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AF 447 Search to resume

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AF 447 Search to resume

Old 12th May 2010, 06:23
  #1001 (permalink)  
 
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Hi Chris,
Originally Posted by Chris Scott
So I repeat my question: why do you dismiss this ECAM warning (sorry − advisory) as being spurious, or irrelevant?

As I won't repeat what I already said, I can only clarify one point. I don't believe this advisory is spurious or irrelevant but I just don't know what caused this variation of cabin vertical speed. There is a rule applied to automatism called "garbage in, garbage out". I just don't know if regulation was affected by other faults, crew actions, neither in what direction (up or down), neither at what altitude this event happened, etc.
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Old 12th May 2010, 07:40
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Hello takata,

"Captains static baro" is displayed by ADIRU 1 which is either ON or OFF (no separation is made from the components of Air Data (AD) part of each ADIRU, only Inertial Reference (IR) part may be separated if AD part fails.
Thanks for the explanation and correction. I misread the part associated with the FMGC, and can now see that should the ADIRU input fail, then any schedules in the FMGC become null and void.

mm43
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Old 12th May 2010, 08:37
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cabin v/s advisory

takata;

thank you for your explanations. So, as I understand it now, either the CPC starts sending erratic commands to the outflow valves 4 minutes 16 seconds after the freezing of the pitots, or it is not in control at that point because the negative relief valve is open?

HN39

P.S. The words 'starts' and 'erratic' are, of course, intentionally provocative. Perhaps you should ignore these words.

Last edited by HazelNuts39; 12th May 2010 at 09:28.
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Old 12th May 2010, 09:18
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Hi HN39,
It means that I really hope they'll find the FDR & CVR soon with readable data. Without, there is certainly a lot more possibility (too many?) to explore. I just pointed that it doesn't rule out that she could be at cruise altitude or even higher.
S~
Olivier
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Old 12th May 2010, 09:34
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Hi takata;
thanks for that reply. It certainly 'clears the air' for me.
HN39
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Old 12th May 2010, 12:43
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Back to grizzled's post:

Is it true that the autopsy reports have not been shared with the BEA? If not, why not? You would think the Brazilians would have been very forthcoming with the results? Unless both of them are in some sort of pissing contest.
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Old 12th May 2010, 13:37
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rgbrock1,

"...provided to the BEA."

From the 2nd BEA interim report:

1.13 Medical and Pathological Information

This section is based on examination of the autopsy reports and photographs of the victims made by the Brazilian authorities and provided to the BEA. It should be noted that interpretation of the injuries is disrupted by the effects of prolonged presence in water.

The autopsies performed made it possible to identify fifty persons: forty-five passengers, four flight attendants, including an in-charge flight attendant, and the Captain.

According to the assigned seat placements at check-in (appendix 1), the passengers were distributed around the cabin as follows:

- Eight were seated in business class between doors 1 and 2;
- Three were seated in business class aft of door 2;
- Twelve were seated in economy forward of the over-wing exits;
- Twenty-two were seated at the rear of the airplane, between the overwing exits and the number 3 doors.

Forty-three of the victims had fractures of the spinal column, the thorax and the pelvis. The fractures described were located mainly at the level of the transition vertebrae.

The compression fractures of the spinal column associated with the fractures of the pelvis(2), observed on passengers seated throughout the cabin, are compatible with the effect, on a seated person, of high acceleration whose component in the axis of the spinal column is oriented upwards through the pelvis.

Note: the information from the autopsies does not make it possible to reach a conclusion as to the location of the Captain at the time of the accident.

(2)Fractures of the pelvis can also be associated with the wearing of a seat belt.
GB
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Old 12th May 2010, 13:38
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Hi,

Is it true that the autopsy reports have not been shared with the BEA?
Will be highly surprised if someone can show me than BEA don't received from the Brazilians the forensic reports.
Edited:
"...provided to the BEA."
Crossposting
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Old 12th May 2010, 14:18
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Modified procedure for stall

Thank you for your answer Takata, I also hope now that both recorders will be recovered soon and will provide the real chain of events.
Since this remain a possibility put forward for the AF 447 (unreliable airspeeds, false stall alarms, stall/overspeed), Airbus is currently modifying (with the help of the other major aircraft manufacturers) the procedures to implement in a stall situation:
Le Figaro - France : Les pilotes mal formés au «décrochage» des avions (*)
Jeff

(*) also reported by the AFP & many other French newspapers. Reminder: on June 5 (5 days after the crash of AF447), AF already modified its emergency procedures urging its crews not to apply anymore the "manoeuvre d'urgence" in the "IAS douteuse" procedure at cruise altitude.

Last edited by Hyperveloce; 13th May 2010 at 09:51. Reason: precision about Airbus/AF stall procedures
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Old 12th May 2010, 14:58
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Stall recovery

Hyperveloce;

Not sure why the FIGARO journalist blames the americans. The following quote is from an NTSB report on a stall incident that occurred near Baltimore on 20/10/2002 and was discussed on the old thread:
Icelandair's stall recovery training utilizes procedures contained in the Boeing 757 Flight Crew Training Manual. Procedures for recovering from an approach to stall and from a fully developed stall include the following.
(...)
To recover from a stall, angle of attack must be reduced below the stalling angle. Nose down pitch control must be applied and maintained until the wings are unstalled. Application of up to full nose-down elevator and the use of some nose-down stabilizer should provide sufficient elevator control power to produce a nose-down pitch rate. It may be difficult to know how much stabilizer trim to use, and care must be taken to avoid using too much trim. Pilots should not fly the airplane using stabilizer trim, and should stop trimming nose down when they feel the g force on the airplane lessen or the required elevator force lessen. Under certain conditions, on airplanes with underwing-mounted engines, it may be necessary to reduce thrust in order to prevent the angle of attack from continuing to increase. Once the wing is unstalled, upset recovery actions may be taken and thrust reapplied as necessary.
I would be interested in the Airbus equivalent.

HN39
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Old 12th May 2010, 15:31
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Hi,

Airbus is currently modifying (with the help of the other major aircraft manufacturers) the procedures to implement in a stall situation:
The root of the problem is:
A Airbus (318-319-320-330-340-380) can't stall (provided all the automatic systems are working)
So .. the overconfidence is obvious .. why learn or have procedures for a stall recovery for a plane who can't stall .... ?
Methink the AF447 crash reseted to zero this confidence IMHO
The B-757 procedure is interesting and basic (when compared with Airbus) and assume you are flying the plane in manual (automatisms disconnected)
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Old 12th May 2010, 16:20
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HazelNuts39
The AF procedures & memory item ("vol avec IAS douteuse" & "Manoeuvre d'urgence") are described in the appendix 9 of the 1st interim report:
http://www.bea.aero/docspa/2009/f-cp...90601e1.en.pdf
You will also find a description page 95, appendix 5 (procédures complémentaires "Stall Warning") of the 2nd interim report
http://www.bea.aero/docspa/2009/f-cp...90601e2.en.pdf
thrust is to be set on TOGA and pitch reduced (bank is to be reduced in the same time).
The varied recommandations about how to handle (rely on/discard) the stall alarms are important.
(Note the interesting study page 50 about how several crews reacted to past unreliable airspeeds events)
Jeff
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Old 12th May 2010, 16:57
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Figaro articles about aviation are full of crap. Hardly a reference on this matter in my humble opinion. Beside, readers didn't buy it and reacted strongly.
S~
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Old 12th May 2010, 18:40
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Great bear...

Thanks for that. "My bad" as the kids say nowadays. It was late and I was looking at the first BEA report, wherein they were frustrated because the Brazilians hadn't yet shared the autopsy info.

In any event, having now read the BEA's comments on the autopsy reports, my own comments re the nature and extent of the injuries stand.

grizz
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Old 12th May 2010, 19:15
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Update: "Seabed Worker" - positions

The following graphic depicts the the available positions of the "Seabed Worker" over the past 24 hours. I see no evidence that an ROV is in use, and it appears to me that she is still tending her two AUVs.



The actual position data is as follows:-

11 May 2010 21:35z Hdg 190.5 Spd 00.6 2°40'18"N 31°15'10"W
11 May 2010 19:50z Hdg 224.7 Spd 00.9 2°41'40"N 31°14'45"W
11 May 2010 10:59z Hdg 034.7 Spd 00.6 2°42'13"N 31°10'06"W
11 May 2010 09:15z Hdg 200.8 Spd 00.6 2°41'49"N 31°14'26"W
11 May 2010 07:33z Hdg 265.4 Spd 10.2 2°43'00"N 31°09'12"W
10 May 2010 22:40z Hdg 262.6 Spd 07.0 2°41'07"N 31°10'28"W
10 May 2010 20:54z Hdg 260.9 Spd 00.4 2°42'28"N 31°05'45"W

Methinks, with hindsight, that no debris has been found, and I expect a decision will soon be made on whether to extend the search area around this spot, or to resume the methodical search in the southwest corner of Zone 1. More on this later.

mm43

Last edited by mm43; 13th May 2010 at 18:43. Reason: updated graphic
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Old 12th May 2010, 19:16
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Information, 12 mai 2010

nothing found in the new area, search to resume at the previous location, north west of last known position
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Old 12th May 2010, 19:18
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grizzled

Of the 43 'results of autopsy' mentioned, the conclusions by BEA are supportive of their first statement without benefit of pathologies. The seven remaining bodies are not mentioned as to kind and extent of trauma. Neither do we see determinations relative to those mentioned that perhaps do not support a different thesis. Long bone trauma and potential degloving unrelated to salt water immersion would be instructive, likewise any discussion of the ignored remains. People can break a pelvis by falling off a stairmaster, and break bones in the chest by sneezing. If belted, seated passengers would undoubtedly have incurred trauma relative to the entire body, not just the portion that supports a theory of level and compressive impact. On the other hand, perhaps this information is left out in deference to the families.

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Old 12th May 2010, 21:59
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Cabin pressure

Tekata and others.
I found the following statements in one of my files:
"Report No: 4/2009. Report on the serious incident to Airbus A319-111, registration G-EZAC, near Nantes, France on 15 September 2006
Loss of both airspeed data sources due to loss of the power supplies to ADIRUs 1 and 3.... ADIRU:s 1 and 3 feed data to the cabin pressure controllers. De-energisation of the AC BUS 1 and AC ESS busbars prevents CPC 1 and CPC 2 from operating, because of the loss of power and loss of ADIRU data. Cabin pressurisation would then need to be controlled manually by the crew. The excess cabin altitude warning system would still be operational....
Other significant systems were affected, such as the cabin pressurisation system, where the automatic control function was no longer available. In this incident it did not cause the flight crew any difficulty, however had this failure occurred in other circumstances, the cabin altitude could increase excessively, requiring corrective action. The flight crew would then have to control the cabin pressure manually. Whilst the excessive cabin altitude warning would still operate, it would not be possible to deploy the passenger oxygen masks.
"
Hence, in the cited case it may be possible to have a loss of hull pressure without oxygen mask deployment.
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Old 12th May 2010, 23:19
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Update: "Seabed Worker" - position

Here are the latest positions:-

12 May 2010 11:31z Hdg 279.6 Spd 06.7 2°42'50"N 31°05'16"W
12 May 2010 09:47z Hdg 304.1 Spd 00.9 2°43'01"N 31°06'03"W
12 May 2010 08:04z Hdg 264.9 Spd 00.6 2°42'56"N 31°04'52"W

Hopefully, the next lot will show her heading north!

Edit
: These positions have now been included in Post #1013 above.
-------------------------

Diversification;
Whilst the excessive cabin altitude warning would still operate, it would not be possible to deploy the passenger oxygen masks
Puts a different complexion on the "No Decompression" statement, though I note the type you quoted was an A319.

mm43

Last edited by mm43; 13th May 2010 at 01:54. Reason: added quote.
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Old 12th May 2010, 23:57
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New BEA update May 12, 2010

Back to the region SW of the debris field

Information, 12 mai 2010
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