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AF 447 Thread No. 7

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AF 447 Thread No. 7

Old 25th Mar 2012, 23:20
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Originally Posted by HN39
Hmmm, key assumption?? The "on the threshold of stall warning" trajectory with specific excess thrust (T-D)/W = 0.15 results in level off after 15 s (was 18s) at FL76, Mach 0.51, 295 kCAS, az=2,24 g. An A330 is not a fighter.
No, it most certainly is not a fighter. But we have gained ~2000 feet in pull out altitude from the initial cut at at the pull out. We haven't even hit the cornering speed. To avoid secondary stalls, we are likely to have to give some of that hard earned altitude back.

If fighter maneuvering theory helps, we should understand the theory. Far better to pull out at +100 feet than -100 feet. When your life is on the line, you may have to walk a delicate line between not making a fatal maneuvering error (secondary stall) and achieving maximum performance. All this while your heart is beating 10 miles per minute. Give yourself as much leeway as possible. In Alternate law, you govern the AOA. Don't mess it up!

Originally Posted by OK465
It will "BFM" better with the slats out.
Yep, but it will roll on you if you tear one off. Best bet is to leave them in. The fewer things you have to do during the critical pullout, and the fewer risks you have to take, the better.




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Old 25th Mar 2012, 23:25
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Hi

Interim #3, page 94

02:12:04 - 02:12:07 The airbrakes are controlled and deployed

02:12:07 PNF (left seat) said "No above all, don't extend"
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Old 26th Mar 2012, 00:20
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@NeoFit:


Hi
Interim #3, page 94
02:12:04 - 02:12:07 The airbrakes are controlled and deployed
02:12:07 PNF (left seat) said "No above all, don't extend"
Don't extend........The airbrakes (A.K.A. Flight spoiler or Speedbrake)
This is clearly visible in the FDR spoilertraces @ 02:12:04 - 02:12:07.

Another hint/clue.........
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Old 26th Mar 2012, 01:48
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A33Zab

Better than that. In BEA IR #3, there is a picture of a recovered Flap rail that was EXTENDED. The "Extended" was in their caption, it is not my conjecture.

Hypothetically, since S/F trace is U/A, it cannot be ruled out that that is exactly how the Rudder was reinvigorated after RTLU instant at a/p loss.

A hint? RIGHT ROLL, the bias is apparent from the outset, and cannot be explained. He had extended the brakes, and stowed them, and the evidence is unclear that all were successfully stowed at deselect.

For that matter, it is not impossible that one or more spoilers was lost in the air.

Find the pic, and see what you think. F1 is possible, eithwr as a STALL recovery memory item, or as a desperate attempt to gain control, or lose a/s or Level out, or......

Lyman
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Old 26th Mar 2012, 02:30
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Final BEA Report?

Anybody know when the final report from BEA will be issued?
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Old 26th Mar 2012, 02:32
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Witness Marks

Find the pic, and see what you think. F1 is possible, eithwr as a STALL recovery memory item, or as a desperate attempt to gain control, or lose a/s or Level out, or......
Lyman, on a scan through BEA interim report 3, I found no such picture-but I admit to being occasionally unobservant. There was a picture of a flap track in an earlier report, but that showed the trailing edge flaps to be retracted.

There was a tabulation of the final readings and configuration including this bit:
Last values recorded on the FDR....
Configuration Clean
When aircraft get crumpled, the forces are very high, and adjacent parts bang together. This generally leaves copious marks of where components were located at the moment of impact. BEA would have known from the recovered wreckage almost immediately if a flap or slat was extended. It would have been published in IR3.
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Old 26th Mar 2012, 02:39
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Anybody know when the final report from BEA will be issued?
Nothing new on the BEA site. Publication of the report is planned for the first half of 2012.
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Old 26th Mar 2012, 02:45
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Mach, hi. I looked again, dismayed, at IR #3 , and struck out also. It was group of three flap tracks, two retracted, and the third extended. Color pix, where?

BEA would not caption extended without an extension actual, so I think not wreck scramble. It is around. I swear it was #3. I'll find it.
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Old 26th Mar 2012, 02:59
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Nothing new on the BEA site. Publication of the report is planned for the first half of 2012.
I had read July, as per BEA, but can't remember exactly where I saw that. Let's see, April, May, June...............zzzzzzzzzzzzzzzzzzzzzz
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Old 26th Mar 2012, 03:51
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Cool

Hi,

Better than that. In BEA IR #3, there is a picture of a recovered Flap rail that was EXTENDED. The "Extended" was in their caption, it is not my conjecture.
Confused ?
In the BEA report N°2 (english) it's indeed a photo ... page 21



and this caption:
From these observations it can be seen that the general direction of the loads
that caused these deformations is bottom-upwards.
Several parts of the flap extension mechanism fairing were found. There were
marks on two of them (positioned at the level of flap track No. 3), made by the
flap extension track on impact. Analysis of these marks (morphological and
dimensional examinations) and comparison with an identical aircraft made
it possible to determine that the flaps were in the “retracted” position at the
time of impact with the water (measurement of the distance between the
track and the lower surface of the flap, position of the carriage on the track).
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Old 26th Mar 2012, 09:35
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Originally Posted by Lyman
(...)I cannot state honestly what possessed the designers of Bus products to hide the SS one from the other.
Are you sure they are "hidden"?
AFAIK, the position of the other sidestick is less obvious than the position of the yoke (particularly with conjugued yokes), but not impossible to assess, as you seem to think it is.
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Old 26th Mar 2012, 10:53
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Better than that. In BEA IR #3, there is a picture of a recovered Flap rail that
was EXTENDED. The "Extended" was in their caption, it is not my conjecture.
Thx, jcjeant for explaining this misleading picture.

Hypothetically, since S/F trace is U/A, it cannot be ruled out that that is
exactly how the Rudder was reinvigorated after RTLU instant at a/p loss.
Well, NO....IF S/F where selected (in flight S/F lever #1, slats only! are extended to 16°) the RTLU traces would have shown +/- 31° to allow max. rudder deflection of 35° within 10s.
There is no sign of such RTLU movement so we can conclude FLAPS were FULL retracted and slats (only IF selected) never reached the 16° position.

A hint? RIGHT ROLL, the bias is apparent from the outset, and cannot be
explained. He had extended the brakes, and stowed them, and the evidence is
unclear that all were successfully stowed at deselect.

For that matter,
it is not impossible that one or more spoilers was lost in the air.
No abnormalities at the spoiler traces before 02:13:40 (@ PRIM1/SEC1 selected OFF).
I admit these are servo positions only, but why should a panel separate if the lower gap is closed by the retracted! flaps.

Last edited by A33Zab; 26th Mar 2012 at 11:41.
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Old 26th Mar 2012, 13:14
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Caption in report

Jcjeant, technically Lyman is correct, albeit not with respect to the ultimate question.

Your quoted language is from the text.

The actual caption to the picture in the English version of the report at your citation reads:

"Flap extension mechanism (or flap track) no. 3 in extended position."
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Old 26th Mar 2012, 13:41
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Interim report no. 2 makes it quite clear that the two images of flap track no. 3, in both retracted and extended positions, are not of recovered wreckage but from an identical aircraft used to analyse marks left on recovered flap track fairing parts.

Another misrepresentation of items taken out of context.
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Old 26th Mar 2012, 15:40
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Originally Posted by jcjeant
Confused ?
No, just spectacularly amused. How come we can have sensible and rather short discussion when African pilots flying Boeing get disoriented splash it in the Mediterranean while AF447 disaster brings out myriad of hypotheses that would be charitable to call unrealistic?
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Old 26th Mar 2012, 16:26
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Well, in defense of all the speculators.....this crash seems to be much more complicated and mysterious than that straightforward cockup. And, of course, the 'extra' FBW dimensions of this airplane and situation add many layers to speculate about!

Besides (I would argue as devil's advocate), It's a very long wait for a resolution, over three years, and I think ppl are tempted to furnish their own "resolutions." Inquiring minds want to know, or else just make s*** up!

This crash raises all sorts of questions and fears about the long-simmering Airbus control issues/debate, and gives the multitudes all kinds of fodder to discuss that. Stop me if I am making sense.

But yeah...."flaps"??? C'mon, get real!
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Old 26th Mar 2012, 16:40
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Organfreak

A strong hint is furnished on the CVR, when PNF admonishes PF not to extend flaps. Later, there is an order to "Climb". One second later, we hear "NO, don't climb". "well, then, go down."

You question FLAPS? I wouldn't, but the man flying wanted to extend them, NO?

This is not speculation, this is an extension of CVR evidence. This kind of confusion develops on the Flight deck of a Legacy wide body in ETOPS?

This is not a third World cock up. This is a First World C/F. Boeing got nuthin to do with anything. This is NOT AB v. B. That is a sideshow.

cheers, bill
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Old 26th Mar 2012, 16:55
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@ Lyman:
A strong hint is furnished on the CVR, when PNF admonishes PF not to extend flaps. Later, there is an order to "Climb". One second later, we hear "NO, don't climb". "well, then, go down."

You question FLAPS? I wouldn't, but the man flying wanted to extend them, NO?
Well OK, YES, but at impact? Evidence does not support. As to the cause of the crash, I highly doubt that flaps had much to do with the end result. Am I being difficult? Sure, that's my hobby!

This is not a third World cock up. This is a First World C/F. Boeing got nuthin to do with anything.
That's what I said, so I'm glad we agree on that much! But,

This is NOT AB v. B. That is a sideshow.
I don't agree. Numerous speculative (I admit) posts have convinced me that the design of this airplane may have contributed to the confusion, but, of course, not directly responsible for the accident. I think the arguments in favor of very obvious pulled-back yokes are very convincing. Hell, I don't fly, and even I would have intervened had I seen that! YMMV.
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Old 26th Mar 2012, 17:07
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AB/B

When a pilot types, he is assumed to know the a/c. Is AB different? Yep. In approved and certificated ways? Yep, no room to argue. One knows his machine, or he does not. If anyone is confused due prior Boeing time, or vice versa, get a different job. It is ironic that the focus of some criticism is the system that has made the BUS so safe. Who would think to make ALTERNATE LAW a focus, especially re: high altitude upset? As I said before, my neighbor flew the 320 for years, for a Legacy carrier. In his thousands of hours he was out of NORMAL LAW not once. Fair?

The reason there is yet such passion re: 447 is because of the sheer number of shortcomings, poor decisions, bad design, etc. that killed these folks. We get complacent, and complacency leads to more complacency, then we forget.......

add. The lady in the RHS in COLGAN didn't push the yoke forward, and she had more time than her Captain. Don't be so sure "I would have intervened..."

then it happens...... I for one believe the attention is justified, and we let this go at great peril to all of us who fly....
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Old 26th Mar 2012, 17:12
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You question FLAPS? I wouldn't, but the man flying wanted to extend them, NO?
Lyman, I hate to say this, but you are flaunting your confusion and lack of knowledge.
You are confusing speedbrakes and flaps. One goes up, one goes down on the A330.
Time for you to re-read FCOM flight controls again.

PM was telling PF not to extend the speed brakes and PF complied after briefly extending the speedbrakes. If all the emotional sparks had not been flying at that point, one of them might have realized, "Hey! We put out the boards and nothing happened. Maybe we are very slow."
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