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|
Attributes | |
ACN | 749731 |
Time | |
Date | 200708 |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | VMC |
Weather Elements | other |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | A321 |
Operating Under FAR Part | Part 121 |
Flight Phase | ground : takeoff roll |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
ASRS Report | 749731 |
Events | |
Anomaly | aircraft equipment problem : critical |
Independent Detector | other flight crewa |
Resolutory Action | flight crew : took precautionary avoidance action |
Consequence | other |
Supplementary | |
Problem Areas | Aircraft Weather |
Primary Problem | Aircraft |
Narrative:
This was now delayed flight after we had just had an air abort approximately 6 hours earlier in the same aircraft for a flight control malfunction. Heavy rain associated with convective activity directly over the airport as we were awaiting flight closeout. WX moved to the south and rain dissipating as we taxied to runway 18R. We were #4 in line for departure listening to tower issue windshear alerts for runway 18L. The wind was still gusting out of the nnw; but was settling and shifting further to the west as it became our turn to take the runway. The first officer and I both agreed to a toga setting for takeoff even though there were no windshear alerts for runway 18R although winds very variable between center field wind and runway 18R departure end winds. As we took the runway; I requested a wind check and was told 310 degrees/9 KTS. The radar was depicting a cell about 1.5 mi and slightly left of runway 18R centerline. The last 3 departures did not report any windshear or airspeed fluctuations on takeoff or departure. The first officer selected toga power and I confirmed it and scanned the engine instruments and went to the airspeed indicator. It remained at zero as we began to accelerate and I began to call an airspeed stagnation which I assumed was related to a potential windshear event occurring. Went back to the engine instruments and returned to my airspeed indicator which remained at zero. At that time; I asked the first officer if he had airspeed indications and he said yes. I rejected the takeoff not knowing what our airspeed was at the time; but knowing that I had an airspeed indicator failure without any warning flags or ECAM advisory or warnings. The first officer said that we aborted between 100-120 KTS. Returned to the gate. First officer handled ATC; flight attendant; passenger and company communication. Maintenance met us at the gate and told me it could have been from trapped water in the pitot tube unable to drain from the previous heavy rain encounter prior to taxi out for takeoff. I have never heard of such a thing in my yrs of flying. I have heard of a blocked pitot tube or static port; but never of heavy rain creating such a situation especially with heated probes.
Original NASA ASRS Text
Title: A320 REJECTS TKOF DURING INCLEMENT WX DUE TO FAILURE OF CAPTAIN'S ASI. MAINT SUSPECTS WATER IN PITOT SYSTEM FROM HEAVY PRECIPITATION.
Narrative: THIS WAS NOW DELAYED FLT AFTER WE HAD JUST HAD AN AIR ABORT APPROX 6 HRS EARLIER IN THE SAME ACFT FOR A FLT CTL MALFUNCTION. HVY RAIN ASSOCIATED WITH CONVECTIVE ACTIVITY DIRECTLY OVER THE ARPT AS WE WERE AWAITING FLT CLOSEOUT. WX MOVED TO THE S AND RAIN DISSIPATING AS WE TAXIED TO RWY 18R. WE WERE #4 IN LINE FOR DEP LISTENING TO TWR ISSUE WINDSHEAR ALERTS FOR RWY 18L. THE WIND WAS STILL GUSTING OUT OF THE NNW; BUT WAS SETTLING AND SHIFTING FURTHER TO THE W AS IT BECAME OUR TURN TO TAKE THE RWY. THE FO AND I BOTH AGREED TO A TOGA SETTING FOR TKOF EVEN THOUGH THERE WERE NO WINDSHEAR ALERTS FOR RWY 18R ALTHOUGH WINDS VERY VARIABLE BTWN CTR FIELD WIND AND RWY 18R DEP END WINDS. AS WE TOOK THE RWY; I REQUESTED A WIND CHK AND WAS TOLD 310 DEGS/9 KTS. THE RADAR WAS DEPICTING A CELL ABOUT 1.5 MI AND SLIGHTLY L OF RWY 18R CTRLINE. THE LAST 3 DEPS DID NOT RPT ANY WINDSHEAR OR AIRSPD FLUCTUATIONS ON TKOF OR DEP. THE FO SELECTED TOGA PWR AND I CONFIRMED IT AND SCANNED THE ENG INSTS AND WENT TO THE AIRSPD INDICATOR. IT REMAINED AT ZERO AS WE BEGAN TO ACCELERATE AND I BEGAN TO CALL AN AIRSPD STAGNATION WHICH I ASSUMED WAS RELATED TO A POTENTIAL WINDSHEAR EVENT OCCURRING. WENT BACK TO THE ENG INSTS AND RETURNED TO MY AIRSPD INDICATOR WHICH REMAINED AT ZERO. AT THAT TIME; I ASKED THE FO IF HE HAD AIRSPD INDICATIONS AND HE SAID YES. I REJECTED THE TKOF NOT KNOWING WHAT OUR AIRSPD WAS AT THE TIME; BUT KNOWING THAT I HAD AN AIRSPD INDICATOR FAILURE WITHOUT ANY WARNING FLAGS OR ECAM ADVISORY OR WARNINGS. THE FO SAID THAT WE ABORTED BTWN 100-120 KTS. RETURNED TO THE GATE. FO HANDLED ATC; FLT ATTENDANT; PAX AND COMPANY COM. MAINT MET US AT THE GATE AND TOLD ME IT COULD HAVE BEEN FROM TRAPPED WATER IN THE PITOT TUBE UNABLE TO DRAIN FROM THE PREVIOUS HVY RAIN ENCOUNTER PRIOR TO TAXI OUT FOR TKOF. I HAVE NEVER HEARD OF SUCH A THING IN MY YRS OF FLYING. I HAVE HEARD OF A BLOCKED PITOT TUBE OR STATIC PORT; BUT NEVER OF HVY RAIN CREATING SUCH A SITUATION ESPECIALLY WITH HEATED PROBES.
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.