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AF447

Old 17th Jul 2009, 21:38
  #3741 (permalink)  
 
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Hi,

Quick or not, regarding QF72, there was nothing to be done as long as the protections were in control ...
So true ... so sad ...

Bye.
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Old 17th Jul 2009, 21:44
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The transducer is a 2 axis inclinometer (G1 & G3), and the large piece may well be part an Arian nose fairing.

See blue section " Herschel Plank" with lump at top plus gray stripe above.

http://rascmontreal.org/IYA-2009-InM...go_fairing.jpg



Now look at the dark section on the wreckage near the man's head, plus a similar gray ring.

http://www.kaieteurnewsonline.com/im...ne-2-copy1.jpg
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Old 17th Jul 2009, 21:52
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Could anyone please explain the signifigance of finding this IMU.
How it can help in the investigation?????
Absolutely none, most likely.
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Old 17th Jul 2009, 21:52
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IMU's

RE: Will Fraser (#3739)

Will,
my reasoning was simply: the airplane has three ADIRU's, each containing an ADR and an IRU, what would it need an IMU for? (by the way, my understanding is that the IRU, as any INS, comprises laser-gyros and accelerometers for all three axes, it cannot derive speeds and position from gyros alone).

In addition, units like this in an airplane would have to be line-replaceable, easily accessible for maintenance, the pictures didn't looke like that.

regards,
HN39
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Old 17th Jul 2009, 22:06
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Ariane wreckage

Talking to a Guyanese pilot friend, many parts of Ariane wreckage have been found over the years in Guyana - usually smaller that the current piece but typically an aluminum/foam/aluminum sandwich.
There have 190+ launches of Ariane rockets since 1979.
LS

Last edited by LifterShifter; 17th Jul 2009 at 22:31. Reason: missing word
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Old 17th Jul 2009, 22:13
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Originally Posted by Razoray
Could anyone please explain the signifigance of finding this IMU.
How it can help in the investigation?????
Maybe the MEMS holds the physical traces of the impact severity and could allow a finer estimation than the other debris ?
Maybe it can give clue on how the airframe failed at the impact ? (why these two pieces are retrieved together)
Maybe it can be proven that this instrument failed in flight ?
... ?
Jeff
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Old 17th Jul 2009, 22:20
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Hope the investigators are as clever as this forum

JD-EE, Thanks for a good description of how they might figure out what happened to the vstab. I hope the investigators are as clever and driven as the people in this and other forums. I still think it's a good idea to simulate different failure scenarios on the ground with an ACARS configured in the same way as on AF447, just to see which ones match the alerts received from AF447.
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Old 17th Jul 2009, 22:30
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TCAS derivation of closing speed

According to #1442:
at 0210, a 3443 event, a TCAS problem (34 is navigation; 3443 is the Doppler system. The Doppler system here is used to measure relative motion of another body, in this case another aircraft, for TCAS)
.

However, if as Graybeard states (#3708) no other aircraft were in transponder range, an out of spec TCAS derived parameter could not have been the reason for the message.

From the FAA booklet, 'Introduction to TCAS ii, Version 7'
Page 7:
TCAS is designed to work autonomously of the aircraft navigation equipment
and

Page 33:
The performance monitor validates many of the inputs received from other aircraft systems and validates the performance of the TCAS processor. These include the own aircraft pressure altitude input and the connection of TCAS to the aircraft suppression bus.
.

This possibly suggests pressure alt as being the most likely cause, but (back to my original point) the existence of this message still questions the 'blocked pitot theory'.

Last edited by VicMel; 18th Jul 2009 at 08:19. Reason: Missing reference
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Old 17th Jul 2009, 22:33
  #3749 (permalink)  
 
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the ADIRUs & the recovered IMU

I am told that there are other IMUs than those of the ADIRUs, located near the CoG of the plane, for the Manoeuver Load Allevation and Turbulence Dumping functions ?
These recovered IMUs do not look like the box shaped ADIRUs ?
Jeff
PS) Well... the following article says that Sensorex IMUs are used both on Airbuses and Ariane's boosters (they are not autopiloted, but it is for trajectographic purposes)
Sensorex a développé un capteur d’une précision extrême déjà adopté par Airbus et Ariane:
Sensorex se positionne sur des marchés pointus. La moitié de son activité est dédiée aux capteurs de déplacement linéaire ; installés avec des applications dans les commandes de vol d’Airbus, dans des machines-outils, des équipements de métrologie ou des installations nucléaires. Elle produit également des inclinomètres, accéléromètres, et autres gyromètres pour l’aéronautique ou l’industrie : afin de suivre la trajectoire d’un booster d’Ariane.
http://www.brefonline.com/numeroERA_affichearticle.asp?idA=2973

Last edited by Hyperveloce; 17th Jul 2009 at 22:48.
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Old 17th Jul 2009, 22:51
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BJ-ENG
Now look at the dark section on the wreckage near the man's head, plus a similar gray ring.
I did try to match the dark colors of the wreckage, as if it were paint, with photo's of AF 330's but could not see how they could match.

I wouldn't think all Ariane's get the same paint job.

I did notice the compound curve of the wreckage which says nose or tail area(of something).

HazelNuts39
Could it be part of an Ariane booster?
Good thinking.

Last edited by ttcse; 18th Jul 2009 at 00:40.
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Old 17th Jul 2009, 23:08
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Flotsam

@BJ

The paint job is a direct match. Look at the blue line and underlying join on the news photo and then the dark kick-up to the left and compare with the top ring of your picture and the kick-up on the logo. Well spotted.

Rgds.

24V
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Old 17th Jul 2009, 23:36
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Meanwhile back at the ranch, AF CEO:

He noted that another AF flight entered the area where AF447 was lost shortly after the doomed A330 last relayed information (ATWOnline, July 3) and the pilot of that following aircraft reported that he crossed a turbulent area that had not been picked up by his radar and "he avoided a much worse [area of turbulence] by manually increasing the sensitivity of his radar." He added, "Flight 447 didn't have the good fortune to encounter that first warning," which might have caused its pilots not to adjust their radar and spot the "very active storm" that the A330 encountered.

"We are going to review the way we use radar," Gourgeon said. "Whether or not that was the cause of the loss of Flight 447, we have to examine every factor and improve all of our procedures and rules. "
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Old 17th Jul 2009, 23:55
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Just now on Bloomberg.

Telegraph also covered this here.

By Ryan Flinn

July 17 (Bloomberg) -- Autopsies of bodies recovered after the June 1 Air France crash in the Atlantic Ocean off Brazil indicate the victims didn’t drown, Agence France-Presse reported, citing investigators.

All 228 people on the flight from Rio de Janeiro to Paris were killed in the crash, and 50 bodies have been pulled from the water. Post-mortems conducted in Brazil show they “did not die by drowning,” said Colonel Xavier Mulot, a spokesman for the French air transport gendarmes investigating the crash, according to AFP.
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Old 18th Jul 2009, 00:09
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Autothrust behaviour with corrupted airspeeds

Is it possible that the autothrust had increased the thrust level trying to compensate declining airspeeds ? (before being disengaged). If yes, is it possible that it was done and not known/noticed by the PF ?
Jeff
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Old 18th Jul 2009, 00:09
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The inside of the Ariane fairing looks unlike the section of supposed fairing that washed ashore. The Ariane fairings for the Herschel-Planck launch had a lattice on the inside. See launch video here:

ESA Portal - ESA en route to the origins of the Universe - images

Without knowing the launch azimuth and the time for jettisoning the fairings, hard to say whether these could readily have washed back to Guyana.
___________________________________

In other news, 43 of the 50 bodies have been identified, including the Captain and three other members of the crew. (Not sure why the body count has dropped from 51 to 50.) Autopsies reveal none of the bodies recovered had drowned, so no repeat of the post mortem findings for several of the Air India passengers.

About 1100 pieces of the plane and contents retrieved; over half of which are already in France (including the VS). Remainder to arrive in France early August.

Sonar search to start soon, and last about one month. The French seem to be pessimistic that they will ever recover the black boxes.
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Old 18th Jul 2009, 00:29
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(Not sure why the body count has dropped from 51 to 50.)
It hasn't - that was a mistake before the DNA analysis made it clear there had only been 50 (souls) found.
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Old 18th Jul 2009, 00:40
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Aguadalte
Further, I understand your explanation of the fuel figures used by AF. I just don't think they are in the spirit of the law.
As that fuel calculation method has been validated by the DGAC and all the aurthorities AF operates into in Europe, your comment is moot.

These guys had one hour and six minutes of flight worth in fuel
Sorry. I should have said : these guys had one hour and six minutes extra fuel in hand to use as they chose.

having in mind the completeness of the flight, provided they would have to re plan, having in mind (EU OPS 1 (again...)
If you looked at the annexes of the BEA report, you'd find the different plans proposed to them : one with a refile possibility, using Borfeaux as initial destination, one at M.81 direct and the last one at M.82 direct, which they decided on, leaving a few passengers behind (Those that the news called "miraculously saved at the last minute" ), because of the extra 900kg or so that the Captain decided on.

A last point, the "arrogant" bit was not addressed to you. You and I may not agree on details but I resent comments by some people whose only link to aviation is a flightsim and think they are entitled to pass judgment on a crew perceived actions...generally with nothing else but prejudice.

Jag6 :
Actually, I think that this statement needs examination.
ADS-C is reporeted "on test" in the Dakar FIR, and generally, it doesn't work.
So HF is used...They're still with Atlantico, with whom they received a positive selcal check...Calling Dakar is altogether another matter and generally, the most successful way would be to monitor the VHF frequency and ask for a relay from a preceding aircraft. so you're stuck in a catch 22 situation : to get an ADS contact, you'd need a positive HF contact with Dakar who then generates an actual flight plan.
And no communication for 25 minutes is certainly not unheard of in those regions.
So what's your point ?
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Old 18th Jul 2009, 01:00
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Lemurian,
The BEA report states that some crew had many problems to contact Dakar ATC via the HF (on 5565 KHz, 6535 KHz, and all the HF frequencies available in the onboard documentation.). At 02:01Z, it was the 3rd and last connection to the Dakar ADS-C to be attempted by the AF 447 crew: would it be possible that these repeated com. attempts may have diverted the PNF from a more carefull met analysis with different weather radar settings approaching the MSC ?
Jeff
PS) is there an explanation for the 3 Atlantico requests (for TASIL estimates) that remained unanswered by the AF 447 at 01:36Z ?
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Old 18th Jul 2009, 01:49
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Hyperveloce

The CPDLC logon is really simple and takes very little time. The pilot enters the ICAO identifier on the ATC LOGON/STATUS page of the CDU and presses SEND. The result does not take continuous monitoring. This page is shown below.


Tha ADS-C contract is set up by the ground station. The flight crew have nothing to do with it.

What we do not know is if AF447 attempted to contact DAKAR on HF. And we will not know until the CVR is recovered. It is possible that any attempts to contact DAKAR may have been recorded on the ATALANTICO tapes, but we don't have those either.

For those interested in CPDLC and ADS-C there is very good coverage available at ATC DL News Home
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Old 18th Jul 2009, 07:07
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Has anyone calculated the likely ocean drift of the piece? Is that distance possible?
Not a specialist myself but it would be truly amazing.

Ariane 5 seems much more likely IMHO.
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