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AF447 wreckage found

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Old 22nd May 2011, 21:43
  #381 (permalink)  
 
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MFgeo Thanks, your links would seem to justfy my rant.
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Old 22nd May 2011, 22:38
  #382 (permalink)  
 
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Which of your rants would that be? The one about flying at coffin corner, which it didn't and they don't?. Or the one about how the aircraft prevents pilots from hand flying, which it doesn't?

Or how you now seek support in articles which are about none of what you ranted about?

I hope you are merely trolling as that would, to some degree, make you appear less of a you know what.
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Old 22nd May 2011, 23:30
  #383 (permalink)  
 
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Which of your rants would that be? The one about flying at coffin corner, which it didn't and they don't?. Or the one about how the aircraft prevents pilots from hand flying, which it doesn't? Or how you now seek support in articles which are about none of what you ranted about?
Did YOU bother to read any of those articles?

The Myth of the Perfect Automatic Man « Dark Matter
Criticizes Airbus design philosophy calling it "unnatural".

AF 447 – What The Crew Did … Maybe « Dark Matter
States that the airplane was in coffin corner.

I'm not defending either the facts or the viewpoints in those articles. But they say what they say. And a fair reading of what they do say does indeed support vee-tail-1 "ranting" or "trolling".
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Old 22nd May 2011, 23:48
  #384 (permalink)  
 
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Did YOU bother to read any of those articles?
No.

When a "article" such that has been forwarded appears that does not contain a nationalistic/jingoistic slant, then fine, until then.......

.....REALLY it's becoming TIRESOME....
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Old 23rd May 2011, 00:06
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A casual comment in a single article about it being at coffin corner without offering any proof or anything resembling proof, amounts to nothing. It supports just as much.

I suggest a search for Hazelnuts and PJ's posts on the subject.

The other article linked to offers neither support or opposition. It is merely a subjective description without judgement.

The series of articles is a compilation of guesswork and assumptions mixed with a little fact.

So yes, I did read them all. .
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Old 23rd May 2011, 02:14
  #386 (permalink)  
 
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Cool

Well.......
Just go to the webpage of BEA and you will see that they DO ALWAYS publish
the CVR transcript.
Indeed .. in their final report
For this Friday communication (that was the question) .... forget it
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Old 23rd May 2011, 09:01
  #387 (permalink)  
 
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I did read one of the links to whom some posters refer, and it clearly states:

For the moment we don’t have hard data such as a Flight Data Recorder (FDR) would provide, but we do know something of the psychology of human behaviour and perhaps that can shed some light on the possible actions of the crew.
Or alternatively, perhaps some can speculate wildly to increase the number of hits on his blog.

Give me strength.

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Old 23rd May 2011, 09:02
  #388 (permalink)  
 
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vee-tail-1

As an Boeing and Airbus driver I feel that your 'RANTS' are just that -RANTS. Fear comes from lack of understanding, or ignorance - I suggest that you go and learn a little more about what you are RANTING.
Just because an operator plans a flight too high for the conditions doesn't mean that you have to fly there - it would be negligent to do so and that is why there are huimans on a flight deck. In fact this frequently happens because most flight deck try to carry more fuel than accountants like resulting in heavier aeroplanes and lower 'coffin corner' - perhaps you would like to RANT about safety in fuel policy too.
Most Airbus operators encourage as much hand flying as Boeing operators and most pilots only fly because they love flying - not just monitor.
Monitoring the approach of coffin corner is exactly the same on an Airbus as a Boeing - responsibility for ensuring it's avoidance is the same flight deck responsibility ( and often predicted by the same manufacturer of FMS ) and skill. And...I'd certainly prefer to be in an Airbus if I had to cope with consequences - degraded law on not.
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Old 23rd May 2011, 09:06
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From the two articles quoted earlier:

The BEA has said it will release details of the circumstances of the crash on May 27, but that the cause of the crash will take longer to elucidate
.

-and

The BEA this week condemned conflicting media reports on the supposed cause of the crash.

The BEA's official explanation of the available data is expected to come in an interim report which it plans to publish in the summer. The agency says the black box data is intact and should allow investigators to shed light on the disaster.
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Old 23rd May 2011, 12:02
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News is that the Captain rushed to the cockpit and shout instructions for the pilots and then the aircraft became uncontrollable, we know the rest of it.
When they are going to release the CVR contents?
We all need to know what really happened.
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Old 23rd May 2011, 12:14
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Der Spiegel

Hi there,
The German newspaper Der Spiegel releases 2 news derived from the data recorders:
- the CVR would show that M. Dubois, the captain (the most experimented), was not in the cockpit when the serie of problems began, and rushed to the cockpit to try to shout his orders to the flying crew
- the AF 447 stalled at high altitude due to a sudden pitch up, but whether it is a crew manoeuver or a response of the autopilot (just before it disengaged, fueled with erroneous airspeeds) is not avalaible.
This pitch up seems similar to the Bigernair case. I don't get why the AP would react to an underestimated airspeed by increasing the pitch angle ? Wouldn't it be an AP reaction to an overestimated airspeed ?
Jeff
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Old 23rd May 2011, 14:08
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Air France 447 May Have Stalled on Sensor Failure - Bloomberg


Air France 447 May Have Stalled on Sensor Failure

Air France Flight 447’s flight recordings show the aircraft lost speed and stalled after its airspeed sensors failed while the two co-pilots were at the controls, two people with knowledge of the investigation said.

The chief pilot, Captain Marc Dubois, was not in the cockpit when the Airbus A330’s airspeed sensors malfunctioned, causing the autopilot to disengage over the Atlantic Ocean, said the people, who declined to be identified because the investigation is still confidential.

A low-speed stall occurs when an aircraft slows to the point where its wings suddenly lose lift, an incident pilots learn to overcome in basic training. Flight 447’s last automated transmissions logged faulty readings from airspeed sensors that caused the autopilot to shut down in bad weather, minutes before the accident in which all 228 passengers and crew perished.

“To get out of a stall, you stick the nose down and wait for gravity to speed up the aircraft,” said David Learmount, a former U.K. Royal Air Force pilot and safety editor at Flight International. Pulling out can be straightforward, “providing you realize you’re in one,” he said.
Making Progress

Air France spokesman Jean-Charles Trehan said the company had no comment on the investigation’s early findings. France’s BEA air-accident investigation bureau also declined to comment on the circumstances of the June 1, 2009, crash.

Investigators say they are making progress after maritime search and salvage experts retrieved the flight data and cockpit voice recorders this month from a depth of 3,900 meters (12,800 feet). Dubois was among the victims recovered from the sea surface in the weeks after the crash.

The failure of the Thales SA (HO) airspeeds sensors, or Pitot tubes, occurred while the plane was cruising at about 35,000 feet, four hours after take-off from Rio de Janeiro. At that stage in the Paris-bound flight, it is routine practice for the captain to take a rest break and leave the co-pilots at the controls, Air France has said.

Airbus declined to comment beyond a BEA-approved May 16 telex, in which the company told airlines that preliminary black-box analysis yielded no additional recommendations. Two months after the crash, Airbus advised A330 and A340 operators to replace the Thales sensors with a model from Goodrich Corp. (GR)

A stall is typically preceded by shaking and vibrating of the aircraft, and modern jets are equipped with a steering-stick shaker and audio warning to alert the pilot. Stall recovery requires pilots to coordinate the aircraft’s angle and power to the engines to avoid aggravating the situation.

According to a report by Der Spiegel Online, which could not be verified, the black boxes reveal that the Air France plane climbed sharply after the speed-sensor failure and Captain Dubois returned to the cockpit before the crash.

The BEA has said it plans to issue a preliminary factual statement May 27 on the findings of its initial black-box analysis, without identifying any of the accident’s causes. An interim report is due in mid-July.

To contact the reporters on this story: Laurence Frost in Paris at [email protected]; Andrea Rothman in Paris at [email protected]

To contact the editors responsible for this story: Chad Thomas at [email protected]; Benedikt Kammel at [email protected]
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Old 23rd May 2011, 14:24
  #393 (permalink)  
 
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Anton Du Flasheart:
Monitoring the approach of coffin corner is exactly the same on an Airbus as a Boeing - responsibility for ensuring it's avoidance is the same flight deck responsibility ( and often predicted by the same manufacturer of FMS ) and skill. And...I'd certainly prefer to be in an Airbus if I had to cope with consequences - degraded law on not
When I watch the daily Lufthansa A340 lift off from DFW and stagger into the air for its journey to FRA as it looks to be passing maybe 2,000 AGL 15 miles north of DFW, I note that 777's/767's/757's are all accelerating at 10,000 feet or so in the same spot when loaded for their max range flights. Yes, would be grand (not) to have all that excess A340 thrust. At least tho, like a B727, the A340 is very fast hundreds of miles later at cruise alt.
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Old 23rd May 2011, 15:15
  #394 (permalink)  
 
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Air France plane climbed sharply after the speed-sensor failure
So did Pulkovo 612 - climbing sharply before it plunged to the ground, at least that's what the recorded parameters said. I wonder if it was an updraft or some kind of barometric failure...
http://sokolov.org.ru/RA-85185.jpg

Last edited by vovachan; 23rd May 2011 at 17:02.
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Old 23rd May 2011, 15:15
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Oh Dear SKS777, I don't think you are a pilot. All the 777, 757 and 767s you are watching are actually overpowered in order to meet take off safety requirements. An aircraft must be able to continue its take off safely in the event of an engine failure after its go/no go speed (V1). So, if a twin loses a donk, it is on half power, with four engines it has only lost a quarter. It is no wonder, therefore, that the twins seem to leap off the ground like spring chickens! In the cruise, however, all that excess power is an embarrasment as the match between engines and airframe cannot be as precisely matched as with four engines. Have you ever seen a 747 or 707 (KC135) stagger off? No different to a 340 I assure you!
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Old 23rd May 2011, 15:39
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In the cruise, however, all that excess power is an embarrasment as the match between engines and airframe cannot be as precisely matched as with four engines.
can you pontificate then why the 340s, 380s and guzzle more fuel during cruise (payload vs. fuelburn) than 330s or 777s?? Silly statement.

As to the news releases:
It may well be that the pitots iced up, the flight computers sensed high speed and the autoflight system wanted to counteract and pitch up and reduce thrust, as it could not cope it disconnected the autopilot and "told" the pilots you have controls.

What I am curious now, is what was the input of the pilots and did the aircraft obey them, or did the duped protections still inhibit a eventual stick down input!

That will be the really interesting point.
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Old 23rd May 2011, 16:21
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What I am curious now, is what was the input of the pilots and did the aircraft obey them, or did the duped protections still inhibit a eventual stick down input!
Hmmm, I had a similar thought.

Although the protection is only active in Normal Law and can be overridden in Alternate Law (at least that's the case for 320 family)

Whilst I can't be bothered to trawl though the pages of nonsense on this forum I believe I read that the ACARS messages indicated that the aircraft did downgrade to Alternate Law?
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Old 23rd May 2011, 16:32
  #398 (permalink)  
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With the autoflight inop. and Protections not performing as advertised, the question is actually, "Did they manage to get the beast into Direct?"
 
Old 23rd May 2011, 17:12
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What I am curious now, is what was the input of the pilots and did the aircraft obey them, or did the duped protections still inhibit a eventual stick down input!
Flying at night, at cruise altitiude, over the ocean, no visual refs... In the middle of some nasty weather... Airspeed indicating overspeed. Who would pitch down an aircraft under these circumstances?

By the way... GPSes does not get clogged by ice. How much tail/head-wind would be required to stall/overspeed an aircraft if GPS speed was used as input to AP/AT? Of course, it would not be the one and only speed reference. Say, we use GPS speed as a "sanity check" to catch a clogging pitot? Is it even possible? Probably not...
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Old 23rd May 2011, 17:52
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What a horrible Catch-22.

The diagnosis appears to be, from the leak (I realize that isn't the whole picture) airspeed unreliable, pilots thus unaware of actual aircraft performance, and they must make a nose/pitch decision to control aircraft when X event happens. (Nose pitch up? Stall warning based on AoA? High speed warning from otto due to approaching? No, scratch that one, airspeed not reliable ... )

If you don't know your actual airspeed, you may change pitch in the wrong direction (see what the guy in Buffalo did a while back, wrong input to a stall scenario) as you either approach Mach limits, or you approach high speed stall. If you guess wrong in the corrective input, you make the situation worse. Hell of a coin to flip there, and not a lot of time to ponder.

Granted, maybe "pitch and power we had set a moment ago" is the proper response with a flurry of error reports and warning audio going off? But to get to that decision you have to figure out the first issue, that your airspeed (a triple redundant sytem and a primary performance indicator) has gone awry. How long does that take, what are the cues? Aside: Over at tech log sub forum, poster takata has some interesting info on airspeed sensing failures from Airbus, a few years old.

Is task/sensory overload an issue? Someone at Tech Log mentioned the plethora of warnings and ECAMS messages for the Qantas A380 turbine disk loss ... were the gents in AF 447 similarly assaulted by a lot of warnings at once?

To top it off, you have no AoA indicator in the cockpit (do I have that right, in the A330, no AoA gage to read?). AoA gage might help you direct the attitude to set acceptable performance, while you sort out what is wrong with your airspeed sensing system.

AoA is the basis for some of the protections built into the various laws for Airbus flight control system, but pilots don't have an AoA gage.

Would having an AoA gage have been helpful to this crew, I wonder?

Last edited by Lonewolf_50; 23rd May 2011 at 18:18.
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