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AF447

Old 15th Jun 2009, 01:24
  #1541 (permalink)  
 
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@JD-EE

Unfortunanly it's called SATCOM Antenna not ACARS Antenna, and this one is steerable.

@Graybeard

Anyhow, going through the downlinked ACARS messages like published in "Der Spiegel" 24/2009 page 129, all warnings happened from 0210Z.

There are 2 failures downlinked with the same time tag:
341115 and 279334 .
Checking the TSM for the operational MSG F/CTL ALTN LAW with failure in 341115 it points to PROBE PITOT 1+2/2+3/1+3 detected by EFCS1 or 2.

279334 does not refer to ALTN LAW, its going direction RUD TRVL LIM FAULT

Referring TSM
TASK 27-91-00-810-822
Disagree of the Pitot Probe Data in the FCPCs



The rest on you guys , I'm out now, let my name out of the game

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Old 15th Jun 2009, 01:47
  #1542 (permalink)  
 
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h3dxb

Thank you, that resurrects some of my prior articles, mostly deleted, that suggest the plane was relatively stable through 0214Z. After that it may have all happened very suddenly. Even with a phased array antenna steering is "slow" compared to the motions of a plane that has gone out of control. (I have written such loops in the past, for reference.)
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Old 15th Jun 2009, 01:56
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JD-EE wrote.....
Now imagine it runs your automobile. Forward means go forward, the further forward the faster. And so forth. Now suppose you hit an obstacle, a speed bump. Your body jerks forward. Your car lurches forward into a crash. This is not a problem if you're sitting comfortably with no sudden accelerations over a small fraction of a G. But add in jerks from turbulence and you might find your arm involuntarily inputting a control surface change that was out of the range the plane could tolerate."


This is exactly my point....not the joystick receives feedback but that in this situation if factors are as assumed who would have a steady hand in trying to recover this a/c in direct law. Any little bump or quick movement would translate rather quickly to the joystick if the pilots hand is on it....not as easy to inadvertently shove the control column full forward in turbulence when "hand flying" it.
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Old 15th Jun 2009, 02:12
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Found this article on the A320 side stick controller. Claims Captain and FO can cancel each other out.

A320 sidestick description + references (Re: Airbus safety)

Remember the F-16 side stick didn't move at all on the prototype, but it moves slightly now with artificial feel. and the forearm is supported. Forward travel is extremely limited though because they found under negative g, the pilot would over control.
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Old 15th Jun 2009, 02:13
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JD-EE, pot #1544 and on.

Your concern about turbulence bumping the stick, with or without hand attached, around so much that the inputs would be enough to exceed aircraft structural limits ? NO WAY.

Side stick steering is accurate enough to keep an F-16 aimed within a few mils of a target, while flying at 500 kts at low level in very bumpy conditions (1 degree is 17.5 mils).
And in the A-320 it is comfortable enough to enable greaser landings in 30 kt crosswind conditions that cause a 1.25 g bump at 32 ft radio altitude and 2 seconds later a 0.8 g bump at 25 ft RALT.

BOAC #1546.
I agree that flying without any attitude refernce would make the task at hand nigh impossible, but what about Inertial Ref systems 1 and 3?
Somewhere in the endless list of postings I have seen the interpretation that IR2 was reported as failed by, amongst others, IR1 and IR3.
Apparently some (many?) people had interpreted the involved data format of ACARS as a report of failure of IR2 and IR1 and IR3.

Mad Flt Scientist #1563.
I agree with you that the ADIRU parts are the Inertial Reference part and the Air Data part. I do not think that in failure modes the static and dynamic pressure sections of the Air Data part are treated as separate entities. I am not sure about the Angle Of Attack Signal - whether that would also be rejected - have to go back to the books on that one.

By the way, why not throw in a new subject. Isn't it a great coincidence that together with the pitot static failures, another totally unrelated system failed, IR2?
Could it be that, troubleshooting ADR2, by accident ADIRU2 was switched OFF? I always found that a very easy to make error in the A-320.
In everyday life you always manipulate the rotary selector, never the ADR push button, the system is called ADIRS and failure of the Air Data (Computer part) of the ADIRU is annunciated on ECAM as
NAV ADR2 FAULT.
Now that looks very much like ADIRS, which you always manipulate via the rotary selector (with shuts down the IR part).

Edit: corrected the mil specification)
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Old 15th Jun 2009, 02:23
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Not implying causality in any way shape or form by providing these links.

Whilst looking for something else, I read through the systems linkages/interactions (discussed in the first link) and am wondering if it might provide an answer to Greybeard, BOAC and Capt Crunch’s questions regarding sys links between some of the input data to ISIS.

http://www.casa.gov.au/airworth/airw...0/a330-095.pdf

Airbus Model A330-200 and -300 Series Airplanes, and

I am not certain so no comment.

I am sure this has been asked, but I cannot find a solid reference. Was AF447 equipped with Northrop-Grumman (formerly Litton) Air Data Inertial Reference Units (ADIRUs), part number (P/N) 465020-0303-03ZZ (with ZZ from 09 up to 16 inclusive), or the Honeywell units?

EDIT: TIME

According to Airbus spokesman Justin Dubon :-

"manufacturer Northrop Grumman makes the ADIRUs for Qantas, and Honeywell for Air France."

Last edited by The Chaser; 15th Jun 2009 at 13:08. Reason: Confirmation from Airbus of ADIRU Manufacturer
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Old 15th Jun 2009, 02:38
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Chaser

I recall reading earlier in this thread that AF447 had Honeywell ADIRU's fitted
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Old 15th Jun 2009, 02:45
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Originally Posted by TWT
I recall reading earlier in this thread that AF447 had Honeywell ADIRU's fitted
this is the only post I could find which appears to contain that information. It's hardly conclusive.
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Old 15th Jun 2009, 02:45
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TWT Thank you.

EDIT: See above post#1569 re: Airbus confirmation of Honeywell being the manufacturer of Air France's A330 ADIRU's

Would both ADIRU models output data in the same way/configuration to linked systems?

Last edited by The Chaser; 15th Jun 2009 at 13:19. Reason: Question re ADIRU manufacturer answered
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Old 15th Jun 2009, 02:51
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Graybeard said:
Without the FDR to bring in a surprise, the majority of a civil jury (US law) would conclude that Thales, Airbus and Air France share in the negligence that allowed this fleet to contine after five serious incidents caused by icing of obsolescent pitot tubes. I don't see why anyone would try to thwart recovery of the FDR. The evidence from it could hardly be more damning.

GB
Statistically, A330's are good safe airplanes. It's just that we who desire that trend to continue, wish for meaningful successful mods to the factors responsible for this tragedy. And we are just a rumor board, NOT an investigative body. We have only skimpy info available to us; therefore any speculation by us here is strictly personal opinion only.

Graybeard, I'm not sure that negligence is the right word. Industry wide "Overconfidence in automation" is the term I would use, and is the non-criminal culprit that I suspect. Whether that be an operational training attitude, or a design issue (I can't know that, I've never flown the A330 or a FBW aircraft) or a combination of a whole lot of things (factors), the fact is that a problem likely exists, and all parties appear to me to be doing something about it. Did the past fixes work? Doesn't look like it.

I'm sure its most likely the crew was current and qualified. But what about being able to fly partial panel, at night, in weather, with nothing but the whisky compass and a flashlight in your teeth? Could you set say 8x% N1 and make a gradual 180 on the Whiskey compass with no attitude, or just using the IRU true heading in rough weather? I don't know if it can be done....

We never really train for that one do we? Because, before now, it was believed it was unlikely to ever happen. But by the same token, for a long time, we never believed volcanos could take out all four engines, and before that we never believed in a thing called microbursts after a pilot made a so-called "bad" landing.

Right?

My humble opinion is that simulators are marvelous training devices, but they are no substitute for hand flying the climb and descent and hand flying a manual landing on a daily basis in the actual aircraft far away from the "Magic Kingdom" (the sim.) Without practice in this art of manual flying (occasionally all the way up to altitude and then S&L for a few minutes.) crews don't stand a chance when "Otto" gives up at the worst possible time.

There's only one man we can turn to in an uncertain situation like this. A good Union Man. President Obama was wise indeed, to appoint the former head of the Air Line Pilots Association to head the FAA.

I would call on the very-capable, just appointed, FAA Administrator: Captain Randy Babbit, to review the over-reliance/distraction with automation that crews now face, and make sweeping changes to the industry in this regard.

Fraternally,

Captain Crunch


.

Last edited by Captain-Crunch; 15th Jun 2009 at 04:29. Reason: spelling correction, form
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Old 15th Jun 2009, 02:52
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Mad(flt)Scientist, "Question: does the entire ADR section of an ADIRU "fail" as one unit? That is, having detected that it is producing "unreliable" airspeed data (through the ADR DISAGREE method) is the entire ADR output regarded as suspect by other systems?"

The communication from the Air Data (Module, Computer) to the transponder, for example, is on an Arinc 429 serial digital data bus. There are several words transmitted in sequence, each with its own identifier and validity state. CAS, IAS, TAS, SAT, Pressure Altitude, Baro Altitude, Vertical Speed, etc. will be on the bus.

The transponder will pick off Pressure Altitude, and ignore the rest. The ADC transmits all words repeatedly. If the airspeed goes invalid, for example, Fail Warn will be indicated in the Sign Status Matrix of that word.

Therefore, an iced pitot will have no effect on the transponder or any other device that uses Altitude, nor on the TCAS, which is even farther removed.

GB
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Old 15th Jun 2009, 03:06
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swish 266 - post 1510 -
"The more important thing is WHY IT HAPPENED!
WHY AF477 ENDED UP BEING WHERE THEY SHOULDN'T HAVE BEEN IN THE FIRST PLACE?
This is the million $ question!
Why didn't they deviate like IB or LH?"
*******************

The IR satellite picture shows cold temperatures for hundreds of miles. IB supposedly deviated 30 miles from the track which isn't much and would put them in the same airspace on the IR picture.

Has anyone stated what exact route AF 447 took? Perhaps they were deviating just like the Iberia flight.
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Old 15th Jun 2009, 03:11
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misd-agin

Nobody knows. And the supposed positions at last ACARS report seem to be conjecture. Two quite separated locations have been published for it.

{o.o}
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Old 15th Jun 2009, 03:11
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The Chaser:

Though not a definitive answer this would make me think Honeywell.

"The NTSB said, they have accepted an invitation by the BEA to assist in the investigation and have dispatched Bill English as their representative joined by engineers from the FAA, General Electrics (manufacturer of the CF6 engines) and Honeywell."
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Old 15th Jun 2009, 03:16
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Originally Posted by Graybeard
Mad(flt)Scientist, "Question: does the entire ADR section of an ADIRU "fail" as one unit? That is, having detected that it is producing "unreliable" airspeed data (through the ADR DISAGREE method) is the entire ADR output regarded as suspect by other systems?"

The communication from the Air Data (Module, Computer) to the transponder, for example, is on an Arinc 429 serial digital data bus. There are several words transmitted in sequence, each with its own identifier and validity state. CAS, IAS, TAS, SAT, Pressure Altitude, Baro Altitude, Vertical Speed, etc. will be on the bus.

The transponder will pick off Pressure Altitude, and ignore the rest. The ADC transmits all words repeatedly. If the airspeed goes invalid, for example, Fail Warn will be indicated in the Sign Status Matrix of that word.

Therefore, an iced pitot will have no effect on the transponder or any other device that uses Altitude, nor on the TCAS, which is even farther removed.

GB
OK, but in this case is it not the FMGEC that's calling the ADR DISAGREE, not the ADIRUs themselves? After all, an iced pitot may present no useful symptoms to the individual ADM or ADIRU that can be used to detect the possible problem. It's only at a higher, integrated, level where the comparisons can be carried out between the different ADIRUs and a problem possibly identified. In this case the ADIRUs may all have been claiming their data was valid, since no system failure had occurred. (And as I understand it there's no ADIRU failure on the ACARS list - which implies the boxes themselves thought they were ok; it was the customer systems that identified the problem.

If the FMGEC (or whatever its called?) is spitting out an ADR DISAGREE, is that going to then cause either the ADR parts to consider themselves potentially invalid, or other systems to do so? (The FMGEC in effect is "policing" the ADR data in that model)
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Old 15th Jun 2009, 03:18
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FE Hoppy (post 1246), Lost in Saigon(post 1248)(thanks for the picture), and ttcse(post 1251) -

A poster stated that the AF vertical stabilizer had no fluids around it unlike the A310 vertical stabilizer. The difference might be that the A310 vertical stabilizer picture could have been taken as soon as 9 hours after the accident. Based on the picture the sea state seems fairly calm.

The AF 447 vertical stabilizer was not found for several days. Reports stated that the search was difficult due to weather and sea conditions.

Those differences may, or may not, explain the different levels of POL's near the vertical stabilizer.

Right now it's too premature to state the vertical stabilizer must have seperated inflight.
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Old 15th Jun 2009, 03:28
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Originally Posted by 'EMIT'
BOAC #1546.
I agree that flying without any attitude refernce would make the task at hand nigh impossible, but what about Inertial Ref systems 1 and 3?
Somewhere in the endless list of postings I have seen the interpretation that IR2 was reported as failed by, amongst others, IR1 and IR3.
Apparently some (many?) people had interpreted the involved data format of ACARS as a report of failure of IR2 and IR1 and IR3.

Surprised the following post is not avail anymore ?




Regarding the sidestick, whatever the law, the less you touch it, the better.
Actually very easy to overcontrol.
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Old 15th Jun 2009, 04:49
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loss of vertical surfaces in Canadian fleet prior to
AA A300,
What the hell? I worked for them and the only loss I'm aware of is an A320 vertical stabilzer clipped by another aircraft. Replacement flown in by Airbus Beluga. Interesting day.
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Old 15th Jun 2009, 05:51
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A "maintenance professional" is one helluva long way separated in so many ways from an engineer, or a materials scientist that I'm surprised anyone would give any weight to their opinion.

A lot of laypersons (including personnel employed to bolt and unbolt things on things that take to the air) seem that they just can't hurdle the concept of a non-metallic aircraft/parts. I even read someone equating keel breakages on super-maxi yachts to Airbus design flaws....

Not even close!
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Old 15th Jun 2009, 06:38
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Rollingthunder, I think the poster meant the Air Transat case, where the entire rudder broke off while cruising on autopilot. That was in 2005, long after AA587.

AirDisaster.Com Accident Photo: Air Transat A310-308 C-GPAT

This was one of two incidents (the other was a Fedex aircraft) that finally solved the A300/310 rudder problem; which was found to have been not any basic weakness but delamination caused by leaked or spilled hydraulic fluid.
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