Air France A330 - Missing over Atantic

[SCCutler]

228 Souls on Board, flying from Rio to Paris. Last reported "electrical problems."

Pray for them.


http://www.cnn.com/2009/WORLD/americas/06/01/air.france.brazil/index.html

 

[Jim Logajan]

Metal wire? Suhriously? I've never heard of such a thing.

I've heard of it, but it is pretty old technology; here's a quick primer on Wikipedia: http://en.wikipedia.org/wiki/Wire_recording

 

[Jim Logajan]

Wow - just watched the PBS NOVA episode that aired back in February and mentioned earlier in this thread (can be watched online here: http://www.pbs.org/wgbh/nova/space/crash-flight-447.html) and if these current reports are true, the hypothetical sequence of events proposed by NOVA may have been close to the truth - such as it will ever be determined.

 

[Jim Logajan]

I woudn't believe anything NOVA puts out. They just got the FDR data this month, and it's WAY too early to start building up a dramatization of the "last moments".

Way too early!? That assertion with respect to the NOVA episode is "not even wrong." The show they did was nearly two years after the accident and no one by that time expected the FDR or CVR to ever be recovered. Are you saying there should be, say, no less than 5 years before anyone can say "well I guess we now have all the facts and it is OK now to start analyzing the data we do have?"

How long (without insisting on prescience) do you think NOVA should have waited before producing the show?

I'm also curious what "dramatization" you objected to in the show it appears you haven't seen? Which specific aspects do you object to, and why?

(Big hint: as these things go, and given what they had to work with, I thought the show was well done. Great introduction to accident analysis for its target audience, the lay public.)

 

[Jim Logajan]

I'm not clear on why the AoA was available for recording but not presented to the pilots at the time, nor why it would not have been affected by icing. Was it determined from an AoA vane? Pressure differential between two tubes? Some other mechanism?

(I suppose in theory one very low-tech "never again" backup would be to put an AoA vane directly in front of the cockpit window where jet pilots can always see it. Kind of like the yaw string glider pilots can use because there is no prop on the nose messing with the airstream.)

 

[Jim Logajan]

Part of it is the airlines give people jobs ensuring others live to see another day and pay 'em $25K a year.

I don't believe Air France pilots get paid in dollars. Also, some non-authoritative sites on the Internet suggest Air France pilots are among the best paid, anywhere.

 

[Jim Logajan]

It's here: http://www.avweb.com/news/avmail/AVmail_LettersToTheEditor_204773-1.html

It's also very interesting. I made a comment on the Jetwhine blog about this subject and I think this letter agrees.

I'm not bagging on FBW in general, just the Airbus design philosophy. It's a bad UI, period.

My understanding is that:

1. This is not the first time the pitots failed on an Airbus and the pilot had to deal with it. This is just the first time it lead to a fatal plunge.
2. That there is a book procedure to set the throttle and elevator trim to specific settings that, had it been followed, could have got them safely out of the situation.

Are either of the above incorrect enough to indicate that the fault lies more with poor ergonomics than a pilot not resorting to their training?

 

[Jim Logajan]

Just released from BEA:

Interim report:
http://www.bea.aero/fr/enquetes/vol.af.447/note29juillet2011.en.pdf

Safety recommendations:
http://www.bea.aero/fr/enquetes/vol.af.447/reco29juillet2011.en.pdf

 

[Jim Logajan]

So the facts are:

1. Three experienced pilots on board.
2. Airspeed indications become unreliable due to pitot icing.
3. As a result of the erroneous airspeed and confusing automated warning systems, the pilots induce a stall at high altitude.
4. Throughout the stall and descent the flight crew did not recognize the condition of the aircraft and did not take correct measures necessary to return the aircraft to level flight.
5. As a result all aboard the Northwest Airlines Flight 6231 Boeing 737 are killed.

Thirty-five years later only point 5 needs editing. (I copied point 4 verbatim from the NTSB report, linked below.)

http://www.airdisaster.com/reports/ntsb/AAR75-13.pdf

 

[Jim Logajan]

Tend to agree, but it might have been contributory that the force required to maintain full nose-up on the stick was de minimis - one wonders whether the PF even realized he was doing it.

The translated cockpit transcript seems to indicate that during the descent the captain and PNF realized the PF was pulling back and told him to stop; but near the end the captain and PNF also resorted to pulling up:

The BEA said neither pilot followed the manual aircraft handling procedure for high altitudes, for which they had received no training. The crew did not alert each other to the differences in pitch attitude and vertical speed.
[...]

Around fifteen seconds later, the PF pulled the nose down. The angle of attack decreased, the speeds became valid again and the stall warning sounded again. Confusion reigned in the cockpit.
The PNF says: "You're going up. Go down, go down, go down."
"Am I going down now," the PF said.
"No, you're going up," the captain said.
[...]
02:14:18 -- The captain urged the PNF to pull up. "We're pulling up, we're pulling up, we're pulling up," the PNF said seconds before the recordings stopped.
http://news.yahoo.com/factbox-final-moments-flight-af447-crash-150127685.html