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-   -   Air France A330 accident (https://www.pprune.org/tech-log/376345-air-france-a330-accident.html)

BOAC 11th Jan 2010 21:05

That's it, TP, enquiry over - pilot error:ugh:

mm43 11th Jan 2010 23:33

Seeing this thread has been resurrected, its worth adding that in addition to the BEA's Interim Report No.2, they have also published a Technical Document with the title "Flight Data Recovery Working Group Report" which can be download from:-

http://www.bea.aero/en/enquetes/flig...nal.report.pdf

Backoffice 11th Jan 2010 23:49

TyroPichard said "How do you know this? Have you found the DFDR?"

No, the fact the aircraft entered the ocean in basically a wings level state at a high rate of descent and lowish forward speed is from the BEA interime report. I assume, perhaps incorrectly the aircraft was probably in a stalled state at that time.

What I'm really trying to understand and this is perhaps backed up by the lack of life-jackets on passengers - so I presume no message back to cabin to prepare for crash landind in sea, is whether the crew had accurate or any altitude information.

i.e. Perhaps it wasn't just the pitots that iced up, but so did the statics but there just happened to be no acars which pointed to it.

mm43 12th Jan 2010 00:07

@Backoffice

Perhaps it wasn't just the pitots that iced up, but so did the statics but there just happened to be no acars which pointed to it
Well, yes there was, but everyone has suspected the pitots were the problem. Whether the static ports were also involved, we will never know. Ice reverts to water and all traces that could lead to your static port theory have gone forever - subject to the CVR revealing that the pilots had no meaningful info from the standby altimeter.

Backoffice 12th Jan 2010 16:49

@mm43

Agree with all you're saying.

Question though, as the static port/vent is part of the ASI circuit and is necessary for both VSI and ALT why have we assumed from day one that the pitots are the culprit ?

TyroPicard 12th Jan 2010 16:58

Backoffice

What I'm really trying to understand

is whether the crew had accurate or any altitude information.
The point I am really trying to make is that nobody knows what happened between cruise altitude and the ocean. Until we do all is conjecture.

mm43 12th Jan 2010 19:05

@Backoffice

.. why have we assumed from day one that the pitots are the culprit ?
Something to do with the pitot bore size and facing the direction of travel, as opposed to the static ports, very large bore in comparison and open to the side.

Nothing is impossible, and maybe the Thales pitot probes are not the problem after-all. They just happened to be fitted to a/c that happened to be in the wrong place at the wrong time.;)

Backoffice 12th Jan 2010 19:53

@TyroPicard & mm43

Yep, we'll never know until those boxes are recovered.

For those analyzing the acars messages just ask yourself what if it's not the pitots feed but the static feed that has gone u/s, how would that effect your analysis of the acars messages ?

Backoffice 12th Jan 2010 23:31

This one won’t go away in my head so have to post this theory here to be shot down.

Aircraft encounters cb cells, becomes covered in super cooled water droplets, temperature changes or encounter with ice crystals turn this to ice over much of the fuselage…ice blocks static vents, pitots may be unaffected.
Crew aware of an airspeed problem but altitude and vertical speed appear stable.
No mayday sent, no cabin announcement.:sad:

mm43 13th Jan 2010 07:20

@Backoffice

I think it would be worthwhile to go to http://www.pprune.org/tech-log/376433-af447-222.html and read pages 222 through 225. A lot of what you are inferring has been raised before.:ok:

Backoffice 14th Jan 2010 00:41

@mm43
Re-read and yes agree it has been touched on - like your graphics by the way.

Without going into many of the complex issues raised on those pages and of course the question we will have to await while the naval experts try to find the proverbial needle is, did the crew have any idea where they were in space (altitude) - I for one don't think they did.

CorkStudentPilot 17th Jan 2010 02:15

I agree with everyone that posted about the Pitot!!

I think this crash is going to be something along the lines of Aeroperu 603
and Birgenair 301. The biggest culprit is darkness!

let say the pitot was blocked the aircraft on board computer would have picked up on the problem, when it noticed the difference in airspeed and altitude between the two sets of instruments!! that then triggered the ACARS message!!

both pilots would have gotten confused by the different readdings and flown the aircraft into the ocean!!!

Just my opinion (Sorry if thats what like everyone said, i didnt read the other posts)

usanxb 13th Jun 2011 02:37

Air France A330 accident
 
I know of the seriousness of this accident and the loss of life on the part of all passengers and Air France crew so this a very sad thread. My heart goes out for all of those involved. However when flying as a passenger I shall never stop flying with AF.

My comments are more related to the automated computer systems involved in modern airbus aircraft. For example one theory is that when the ASI's shut down, then also so did the onboard computer. Since us pilots know it's even possible to fly without ASI using the standard operating procedures to avoid an alleged high altitude stall I would like to pose the following question to fellow pilots:

Would we prefer the onboard computer to reset the flight controls into the mode of standard operating procedures giving us time to take over?

Or would we prefer the onboard computer to simply shut down and give us a 100 error messages while we try to figure things out?

john_tullamarine 13th Jun 2011 08:16

We probably don't need two similar threads on this topic. I'll lock this one but include a link at the start of the other so that this doesn't disappear into the swamp.


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