Wednesday, June 3, 2009

Avoid Airbus A330/A340 until this is resolved.

http://tinyurl.com/ght5lc
A Past Flight May Offer Clues to Air France 447 By MARK THOMPSON, WASHINGTON
We'll never know ...Air France Flight 447 as it plunged into the Atlantic Ocean on May 31, apparently killing all 228 aboard. For now, the closest we may get is listening to the passengers on a similar Airbus 330 jet whose flight computer put it into an uncommanded dive over northwestern Australia last October. Qantas Flight 72...the aircraft's flight-control computer went crazy.,,,After seemingly an eternity - in reality, the nosedive lasted 20 very long seconds - the flight crew wrested control of the plane from its wayward computer and made an emergency landing at a remote military and mining airstrip 650 miles short of Perth....The plane has three air data inertial reference units (ADIRUs), ... intended to eliminate the possibility of electronic error...But that's not what happened when one of them went awry on Oct. 7 ...erroneous data spikes on the plane's angle of attack (AOA) - the angle between its wings and the air flowing over them - to the flight-control computer... the same thing happened again, involving a different aircraft, on Dec. 27, Airbus combed its computerized flight files and found data fingerprints suggesting similar ADIRU problems had occurred on a total of four flights....The same VCR-sized ADIRU was to blame in both those cases, although it had supposedly undergone a needed realignment following the 2006 event. All three planes carried the same brand and model of ADIRU, as do 397 of the 900 330s and 340s in the Airbus fleet.... It is not yet known whether Air France 447, an A330, carried the troublesome variety of ADIRU."In these fly-by-wire systems, one never really knows if one has checked out all possible combinations of events to make sure that the computer properly reacts," ...Airbus also told investigators that this particular mathematical formula for flying the plane is found only on its A330 and A340 models. ... other Airbus types, which were reported to be more robust to AOA spikes," the report said. "The manufacturer advised that AOA spikes matching the above scenario would not have caused a pitch-down event on Airbus aircraft other than an A330 or A340."

1 comment:

  1. excellent analysis. I flew with evaair on two flights last year,and experienced severe turbulence,the equipment being an a-330 200. I take your advice and refrain from airbus a-330-200 variety.Both times I flew BKK VIE,and the ride was roller coaster.

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