A319 flight has airframe overspd during cruise flight.

Attributes
ACN	568683
Time
Date	200212
Day	Thu
Local Time Of Day	0001 To 0600
Place
Locale Reference	navaid : flm.vor
State Reference	KY
Altitude	msl bound lower : 32000 msl bound upper : 37500
Environment
Flight Conditions	VMC
Weather Elements	Windshear
Light	Night
Aircraft 1
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	A319
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : level
Route In Use	enroute airway : j134.airway
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 180 flight time total : 11700 flight time type : 796
ASRS Report	568683
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : overspeed warning other flight crewa other flight crewb
Resolutory Action	flight crew : regained aircraft control flight crew : overrode automation flight crew : exited adverse environment
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance Weather
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

At XA55Z, we were approximately 40 mi west of flm at FL370 and talking to ZID. The purser had just delivered the meals and the first officer had secured the door and was sitting down. The winds had been about 225 degrees at 125 KTS for a while. We encountered a rapidly decreasing tailwind diminishing to 225 degrees at 100 KTS over a very short span of time. The aircraft was on autoplt and mach .80 selected. I noticed a large trend arrow on the speed tape and immediately dialed down the mach number. The airspeed increased beyond vmo, the autoplt disconnected, and the airbus 'pull-up' began. I took control of the sidestick, selected idle thrust while the first officer thoughtfully deployed the speed brakes. Maximum speed attained was about vmo +10 KTS and we climbed to FL375 before regaining sidestick control to bring us down to our assigned altitude. There were no other aircraft on TCASII in our vicinity at FL390 and no ATC conflict occurred. Autoflt was re-engaged and maintenance notified of the overspd. We landed at iad without further incident. Lessons learned: the airbus overspd protection is not just commonly encountered near mountain wave, rapid jetstream shears can cause airspeed fluctuations sufficient to overspd the aircraft. The biggest clue on the fpf was the change in the tropopause from FL290 at stl to FL430 at flm. I'll pay as much attention to crossing frontal boundaries and jetstream gradients as I do when in an area of mountain wave.

Original NASA ASRS Text

Title: A319 FLT HAS AIRFRAME OVERSPD DURING CRUISE FLT.

Narrative: AT XA55Z, WE WERE APPROX 40 MI W OF FLM AT FL370 AND TALKING TO ZID. THE PURSER HAD JUST DELIVERED THE MEALS AND THE FO HAD SECURED THE DOOR AND WAS SITTING DOWN. THE WINDS HAD BEEN ABOUT 225 DEGS AT 125 KTS FOR A WHILE. WE ENCOUNTERED A RAPIDLY DECREASING TAILWIND DIMINISHING TO 225 DEGS AT 100 KTS OVER A VERY SHORT SPAN OF TIME. THE ACFT WAS ON AUTOPLT AND MACH .80 SELECTED. I NOTICED A LARGE TREND ARROW ON THE SPD TAPE AND IMMEDIATELY DIALED DOWN THE MACH NUMBER. THE AIRSPD INCREASED BEYOND VMO, THE AUTOPLT DISCONNECTED, AND THE AIRBUS 'PULL-UP' BEGAN. I TOOK CTL OF THE SIDESTICK, SELECTED IDLE THRUST WHILE THE FO THOUGHTFULLY DEPLOYED THE SPD BRAKES. MAX SPD ATTAINED WAS ABOUT VMO +10 KTS AND WE CLBED TO FL375 BEFORE REGAINING SIDESTICK CTL TO BRING US DOWN TO OUR ASSIGNED ALT. THERE WERE NO OTHER ACFT ON TCASII IN OUR VICINITY AT FL390 AND NO ATC CONFLICT OCCURRED. AUTOFLT WAS RE-ENGAGED AND MAINT NOTIFIED OF THE OVERSPD. WE LANDED AT IAD WITHOUT FURTHER INCIDENT. LESSONS LEARNED: THE AIRBUS OVERSPD PROTECTION IS NOT JUST COMMONLY ENCOUNTERED NEAR MOUNTAIN WAVE, RAPID JETSTREAM SHEARS CAN CAUSE AIRSPD FLUCTUATIONS SUFFICIENT TO OVERSPD THE ACFT. THE BIGGEST CLUE ON THE FPF WAS THE CHANGE IN THE TROPOPAUSE FROM FL290 AT STL TO FL430 AT FLM. I'LL PAY AS MUCH ATTN TO XING FRONTAL BOUNDARIES AND JETSTREAM GRADIENTS AS I DO WHEN IN AN AREA OF MOUNTAIN WAVE.

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.