 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
An airbus A320 flight crew had the overspd protection system climb the aircraft above the assigned altitude in turbulence near day, oh.
| Attributes | |
| ACN | 441625 |
| Time | |
| Date | 199907 |
| Day | Thu |
| Local Time Of Day | 0001 To 0600 |
| Place | |
| Locale Reference | navaid : ape.vortac |
| State Reference | OH |
| Altitude | msl bound lower : 37000 msl bound upper : 39000 |
| Environment | |
| Flight Conditions | IMC |
| Weather Elements | Turbulence Thunderstorm |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zob.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | A320 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other other vortac |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp pilot : cfi pilot : flight engineer |
| Experience | flight time last 90 days : 180 flight time total : 5200 flight time type : 220 |
| ASRS Report | 441625 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 250 flight time total : 19000 flight time type : 320 |
| ASRS Report | 441823 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter : turbulence inflight encounter : weather non adherence : clearance |
| Independent Detector | other flight crewa other flight crewb |
| Resolutory Action | aircraft : automation overrode flight crew flight crew : returned to assigned altitude |
| Supplementary | |
| Problem Areas | Weather FAA Aircraft |
| Primary Problem | Aircraft |
Narrative:
We were flying in cruise at FL370 at mach .80. There was continuous light chop and turbulence and convective activity, however, our radar was only showing level 1 activity 40 NM ahead. We were in IMC with the autoflt system engaged. All of a sudden, the airspeed jumped about 15 KTS up and we hit 2 severe jolts of turbulence and a strong updraft. I told the captain to watch the airspeed but before he could react it was well over the vmo. He got on the PA and told the flight attendants to be seated. At vmo +6 KTS, the airbus overspd protection system took over effectively locking us out. It reduced thrust to idle and pitched the nose up to decrease the speed. In about 15 seconds the speed had slowed and the captain regained control. We leveled at FL390, advised ATC of our situation, and descended to FL370. Fortunately the seat belt sign was on and no passenger were hurt. All 3 flight attendants had been thrown into the air, but none were hurt.
Original NASA ASRS Text
Title: AN AIRBUS A320 FLC HAD THE OVERSPD PROTECTION SYS CLB THE ACFT ABOVE THE ASSIGNED ALT IN TURB NEAR DAY, OH.
Narrative: WE WERE FLYING IN CRUISE AT FL370 AT MACH .80. THERE WAS CONTINUOUS LIGHT CHOP AND TURB AND CONVECTIVE ACTIVITY, HOWEVER, OUR RADAR WAS ONLY SHOWING LEVEL 1 ACTIVITY 40 NM AHEAD. WE WERE IN IMC WITH THE AUTOFLT SYS ENGAGED. ALL OF A SUDDEN, THE AIRSPD JUMPED ABOUT 15 KTS UP AND WE HIT 2 SEVERE JOLTS OF TURB AND A STRONG UPDRAFT. I TOLD THE CAPT TO WATCH THE AIRSPD BUT BEFORE HE COULD REACT IT WAS WELL OVER THE VMO. HE GOT ON THE PA AND TOLD THE FLT ATTENDANTS TO BE SEATED. AT VMO +6 KTS, THE AIRBUS OVERSPD PROTECTION SYS TOOK OVER EFFECTIVELY LOCKING US OUT. IT REDUCED THRUST TO IDLE AND PITCHED THE NOSE UP TO DECREASE THE SPD. IN ABOUT 15 SECONDS THE SPD HAD SLOWED AND THE CAPT REGAINED CTL. WE LEVELED AT FL390, ADVISED ATC OF OUR SIT, AND DSNDED TO FL370. FORTUNATELY THE SEAT BELT SIGN WAS ON AND NO PAX WERE HURT. ALL 3 FLT ATTENDANTS HAD BEEN THROWN INTO THE AIR, BUT NONE WERE HURT.
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.