Narrative:

We were in cruise flight at FL390. My first officer and I began to brief the approach in to our destination. ATC assigned us an airspeed reduction to mach .76. We continued briefing the details of the arrival and taxi-in. Soon we both looked at the airspeed of the aircraft and noticed it was well below our assigned speed of .76. The first officer; the pilot flying; pushed the power up to maximum continuous thrust based on the continued deterioration of airspeed. I; as the captain; quickly concluded an immediate descent was necessary because the airspeed was not stabilizing. I requested FL370 from ATC. We were assigned FL370 and we descended. In this very short time frame the autopilot disconnected and we received a momentary stick shaker. My first officer using his training excellently pitched the nose of the aircraft forward and we regained our airspeed. We leveled at FL370 and reduced thrust with sufficient airspeed. There was no further incident. There were three primary factors for why this occurred. First we were assigned a reduced airspeed. This initiated the event. Second was the rate at which the airspeed decreased was more then anticipated. The amount of thrust reduction could have affected this. However; I don't recall a large thrust lever movement. My first officer; in our debrief; indicated that the amount of thrust lever movement at altitude is much less then at a lower altitude. Finally the fact that both the first officer and I had our eyes looking at the chart for our approach planning this created an obvious distraction. We utilized our training and executed an immediate advance of thrust to maximum continuous thrust. We then changed the pitch of the aircraft to regain performance at FL390. This event can be avoided by better recognizing the small window of performance limitations the aircraft has while operating at FL390. Additionally the pilot flying and pilot not flying should always keep briefings managed by monitoring the flight instruments continuously during the briefing. That is the pilot flying should look away only momentarily only enough to verify required briefing items. Finally as the captain it is completely my responsibility to manage the tasks at hand to continuously monitor the aircraft while performing other duties.

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Original NASA ASRS Text

Title: A CRJ700 crew was assigned a speed reduction at FL390 while conducting the arrival briefing and subsequently the aircraft slowed so that the autopilot disconnected; the stick shaker momentarily activated and recovery was made with maximum continuous thrust power descending to FL370.

Narrative: We were in cruise flight at FL390. My First Officer and I began to brief the approach in to our destination. ATC assigned us an airspeed reduction to Mach .76. We continued briefing the details of the arrival and taxi-in. Soon we both looked at the airspeed of the aircraft and noticed it was well below our assigned speed of .76. The First Officer; the pilot flying; pushed the power up to maximum continuous thrust based on the continued deterioration of airspeed. I; as the Captain; quickly concluded an immediate descent was necessary because the airspeed was not stabilizing. I requested FL370 from ATC. We were assigned FL370 and we descended. In this very short time frame the autopilot disconnected and we received a momentary stick shaker. My First Officer using his training excellently pitched the nose of the aircraft forward and we regained our airspeed. We leveled at FL370 and reduced thrust with sufficient airspeed. There was no further incident. There were three primary factors for why this occurred. First we were assigned a reduced airspeed. This initiated the event. Second was the rate at which the airspeed decreased was more then anticipated. The amount of thrust reduction could have affected this. However; I don't recall a large thrust lever movement. My First Officer; in our debrief; indicated that the amount of thrust lever movement at altitude is much less then at a lower altitude. Finally the fact that both the First Officer and I had our eyes looking at the chart for our approach planning this created an obvious distraction. We utilized our training and executed an immediate advance of thrust to maximum continuous thrust. We then changed the pitch of the aircraft to regain performance at FL390. This event can be avoided by better recognizing the small window of performance limitations the aircraft has while operating at FL390. Additionally the pilot flying and pilot not flying should always keep briefings managed by monitoring the flight instruments continuously during the briefing. That is the pilot flying should look away only momentarily only enough to verify required briefing items. Finally as the Captain it is completely my responsibility to manage the tasks at hand to continuously monitor the aircraft while performing other duties.

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.