A319 crew inadvertently enters thunderstorm over arkansas at FL390.

Attributes
ACN	702857
Time
Date	200606
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : zme.artcc
State Reference	TN
Altitude	msl single value : 39000
Environment
Flight Conditions	IMC
Aircraft 1
Controlling Facilities	artcc : zme.artcc
Operator	common carrier : air carrier
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 240 flight time total : 10500 flight time type : 6200
ASRS Report	702857
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : turbulence inflight encounter : weather non adherence : published procedure non adherence : company policies non adherence : clearance other anomaly other anomaly
Independent Detector	aircraft equipment : altitude alert other flight crewa other flight crewb
Resolutory Action	controller : issued advisory flight crew : regained aircraft control flight crew : returned to assigned altitude flight crew : exited adverse environment
Supplementary
Problem Areas	Weather Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were in cruise at FL390 flying in a layer of cirrus clouds (IMC). WX radar was in use due to extensive isolated thunderstorms over texas; oklahoma; arkansas. A line of widely separated storms intersected our route of flight; none closer than 40-50 mi either side of our aircraft immediately prior to a turbulence encounter. We exited the cirrus layer and were met with a visual picture of a rapidly building storm immediately in front of us (nothing had been painted on radar leading up to the encounter). I could see the dome top rising rapidly in front of us and I reached up and turned on the fasten seatbelt sign followed by an announcement for the passenger to fasten their seatbelts. The captain mentioned that it was too late to avoid the storm and we ended up penetrating the top. Just as we began to enter the clouds; the aircraft began to climb rapidly and we began to experience what I would classify as moderate chop. In my opinion and understanding; we were literally riding the top of the storm as it pushed the aircraft upwards. My immediate concern was the altitude deviation as I saw the aircraft approaching FL400 and I made a call to center indicating our troubles associated with the storm. ATC replied that there was no other aircraft in our vicinity and asked if we needed any assistance. During the climb I heard the chimes associated with the autoplt being disconnected and also saw our airspeed hovering right at V maximum. I noticed the captain was hand flying and he informed me that he was doing his best to get the airplane back down to FL390. We probably experienced 0 G's for approximately 4-5 seconds and were then in light turbulence for a similar period. We eventually exited the storm cloud and returned to normal flight at FL390 within a min of the deviation. I notified ATC of the turbulence and building storm followed by a short announcement to the passenger explaining the reason for the turbulence. The captain called the flight attendants to inquire about their condition and was informed that all was ok and operations were normal. The captain and I agreed that although it was a precarious situation to find ourselves in; there was no further action required.

Original NASA ASRS Text

Title: A319 CREW INADVERTENTLY ENTERS TSTM OVER ARKANSAS AT FL390.

Narrative: WE WERE IN CRUISE AT FL390 FLYING IN A LAYER OF CIRRUS CLOUDS (IMC). WX RADAR WAS IN USE DUE TO EXTENSIVE ISOLATED TSTMS OVER TEXAS; OKLAHOMA; ARKANSAS. A LINE OF WIDELY SEPARATED STORMS INTERSECTED OUR RTE OF FLT; NONE CLOSER THAN 40-50 MI EITHER SIDE OF OUR ACFT IMMEDIATELY PRIOR TO A TURB ENCOUNTER. WE EXITED THE CIRRUS LAYER AND WERE MET WITH A VISUAL PICTURE OF A RAPIDLY BUILDING STORM IMMEDIATELY IN FRONT OF US (NOTHING HAD BEEN PAINTED ON RADAR LEADING UP TO THE ENCOUNTER). I COULD SEE THE DOME TOP RISING RAPIDLY IN FRONT OF US AND I REACHED UP AND TURNED ON THE FASTEN SEATBELT SIGN FOLLOWED BY AN ANNOUNCEMENT FOR THE PAX TO FASTEN THEIR SEATBELTS. THE CAPT MENTIONED THAT IT WAS TOO LATE TO AVOID THE STORM AND WE ENDED UP PENETRATING THE TOP. JUST AS WE BEGAN TO ENTER THE CLOUDS; THE ACFT BEGAN TO CLB RAPIDLY AND WE BEGAN TO EXPERIENCE WHAT I WOULD CLASSIFY AS MODERATE CHOP. IN MY OPINION AND UNDERSTANDING; WE WERE LITERALLY RIDING THE TOP OF THE STORM AS IT PUSHED THE ACFT UPWARDS. MY IMMEDIATE CONCERN WAS THE ALTDEV AS I SAW THE ACFT APCHING FL400 AND I MADE A CALL TO CTR INDICATING OUR TROUBLES ASSOCIATED WITH THE STORM. ATC REPLIED THAT THERE WAS NO OTHER ACFT IN OUR VICINITY AND ASKED IF WE NEEDED ANY ASSISTANCE. DURING THE CLB I HEARD THE CHIMES ASSOCIATED WITH THE AUTOPLT BEING DISCONNECTED AND ALSO SAW OUR AIRSPD HOVERING RIGHT AT V MAX. I NOTICED THE CAPT WAS HAND FLYING AND HE INFORMED ME THAT HE WAS DOING HIS BEST TO GET THE AIRPLANE BACK DOWN TO FL390. WE PROBABLY EXPERIENCED 0 G'S FOR APPROX 4-5 SECONDS AND WERE THEN IN LIGHT TURB FOR A SIMILAR PERIOD. WE EVENTUALLY EXITED THE STORM CLOUD AND RETURNED TO NORMAL FLT AT FL390 WITHIN A MIN OF THE DEV. I NOTIFIED ATC OF THE TURB AND BUILDING STORM FOLLOWED BY A SHORT ANNOUNCEMENT TO THE PAX EXPLAINING THE REASON FOR THE TURB. THE CAPT CALLED THE FLT ATTENDANTS TO INQUIRE ABOUT THEIR CONDITION AND WAS INFORMED THAT ALL WAS OK AND OPS WERE NORMAL. THE CAPT AND I AGREED THAT ALTHOUGH IT WAS A PRECARIOUS SITUATION TO FIND OURSELVES IN; THERE WAS NO FURTHER ACTION REQUIRED.

Data retrieved from NASA's ASRS site as of January 2009 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.