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AF447 wreckage found

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AF447 wreckage found

Old 18th May 2011, 15:55
  #301 (permalink)  
 
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Alternate law has a low speed and a high speed stability (1.27.30 2/3)both of which can be overridden by a pilot.
At low speed a nose down demand referenced to IAS is introduced and the law changes to direct(stick to surface).High speed stability introduces a nose up demand but pitch protection is lost.
To answer BOACs question the answer is there is no button to force a law change.

Last edited by tubby linton; 18th May 2011 at 15:56. Reason: speeling!
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Old 18th May 2011, 16:03
  #302 (permalink)  
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Hi BOAC

[QUOTE][- this is quite frightening! Are you guys seriously telling us that there is no quick, easy button press to allow back side-stick to raise the elevator and you have to go groping around on the overhead pushing buttons? /QUOTE]

My short time on the A320 would seem to suggest this is the case. You would be trying to 'boot' your bus into the equivilant of windows 'safe mode' whilst in a jet upset with numerous hooters and wailers sounding, visual warnings trying to grab your attention and numerous checklists appearing on the ECAM (the bus equivilent of EICAS) only to be rplaced by further checklists.

Good init!

Hope you are well BOAC


Regards
Exeng
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Old 18th May 2011, 16:05
  #303 (permalink)  
 
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tubby, in an attempt to understand what you posted:
At low speed a nose down demand referenced to IAS is introduced and the law changes to direct(stick to surface).
If you put enough force into your desired input (I want the nose down! or up!) with the side stick, using your hand, you will override computer selected/directed inputs ...
High speed stability introduces a nose up demand but pitch protection is lost.
or will you disconnect it?

As I understand your post, override various law levels is what you can do. Risk is that protections you are used to having will be lost in some law states.

This gives me a mental image of the pilot in a continuing contest with the robot over control surface positions ... until something happens and pilot restores normal law?

Do I read you correctly?
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Old 18th May 2011, 16:06
  #304 (permalink)  
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Good init!
- gulp! I think I need some time to think about that................

(You too, Sir).
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Old 18th May 2011, 16:17
  #305 (permalink)  
 
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Any t_wat can come on this website and speculate, especially before any of the authorities have had a chance to investigate, analyse and report their findings. Wouldn't it be nice if everyone could keep their powder dry until then.
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Old 18th May 2011, 16:27
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A recap of the facts may be appropriate:

What we know,

There were powerful cumulonimbus clusters on the route of AF447. Some
of them could have been the centre of some notable turbulence.

Several airplanes that were flying before and after AF 447, at about the
same altitude, altered their routes in order to avoid cloud masses

Twenty-four automatic maintenance messages were received between
2 h 10 and 2 h 15 via the ACARS system. These messages show an
inconsistency in the measured speeds as well as the associated
consequences.

Twenty-one messages present on the CFR are caused or can be caused by
anemometric problems;

The probes that equipped F-GZCP met requirements that were stricter than
the certification standards

The operator’s and the manufacturer’s procedures mention actions to be
undertaken by the crew when they have doubts as to the accuracy of the
speed indications,

The oxygen masks had not been released; there had been no in-flight
depressurisation,

All of the life jackets that were found were still in their containers,

The airplane’s flaps were retracted at the time of the impact with the water

Three of the eleven cabin crew seats were found; they were not in use at the
time of the impact,

Examination of all of the debris confirmed that the airplane struck the surface
of the water pitch-up, with a slight bank and at a high vertical speed,

I fail to see any relevance to never ending inaccurate irrelevant discussions relating to fbw technology.

Important here is to to find out why AF447 chose not to alter their route.
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Old 18th May 2011, 16:35
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When was the last time an airliner at cruise was brought down by a thunderstorm?

GB
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Old 18th May 2011, 17:27
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Apparently a great opportunity was missed, if wet vee two had been tasked with the search operation it'd been found a long time ago!

The stormy season stopped long ago and is about to start again.
The search windows are always going to be limited in that area, and it takes a good deal of time to get everything planned and set up. If they did not want to find the wreck, it seems illogical to do 4 searches and employ the best in the business while you're at it.

Could not find it. Doesn't radio theory have something to do with signals,when multiplied by something and divided by something equals time/distance?
No idea what you're on about, but I think its safe to say that no it's not that simple.

Press release exonerating Airbus?
Hasn't happened (yet) the only thing Airbus has sent out is that the data from the recorders has been downloaded and is being worked on, and that at this point in time they do not have anything (yet) that needs to be addressed plane wise.

Do corporations have a history of telling the truth?
Sure, when it suits them.

logic suggests otherwise
I think your definition of logic may differ slightly from the norm...
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Old 18th May 2011, 18:22
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Clearly you are in the know so do enlighten us since you are up there with knowledge apart from radio theory clearly.
What is it about radio (radar?) theory that you think is germane in the search case? A lot of the search efforts were conducted using sonar.
I fail to see how a budget airline can postpone ops because they can't afford it, but governments on the other can't just fails me?
What is this referring to? You have me confused. Is this remark related to the search, the crash, or your distrust of governments? (Distrust of government is part of what founded the style of government in my country ... funny little irony there, I think.

My opinion as I am entitled to it aren't I?Good, now go chase parked cars so that others can have their say no matter how ridiculous in your opinion!
OK, you got that off your chest, but I am curious, given the cryptic style of what you wrote (I'd guess English not your first language, and you are giving it your best shot)

Is your concern:
  1. How to search for a crashed airplane in the open ocean
  2. Air France
  3. Flying
  4. French Government
  5. Airbus
  6. Something else?

Last edited by Lonewolf_50; 18th May 2011 at 18:58.
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Old 18th May 2011, 19:12
  #310 (permalink)  
 
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Still confused. Indonesian (and Singaporese and American) governments contributed considerable time and effort to that search. Black boxes were found, and much else. (EDIT: Ah, I see where there was a dispute over who pays for finding the black bos. Got it. Adam air eventually paid ...) (Wikipedia says Indonesian government spent something like 100,000 per day on the search for some time ... not sure how accurate that is).

What is your beef with Air France, AirBus, and French government regarding AF447?

Perhaps the Adam Air tragedy ought not to creep into this thread, it has two serious threads covering it on these forums.

http://www.pprune.org/rumours-news/2...Air+Flight+574

http://www.pprune.org/rumours-news/3...Air+Flight+574
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Old 18th May 2011, 19:18
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Clearly you are in the know so do enlighten us since you are up there with knowledge apart from radio theory clearly.Hint whilst you are watching cows dump.....Something transmits until it disappears, apply basic maths and bingo...a rough estimate.
I'm confused, I thought you were the expert there claiming that it would have been easy to find the plane by "radio" waves? Which basic maths would one apply to find from which location a plane sent something to a satellite? You can't triangulate it because there are no multiple satellites in play here. And even if you could, the accuracy would be not much better than what was already known as the maximum distance the plane could have strayed from LKP. The rough estimate was there all along without black magic.
There was no radio contact otherwise so I'm not sure where the easy part comes in.
It seems to me that you have formed your own conclusions and then shaped "theories" to fit it but without adhering to actual scientific principles.
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Old 18th May 2011, 20:05
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If I recall correctly, when the search was abandoned, it was to take advantage of superior underwater technology that would become available. Commissioning same would not be instantaneous, and given that availability, it apparently seemed prudent to release some of the equipment being used to tasks and users who had been pre-empted for the search.

From the look of it, two things happened: First, additional analysis of sonar records (with more sophisticated signal processing), on land, revealed a very likely place to begin the new search, and secondly, the enhanced subs were able to complete their
mission efficiently.

But I guess that some didn't really read the whole record.
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Old 18th May 2011, 20:39
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To get back to the basics the aircraft flew through a thunderstorm.
The captain was resting and the junior crew could not cope when things went wrong.

Hence the result.

What else needs to be said?
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Old 18th May 2011, 21:05
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cribbagepeg, near the end of phase 3, some of the assets being used had to hurry off because there was an oil well in the Gulf of Mexico spewing great amounts of oil.

For phase 4, the current search, the BEA relied in large part on analysis by a company outside of Washington DC, named Metron. Woods Hole which did the actual search used three remote-controlled submersibles. In the BEA's view, Woods Hole was chosen because they are the best in the world at this sort of deep ocean reconnaissance.

http://www.bea.aero/fr/enquetes/vol....h.analysis.pdf

For phase 3, the principal reliance was on the analyses of the so-called drift group.

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

Neither new sonar analysis or the availability of new submersible technology had anything to do with phase 4.
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Old 18th May 2011, 22:49
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Conspiracy theories? Really? (I've got my tinfoil hat on so I'm OK)

Try to find a green matchstick in a 100m2 area of grass and see how long it takes you.

'nuff said.
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Old 19th May 2011, 07:26
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YouTube - ‪AirTran Flight 426 - crushing hail, shattered windows, no instruments‬‏

This might also explain the loss of airspeed-indications...
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Old 19th May 2011, 07:36
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The conspiracy theorists may wish to ponder on why companies would announce the recovery of the FDR and CVR then lie about the contents, rather than just saying "We couldn't find them".
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Old 19th May 2011, 08:48
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Lonewolf,you are overriding stabilities unlike the protections of normal law.A diagram of failures and how they affect the law you end up in appears in fcom 1.27.30 p1
They do not disconnect.Having looked at the diagram these stabilities are lost with the loss of multiple ADR
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Old 19th May 2011, 09:50
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Originally Posted by Safety Concerns
...The probes that equipped F-GZCP met requirements that were stricter than the certification standards ...
But not the pitot probes that Airbus recommend.
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Old 19th May 2011, 12:09
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News
  • AF447 successfully avoided the storm according to FDR, source close to the investigation tells AFP
  • Final report to be expected by the end of June 2011 according to French Transport State Secretary

Successful storm avoidance by AF447
According to a source close to the investigation, France2.fr reports that the pilots of AF447 have successfully avoided the storm in front of them. (originally reported by AFP and Europ 1)

Original from France2.fr
Parmi les dernières informations recueillies, on a appris mercredi que selon l'examen en cours des boîtes noires, les pilotes avaient évité les zones de turbulences, a déclaré jeudi à l'AFP une source proche du dossier. "L'équipage a réussi à contourner le nuage (de turbulences, ndlr) selon des éléments fournis par les boîtes noires", a déclaré à l'AFP une source proche du dossier sous le couvert de l'anonymat, confirmant une information d'Europe 1.

Source:
Rio-Paris: les causes du crash connues ”fin juin” - Accident - vol AF447 - Actualités internationales - FRANCE 2 : toute les informations internationales en direct - France 2

Roadmap to final accident report: End of June
French Transport State Secretary Thierry Mariani said this morning on France Info that the final results of AF447's accident will be known and published by the end of June.

Comment:
There were two storms in AF447's flight path (a small one at SALPU and a large front at ORARO) and we do not know which one this might have been as there has been a.o. speculation that the smaller storm in the South may have blocked the radar detection of the much larger storm front to the North.

Last edited by DenisG; 19th May 2011 at 13:08.
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