Crash: Air France A332 over Atlantic on Jun 1st 2009, aircraft impacted ocean

[glencar]

I watched it. It sounds like quite a few A330's & A340's had frozen pitot tube issues. I'm flying to Vienna next month & I hope it's a Boeing of some sort!

[CFD208]

Freezing pitot tubes in those weather conditions wouldn't be specific to an Airbus.  Or you could just be kidding and I just totally missed it.

[alltheway]

I watched it. It sounds like quite a few A330's & A340's had frozen pitot tube issues. I'm flying to Vienna next month & I hope it's a Boeing of some sort!

What is the difference of frozen pitot tubes in freezing conditions and
pitot tubes that freezes up due to heavy turbulence?

in this case frozen (ice) is different than freezes (stopped working due air fluctuations)

[joeyb747]

There was a known issue with pitot tubes on Airbus aircraft. It is not determined if the pitot tube failure caused this crash, but it is known that the airframe involved had not had the upgraded pitot tubes installed at the time of the crash.

"The Acars messages point to a discrepancy between three of the aircraft's speed data inputs of more than 30 knots within a period of less than a second. As a result, the system reported a fault and other subsystems - relying on the speed data - also triggered fault warnings, including the Air Data Inertial Reference Units.

Paul-Louis Arslanian, the head of the French air accident investigation office, BEA, says a pitot tube failure has not been confirmed, merely that the Acars messages point to speed sensors disagreeing with each other. However, he confirms that the aircraft had not yet undergone a pitot tube upgrade the airline had underway.

In a statement defending its actions, Air France says only since May of last year has it seen increased loss of air speed data associated with icing in the pitot probes on A330s and A340s and argues it has been instrumental in driving the upgrade program.

The airline says it upgraded pitot probes on A320 narrowbodies following Airbus's advice in September 2007 to do so; it didn't do so on the Airbus widebodies because at the time water ingestion did not appear to be a problem and no recommendation had been made to do so. Air France insists it asked for a fix once it started seeing anomalies on its A330s and A340s, but that Airbus at first said the A320 issue was different. The carrier says Airbus only let it be known that the A320 improvement could also benefit the A330 and A340. Once it heard that, Air France says it launched the A330, A340 pitot tube upgrade program on April 27 without waiting for a recommendation for Airbus.

The pitot tube upgrade Airbus developed is designed to improve measurement capability of the system."

From:

http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=comm&id=news/AIRUP060809.xml&headline=AF447%20Did%20Not%20Have%20Pitot%20Tube%20Upgrade

See also:

http://www.aviationtoday.com/regions/weur/Airbus-Issues-Pitot-Tube-Warning_72053.html

[CFD208]

What is the difference of frozen pitot tubes in freezing conditions and
pitot tubes that freezes up due to heavy turbulence?

in this case frozen (ice) is different than freezes (stopped working due air fluctuations)

Maybe a pitot that stopped working due to air fluctuations may begin to work again.  Also, what are the odds that all 3 pitots simultaneously stop due to air fluctuations.  Whereas 3 identical pitots would theoretically freeze at the same rate and at the same time in icing conditions such as the super cooled liquid water that FLT447 may have encountered.
The symptoms of a failed pitot would be the same regardless of the reason for the failure. For example ice buildup or air fluctuations.

Just my $.02.  What does everyone else think?

[alltheway]

Also, what are the odds that all 3 pitots simultaneously stop due to air fluctuations.  

Weather was a classic ITZ scenario according to http://www.avherald.com/h?article=41a81ef1/0049&opt=0

http://www.businessdictionary.com/definition/intertropical-convergence-zone-ITZ.html

If it is to form rain, then I don't know if there are supercooled droplets involved, have to ask a weather expert for that....

[delta092b]

Nova on PBS will be showing a program about this accident on FEB 16:

http://www.pbs.org/wgbh/nova/space/crash-flight-447.html

It's currently available on NetFlix.

For any Canadian's wanting to try and get this on Netflix, don't waste your time. I just went through the process of signing up and it's not available outside the US. Sigh.