Air carrier widebody transport in-flight encounter with WX and strong downdraft.

Attributes
ACN	151929
Time
Date	199007
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : fak
State Reference	VA
Altitude	msl bound lower : 32300 msl bound upper : 33000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 200 flight time total : 20000 flight time type : 4000
ASRS Report	151929
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : weather other anomaly
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course flight crew : regained aircraft control
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

We were at 33000' in cruise when we entered an overcast. I had turned on the seat belt sign and was talking to the 'a' coordinator as to whether they should discontinue service. No rain cells were painted on radar in the clouds although there were cells painted 40-50 mi away. All of a sudden the vertical speed indicated showed 3000 FPM down. I stopped the descent after losing about 500-600'. We notified center that we were unable to hold 33000' and that we had deviations up to 700'. They turned me to a 90 degree heading and cleared me to 29000'. As I was turning to 90 degrees normal handling of aircraft returned and I advised center that I was now able to maintain 33000' and was cleared back on course and to maintain 33000'. During the entire tie, only light turbulence was present. We called a company flight that was approximately 50 mi ahead of us and asked if they had experienced the same thing. They said they had but did not mentioned it to anyone. We notified our metropolitan department as well as ATC as to what we experienced.

Original NASA ASRS Text

Title: ACR WDB INFLT ENCOUNTER WITH WX AND STRONG DOWNDRAFT.

Narrative: WE WERE AT 33000' IN CRUISE WHEN WE ENTERED AN OVCST. I HAD TURNED ON THE SEAT BELT SIGN AND WAS TALKING TO THE 'A' COORDINATOR AS TO WHETHER THEY SHOULD DISCONTINUE SVC. NO RAIN CELLS WERE PAINTED ON RADAR IN THE CLOUDS ALTHOUGH THERE WERE CELLS PAINTED 40-50 MI AWAY. ALL OF A SUDDEN THE VERT SPD INDICATED SHOWED 3000 FPM DOWN. I STOPPED THE DSNT AFTER LOSING ABOUT 500-600'. WE NOTIFIED CENTER THAT WE WERE UNABLE TO HOLD 33000' AND THAT WE HAD DEVIATIONS UP TO 700'. THEY TURNED ME TO A 90 DEG HDG AND CLRED ME TO 29000'. AS I WAS TURNING TO 90 DEGS NORMAL HANDLING OF ACFT RETURNED AND I ADVISED CENTER THAT I WAS NOW ABLE TO MAINTAIN 33000' AND WAS CLRED BACK ON COURSE AND TO MAINTAIN 33000'. DURING THE ENTIRE TIE, ONLY LIGHT TURB WAS PRESENT. WE CALLED A COMPANY FLT THAT WAS APPROX 50 MI AHEAD OF US AND ASKED IF THEY HAD EXPERIENCED THE SAME THING. THEY SAID THEY HAD BUT DID NOT MENTIONED IT TO ANYONE. WE NOTIFIED OUR METRO DEPT AS WELL AS ATC AS TO WHAT WE EXPERIENCED.

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.