a plan for when we received holding instructions. About 10 minutes later with no warning; the airspeed dropped about 15 knots and was still decreasing. There was no advance warning from the airplane and neither of us felt any turbulence or updraft sensation. Our pitch was already much higher than normal because ATC had us slow down. I added power to MAX but the nose continued to pitch up and the airspeed continued to decrease. I tried to recover with the autopilot on as the flight manual says; however; the prescribed five degrees of pitch and MAX thrust did not work to recover the airplane. I was able to finally push the nose down enough and get the airspeed loss to stop. I lost approximately 200 feet before recovering the airplane and getting the airspeed to start to slowly increase. Shortly thereafter; Center switched us over to the next controller. The First Officer checked in and told him of our new speed we were maintaining. Since we had gone about 100 miles; I had the First Officer ask the ATC controller when we should expect our holding instructions. The controller stated he didn't know anything about holding instructions or [our destination] having any ATC delays. After a short discussion; the new controller told us we could resume normal speed. I remember several more aircraft behind us checking in after we did who were also slowed down and were now increasing their speed. They too had encountered the same unexpected mountain wave. Somewhere in all the confusion trying to regain control of the aircraft and trying to figure out what happened; I remember ATC announced to all aircraft there was mountain wave activity over the ABCD mountains. This was the first we had heard about it or had any indications the possibility for mountain wave existed. This helped us account for what possibly happened; but we both remarked that in all our previous mountain wave encounters; you could feel the airplane rising. Neither one of us felt anything out of the ordinary when the speed suddenly decayed. It also appeared that the 757 had gotten behind the power curve while the autopilot held level flight and the aircraft speed kept decreasing with MAX power. The airplane was heading for a full stall very quickly. During the stall recovery; I tried to follow what I remembered reading about the new stall recovery procedures and guidance published in our new Flight Manual. This guidance tells us to hold altitude and minimize altitude loss. It also tells us to leave the airplane on the autopilot. These steps made the recovery worse. The new stall procedures are different from what I had been previously taught during our simulator training prior to our merger. The new stall procedures in our Flight Manual were not trained in any of our merger phases.After going back and reading the new stall procedures again in the book; the procedures are confusing; contradictory; and unclear. New full stall recovery procedures were also added to the Flight Manual which the company stillhasn't trained. The situation became more unsafe and the recovery was delayed because it was the first time I had tried the new procedures and I confused them with the old procedures. This was probably due to the fact that I had never practiced the new procedures in a simulator. Trying to teach myself new emergency recovery procedures and develop skills by simply reading a book without any classroom training from an instructor or simulator training did not work. If it had not been for my previous military training in aerodynamics and stall recoveries; I think we may have lost control of the airplane. This accident chain of events started with new stall procedures and guidance being published for the 757; for which I received inadequate training. The next link in the chain occurred when the ATC controller started slowing all the aircraft down at cruise because [our destination] was closed; yet the next controller knew nothing about any delays. Next link; we encountered an unexpected mountain wave that gave us an unexpected 15+ knot loss of airspeed that the automation could not control. The final link was the confusion between the old 'ingrained by repeated training' skills and the new untrained procedures which delayed the recovery.

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.