After experiencing a negative wind shear at fl 350 an MD88 was unable to regain airspeed or maintain...

Attributes
ACN	845728
Time
Date	200907
Place
Locale Reference	ZAB.ARTCC
State Reference	NM
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	MD-88
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Air Traffic Control Military 7 Air Traffic Control Non Radar 2 Air Traffic Control Radar 28 Air Traffic Control Supervisory 2 Flight Crew Last 90 Days 150 Flight Crew Total 13000 Flight Crew Type 5000
Events
Anomaly	Deviation - Speed All Types Inflight Event / Encounter Weather / Turbulence Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

While avoiding thunderstorms over amarillo; we found ourselves going around build ups in the area at fl 350. Passing one build up we found the wind to be 25k off our right side. As we came around it and began avoiding another build up; it became quiet. We felt we were maybe in a transition area and were alerted by it. As we maneuvered by radar; it was dark; we found that it was getting harder for the airplane to hold altitude. We looked down at the airspeed and we had suddenly lost 50 knots. The winds had changed to a tailwind suddenly; removing those 50 knots and putting the airplane behind the power curve. At full climb power; even max continuous; we could no longer hold altitude nor accelerate and we asked ATC for clearance lower. The autopilot disconnected when it could not hold altitude; so we manually took control. We descended to fl 330; finally stabilizing the aircraft and leveling off. In the process we were right at the cusp of the buffet; which sounded very unusual to the flight attendants and the passengers. No unusual maneuvers were needed; so we simply brought the airplane in for a normal landing and did not mention anything that had happened to the passengers.

Original NASA ASRS Text

Title: After experiencing a negative wind shear at FL 350 an MD88 was unable to regain airspeed or maintain altitude and the flight crew had to descend to regain dynamic control.

Narrative: While avoiding thunderstorms over Amarillo; we found ourselves going around build ups in the area at FL 350. Passing one build up we found the wind to be 25k off our right side. As we came around it and began avoiding another build up; it became quiet. We felt we were maybe in a transition area and were alerted by it. As we maneuvered by radar; it was dark; we found that it was getting harder for the airplane to hold altitude. We looked down at the airspeed and we had suddenly lost 50 knots. The winds had changed to a tailwind suddenly; removing those 50 knots and putting the airplane behind the power curve. At full climb power; even max continuous; we could no longer hold altitude nor accelerate and we asked ATC for clearance lower. The autopilot disconnected when it could not hold altitude; so we manually took control. We descended to FL 330; finally stabilizing the aircraft and leveling off. In the process we were right at the cusp of the buffet; which sounded very unusual to the flight attendants and the passengers. No unusual maneuvers were needed; so we simply brought the airplane in for a normal landing and did not mention anything that had happened to the passengers.

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.

After experiencing a negative wind shear at fl 350 an MD88 was unable to regain airspeed or maintain altitude and the flight crew had to descend to regain dynamic control.