High level wind shear encounter. Temporary loss of aircraft control.

Attributes
ACN	294480
Time
Date	199501
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : msy
State Reference	LA
Altitude	msl bound lower : 36400 msl bound upper : 37400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zhu
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 225 flight time total : 20000 flight time type : 18000
ASRS Report	294480
Person 2
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : instrument pilot : atp pilot : commercial pilot : flight engineer
Experience	flight time last 90 days : 200 flight time total : 5000 flight time type : 1700
ASRS Report	294483
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter other non adherence : clearance other anomaly
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : exited adverse environment flight crew : regained aircraft control
Consequence	faa : reviewed incident with flight crew Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

A fast moving cold front was just passing out of the dfw- txk-act area moving in a southeast direction extending along tx, ark, la areas. We picked our way around the front coming in from the back side on our way to mia. As we leveled off at FL370, no storms were above us and we could see the line below us with most of the activity to our right. We were vectored toward lfk and then to proceed over msy and out over the gulf to mia. At about the 295R from msy at about 210 mi from msy, the aircraft suddenly, with autoplt on, swung into a 35-45 degrees right bank, lost 600-700 ft altitude and our airspeed dropped from 280-290 KIAS to 205 KIAS all in less than 5 seconds. We heard stall buffet going over our wings for at least 20-30 seconds. The aircraft pitched up to a plus 400 ft over FL370, airspeed would not recover and bank was still oscillating back and forth about 15-20 degrees. We immediately requested lower, were given FL330 and as we descended, aircraft's stability returned. No passenger nor flight attendants were injured at any time. I had sat everyone down well before we encountered this situation. I notified ATC and dispatch. Other aircraft especially one at FL410 reported similar problems. The rest of the flight was uneventful. I feel that with this cold front hitting the warm moist gulf air, we experienced high altitude wind shear. Supplemental information from acn 294483: we notified ATC and operations to insure other aircraft would avoid the area we had encountered high altitude wind shear indications.

Original NASA ASRS Text

Title: HIGH LEVEL WIND SHEAR ENCOUNTER. TEMPORARY LOSS OF ACFT CTL.

Narrative: A FAST MOVING COLD FRONT WAS JUST PASSING OUT OF THE DFW- TXK-ACT AREA MOVING IN A SE DIRECTION EXTENDING ALONG TX, ARK, LA AREAS. WE PICKED OUR WAY AROUND THE FRONT COMING IN FROM THE BACK SIDE ON OUR WAY TO MIA. AS WE LEVELED OFF AT FL370, NO STORMS WERE ABOVE US AND WE COULD SEE THE LINE BELOW US WITH MOST OF THE ACTIVITY TO OUR R. WE WERE VECTORED TOWARD LFK AND THEN TO PROCEED OVER MSY AND OUT OVER THE GULF TO MIA. AT ABOUT THE 295R FROM MSY AT ABOUT 210 MI FROM MSY, THE ACFT SUDDENLY, WITH AUTOPLT ON, SWUNG INTO A 35-45 DEGS R BANK, LOST 600-700 FT ALT AND OUR AIRSPD DROPPED FROM 280-290 KIAS TO 205 KIAS ALL IN LESS THAN 5 SECONDS. WE HEARD STALL BUFFET GOING OVER OUR WINGS FOR AT LEAST 20-30 SECONDS. THE ACFT PITCHED UP TO A PLUS 400 FT OVER FL370, AIRSPD WOULD NOT RECOVER AND BANK WAS STILL OSCILLATING BACK AND FORTH ABOUT 15-20 DEGS. WE IMMEDIATELY REQUESTED LOWER, WERE GIVEN FL330 AND AS WE DSNDED, ACFT'S STABILITY RETURNED. NO PAX NOR FLT ATTENDANTS WERE INJURED AT ANY TIME. I HAD SAT EVERYONE DOWN WELL BEFORE WE ENCOUNTERED THIS SIT. I NOTIFIED ATC AND DISPATCH. OTHER ACFT ESPECIALLY ONE AT FL410 RPTED SIMILAR PROBS. THE REST OF THE FLT WAS UNEVENTFUL. I FEEL THAT WITH THIS COLD FRONT HITTING THE WARM MOIST GULF AIR, WE EXPERIENCED HIGH ALT WIND SHEAR. SUPPLEMENTAL INFO FROM ACN 294483: WE NOTIFIED ATC AND OPS TO INSURE OTHER ACFT WOULD AVOID THE AREA WE HAD ENCOUNTERED HIGH ALT WIND SHEAR INDICATIONS.

Data retrieved from NASA's ASRS site as of July 2007 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.