Narrative:

We had approximately 100 KTS of headwind going towards las. When I slowed down to 10 KTS over amber footer; I took away an important safety net. When we turned out of the wind; the headwind component decreased rapidly and the engines couldn't keep up with the airspeed loss. Contributing factors were the slower speed I was intentionally initially at; the FMC having selected a right turn instead of a left turn; my not catching the right turn indicated before executing it. Also; when I selected heading select to turn left; the bank angle limiter was on 30 degrees. The extra g-loading this bank angle caused was a secondary factor in the accelerated stall. The 100 KT headwind turning into a 100 KT tailwind combined with my slower than normal selected speed was the biggest factor in my opinion. We took a ground delay coming out of mke due to a left forward window heat overheat annunciation. Maintenance found a circuit breaker popped; the 'window heat power left front' circuit breaker on panel P6-11 row B. The breaker was reset and return-to-service tests were normal. We left the gate 45 minutes behind schedule. Just past des moines; ia; we heard a circuit breaker pop and the master caution light came on. It was the same circuit breaker as before. We performed the QRH checklist. I then contacted dispatch via ACARS to tell them about the recurring problem. The first communication we received back from dispatch was to tell us that we were probably going to return to mke for maintenance. At this point I slowed the aircraft to approximately 10 KTS over the amber footer; so we wouldn't be speeding away from our probable landing airport. After dispatch confirmed we were to return to mke; we contacted ATC and requested to return to mke. We were issued a left turn direct jvl. When this was inserted; I didn't pay enough attention to the direction of the turn; and the aircraft began a right turn; as was executed in the FMC. I immediately noticed the aircraft was turning the wrong way and pushed heading select and began a left turn to comply with the ATC clearance. A very short time later; the stall warning alert came on; and I noticed some slight buffeting. I performed the stall recovery procedure; rolling wings level and setting max power. We had completed about 90 degrees of the turn; so we were perpendicular to our original and return course after correction. I selected VNAV to return to normal speed; and after acceleration to normal speed we resumed our left turn direct jvl. We did not lose altitude nor directional control or stability at any time. The stall warning and buffeting lasted between 5-10 seconds in my estimation. No engine exceedences were noted. I had not personally ever experienced that drastic an airspeed change in such a short amount of time. In hindsight; of course I am kicking myself for not anticipating the airspeed change when going from a headwind to a tailwind. The only suggestion I have as far as modifications to the aircraft would be to install automated bank angle limiters in the 737; as we have in the 717. This might have prevented the accelerated stall and also slowed the turn rate so that the airspeed changes would have not been so severe as to overwhelm the engines. The bottom line is; it was my fault. I didn't monitor the airplane well enough.

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Original NASA ASRS Text

Title: After slowing in anticipation of returning to the departure airport; a B737-700 encountered a stick shaker and aerodynamic buffeting while reversing course at altitude.

Narrative: We had approximately 100 KTS of headwind going towards LAS. When I slowed down to 10 KTS over amber footer; I took away an important safety net. When we turned out of the wind; the headwind component decreased rapidly and the engines couldn't keep up with the airspeed loss. Contributing factors were the slower speed I was intentionally initially at; the FMC having selected a right turn instead of a left turn; my not catching the right turn indicated before executing it. Also; when I selected Heading Select to turn left; the bank angle limiter was on 30 degrees. The extra g-loading this bank angle caused was a secondary factor in the accelerated stall. The 100 KT headwind turning into a 100 KT tailwind combined with my slower than normal selected speed was the biggest factor in my opinion. We took a ground delay coming out of MKE due to a left forward window heat overheat annunciation. Maintenance found a circuit breaker popped; the 'Window Heat Power Left Front' circuit breaker on panel P6-11 row B. The breaker was reset and return-to-service tests were normal. We left the gate 45 minutes behind schedule. Just past Des Moines; IA; we heard a circuit breaker pop and the master caution light came on. It was the same circuit breaker as before. We performed the QRH checklist. I then contacted Dispatch via ACARS to tell them about the recurring problem. The first communication we received back from Dispatch was to tell us that we were probably going to return to MKE for maintenance. At this point I slowed the aircraft to approximately 10 KTS over the amber footer; so we wouldn't be speeding away from our probable landing airport. After Dispatch confirmed we were to return to MKE; we contacted ATC and requested to return to MKE. We were issued a left turn direct JVL. When this was inserted; I didn't pay enough attention to the direction of the turn; and the aircraft began a right turn; as was executed in the FMC. I immediately noticed the aircraft was turning the wrong way and pushed Heading Select and began a left turn to comply with the ATC clearance. A very short time later; the stall warning alert came on; and I noticed some slight buffeting. I performed the stall recovery procedure; rolling wings level and setting max power. We had completed about 90 degrees of the turn; so we were perpendicular to our original and return course after correction. I selected VNAV to return to normal speed; and after acceleration to normal speed we resumed our left turn direct JVL. We did not lose altitude nor directional control or stability at any time. The stall warning and buffeting lasted between 5-10 seconds in my estimation. No engine exceedences were noted. I had not personally ever experienced that drastic an airspeed change in such a short amount of time. In hindsight; of course I am kicking myself for not anticipating the airspeed change when going from a headwind to a tailwind. The only suggestion I have as far as modifications to the aircraft would be to install automated bank angle limiters in the 737; as we have in the 717. This might have prevented the accelerated stall and also slowed the turn rate so that the airspeed changes would have not been so severe as to overwhelm the engines. The bottom line is; it was my fault. I didn't monitor the airplane well enough.

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.