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jauh 5th Jun 2009 03:09


Does the ACARS line item ISIS at 0211 indicate a fault in the Integrated Standby Instrument System, or that it is what is remaining? I suspect the former, please confirm.
Type=FLR (Fault Report)

GE90115BL2 5th Jun 2009 03:14

I'm not an Airbus Pilot but.

The fault in the ISIS doesn't mean the whole display was inop? surely the attitude info would have been ok?
Might the fault mean that the IAS or ALT info on the ISIS was faulty?

If so then the crew should still have had attitude info at the very least. ( all be it on a small ****ty display )

PJ2 5th Jun 2009 03:36

Lemurian, superb sleuthing work; Machaca, superb postings. I'll take a look in the AOM and other resources I have regarding these messages.

Some preliminary information on these messages:

I believe these are all ECAM warnings or cautions. Maintenance messages are termed "Category 3" and are not displayed to the crew but are sent to the airline maintenance group. All these messages would have been displayed on the lower ECAM.

The ATA System Chapter numbers are on the far left and also at the beginning of the text under the label "Libelle succint du message".

The following is a specific A330-200 MEL ATA Chapter list for referencing the systems from which these messages are generated. This is not the Master MEL but may be tailored to one or another airline. Some chapters are missing. However, no chapters referenced in the ACARS document under discussion are missing.

The first message for the flight is second from the bottom, (as Lemurian points out, the bottom two are from the previous flight, AF 444):

Example:
22 10/06 WRN WN0906010210 221002006AUTO FLT AP OFF 09-06-01 AF 447

This is an ECAM warning indicating that the autopilot is off. It is a red warning. It is standard that red warnings require immediate crew attention but the warning in and of itself does not indicate a serious problem.

Of immediate interest is the absence of any ATA Chapter 24, Electrical System messages.

For ATA 34 and ATA 27 items at 0210Z, "EFCS" is Electronic Flight Control System, and "AFS" is Auto Flight System. ATA "3411", as far as I can determine, is "AOA sensor" but I cannot determine what the numbers following "3411" mean - perhaps further details in the AF MEL, (since clarified below, thank you).

With reference to ATA 3410 "ADR Disagree" caution. The aircraft AOM states that:


...this caution is triggered by the PRIMs, when they only use 2 ADRs, and these 2 ADRs disagree. This may occur, when :
One ADR has already been selected OFF by the pilot, or

One ADR has been eliminated by the PRIM, without any caution, because it deviated from the others.


The procedure then is to check the airspeed on both PFDs, and on the standby airspeed indicator. If there is NO disagreement, there is an AOA discrepancy and if there is a discrepancy the ADR Check procedure is applied. The aircraft is in Alternate Law at this point.

Note: Following an ADR DISAGREE, detected by the PRIMs, ALTN law is latched. Resetting the PRIMs by using the pushbutton does not allow normal law recovery.




The ATA 34 message concerning the ISIS is followed by two zeros which generally means the fault is not specified, too general to specify or too numerous to specify. We cannot conclude anything from this information but the fact that there was a fault with the ISIS system. The same holds true with any ATA message where the fifth and sixth digits are zeros.

At times, the second to sixth digits do not match the documents I have referenced. Each airline may have it's own MEL sub-references, I don't know.



ATA 21 is the Air Conditioning Chapter. This last message is indicated as an ADVISORY level message, (appropriate text is pulsing bright/dim green on the lower ECAM. However, the "Typ" (type) of message is "WRN", (Warn). I have no means to interpret this. There is no indication of cabin pressure loss. That is all this message means - that there is no message.



There are no "Stall" warnings in the available messages.



WARNING:
While this information is more than has been available to date, it is not sufficient to surmise or conclude events. It is what it is and nothing more. Because this information was taken off a television news program and not the source documents themselves as provided by any authority, it may be incomplete, or partially or wholly incorrect.



ATA Chapters:


AIRCRAFT GENERAL
05 Time limits/Maintenance chks
06 Dimensions and areas
07 Lifting and shoring
08 Levelling and weighing
09 Towing and taxing
10 Parking and mooring, Storage and Return to Service
11 Placards and Markings
12 Servicing

AIRFRAME SYSTEMS
20 Std. practices-airframe
21 Air conditioning
22 Auto flight
23 Communications
24 Electrical power
25 Equip/furnishings
26 Fire protection
27 Flight controls
28 Fuel
29 Hydraulic power
30 Ice and rain protection
31 Indicating/Recording Systems
32 Landing gear
33 Lights
34 Navigation
35 Oxygen
36 Pneumatic
37 Vacuum
38 Water/waste
45 Onboard Maintenance Systems
46 Information Systems
49 Airbourne Auxiliary Power

STRUCTURE
51 Standard Practices and Structures
52 Doors
53 Fuselage
54 Nacelles/pylons
55 Stabilizers
56 Windows
57 Wings

POWER PLANT
70 Std. practices-engine
71 Power plant
72 Engine
73 Eng. fuel and control
74 Ignition
75 Air
76 Engine controls
77 Engine indicating
78 Exhaust
79 Oil
80 Starter

greenspinner 5th Jun 2009 03:52

3411 is sub chapter ATA i.e. 34-11= SENSORS, POWER SUPPLY & SWITCHING
Beware that messages are not in chronologicaly display on this display.
The last one is in fact Advisory at 0214 ATA 2131 PRESSURE CTL & MONITORING, Identifier ATA 21 Air CONDITIONING.

jauh 5th Jun 2009 04:05


ATA "3411", as far as I can determine, is "AOA sensor" but I cannot determine what the numbers following "3411" mean - perhaps further details in the AF MEL.
2131 Cabin Pressure Controller
3410 Environmental Conditions
3411 Pitot-Static System
3412 Outside Air Temp
3422 Directional Gyro & Ind.
3443 Doppler

(JASC Standard Codes)

Captain-Crunch 5th Jun 2009 04:26

Machaca, great image work as always.

PJ2, I presume your source for ATA section codes is the pilot's MEL? If so, did you type that from the onboard MEL?

That's the POI approved version specific to a particular airline, is it not?; an abbreviation of the Airbus Master MEL. If so, it's a legal dispatch reference, and not a maintenance trouble shooting reference. Unless I am mistaken, it only addresses dispatch concerns, such as Air conditioning that your POI permitted you to defer, whereas, the full volume derived from the type certificate data sheets in France may be very different and the same numbered section may include both air conditioning and pressurization items (just as an example) even though the section is called "Air Conditioning" on both.

Your posts are extremely good, but your list starts at section 5, and omits sec 13-19, 33-44, 50, 58-70 etc if those sections exist.

To draw conclusions from your list seems wrong to me. We should be using the specific ATA section and item number from the actual maintenance volume. (As an A&P) this is what I was taught.

For example you said:

ATA 21 is the Air Conditioning Chapter. This last message is indicated as an ADVISORY level message, (appropriate text is pulsing bright/dim green on the lower ECAM. However, the "Typ" (type) of message is "WRN", (Warn). I have no means to interpret this. There is no indication of cabin pressure loss. That is all this message means - that there is no message.
I'm not convinced yet that "there is no message" as you said.

Cheers,

Crunch

PJ2 5th Jun 2009 04:46

Captain-Crunch;

PJ2, I presume your source for ATA section codes is the pilot's MEL? If so, did you type that from the onboard MEL?

That's the POI approved version specific to a particular airline, is it not?; an abbreviation of the Airbus Master MEL. If so, it's a legal dispatch reference, and not a maintenance trouble shooting reference. Unless I am mistaken, it only addresses dispatch concerns, such as Air conditioning that your POI permitted you to defer, whereas, the full volume derived from the type certificate data sheets in France may be very different and the same numbered section may include both air conditioning and pressurization (just as an example.)

Your posts are extremely good, but your list starts at section 5, and omits sec 13-19, 33-44, 50, 58-70 etc if those sections exist.

To draw conclusions from your list seems wrong to me. We should be using the specific ATA section and item number from the actual maintenance volume. (As an A&P) this is what I was taught.
Many thanks - yes, you are correct up to a point but the MEL I have always referenced and the different MEL I now reference provides for both pilot and maintenance actions. Perhaps a bit of a disconnect in understanding but to me, the MEL on board the aircraft should differ only in appropriate references for the airline's specific aircraft but should not include information that is only available to Maintenance. Not sure if this is what you meant.

I agree that drawing conclusions from the list is wrong. The comments I include after the PRIM 1 fault are from the AOM. I should have mentioned that and will edit the post to do so. For the others I specify that no conclusions may be drawn and warn against same.

Thanks for your comments. We now have a bit to work with.

PJ2

lomapaseo 5th Jun 2009 04:57

Now with two separate threads running (R&N and Technical Questions) I'm not sure where to post repsonses. If I were reporting News or Rumor I would have thought here. However I were to respond to an technical analysis and discussion of this news I would have thought in the thread running in the technical section.

Perhaps the moderators can sort this out.

The ACARs is not a crash recording device and its useful information is appropriate mainly to post flight maintenance actions. Somewhat akin to the FADECs on engines. However those that design and configure the particular device (AF & Airbus) may be able to work the design configuration logic tree way beyond our simple guestimates.

Significant to me is the suggestion that ACARs confirms a change in flying logic that would compel the pilot to read his base instruments and fly the aircraft in a controled manner while in turbulence.

I believe that most pilots would have preferred that the aircraft fly itself while in turbulence.

If the reversion in flight control law was turbulence alone (no initial structural failures) then it is important to consider whether the aircraft was allowed to operate outside its design envelope (flight speed). If the airspeed was not controlled sufficiently this could have led to upset and flutter failures and ultimate beakup over a time period.

Unfortunately investigations along this line will require more than the recovery of a few bits of debris.

Captain-Crunch 5th Jun 2009 05:04

Thanks for clarifying PJ2,

Sorry to be so picky. But this is a great example of why nobody should be excluded from a rumour site such as PPRUNE imho. I see now, that a kind mtc guy has provided confirmation that the last message 2131 is indeed a Cabin Pressure Controller issue.

You appear to be correct however, PJ2, that it seems there are no electrical bus faults in this list so far. So, exercising good CRM, I defer to you, and will abandon my lighting bolt theory [causing electrical grief] (at least from now.) :-)

Please forgive my interruption with your train of thought.

Crunch

(As an aside, I think the Mod's here do a fantastic job, imho. Thanks guys.)

etesting2000 5th Jun 2009 05:13

machacka, jauh, captain crunch, pj2, excellent information. Thank you. Those of us no longer on the inside count on viable information from here. Please don't cut us out. I'll research my questions in advance and make them relavent. Question, are faults to this degree taught in simulator or is this an extraordinary event? What I read in that transcript sounds like real bad doodoo.

Nero1352 5th Jun 2009 05:18

The sequence of ACARS messages shows at 0212 an ADR disagree message.
This massage does not say anything about the number of ADRs that disagreed. Under many conditions the system cannot isolate the faulty ADR. The consequences would be that many systems that rely on inputs from the ADR will show faults (TCAS, Cabin Pressurization Control)) or disengage (AP,ATHR) and the F/CTL system would revert to a degraded mode.
The crew has to find out which indication they can trust and what action to follow. The Airbus 330 OM-B gives an extensiv description of the problems under the title "MISC Unreliable speed indication/ADR Check"

Posible reason for the ADR disagree: damage to the radom by lightning or hail.

PJ2 5th Jun 2009 05:30

Captain-Crunch;
The intervention's always welcome, thanks; ya gotta be picky and then take it from there.

I'm still trying to reconcile ATA 341115; my MEL has 341101 with the AOA item as described, (thus the loud-and-clear caution about interpretation), but I don't have a "341115" and can't find "pitot/static" systems, ergo, they are all "no-go" I must assume.

grimmrad 5th Jun 2009 05:33

Turn?
 
No one seems to have asked why the original debris reports were in positions that didn't follow any of the basic rules mentioned above.

---------------------------------------

I allowed myself to ask in the earlier forum without getting a response - couldn't the crew have decided upon failure of systems (e.g. the WX radar) and given their current environment to turn back to the nearest airfields, i.e. in Southamerica? Someone mentioned this as a wise choice in this case and good airmanship. Thus the latest indicated (transmitted) position would indeed be somewhere else than the actual crash side if a malfunction occurred...?

Disclaimer: Not part of your industry, interested SLF (=annoyance)

PJ2 5th Jun 2009 05:37

etesting2000;

Question, are faults to this degree taught in simulator or is this an extraordinary event?
In routine, recurrent training, no, they are not. They can show up on the final ride for a brand new captain being promoted but there is no pass-fail, only the experience.

The sim rides which establish both aircraft and instrument flying competency and have full pass-fail outcomes, are, in my experience, heavily scripted and known and prepared for in advance with advance workbooks and so on. The process is, in my view, very good and appropriate. One simply cannot train for what are extremely rare moments when ultimately one must utilize every ounce of one's experience, training, skill and intuition. Al Haynes and his crew were in such a situation as I'm sure we all know. These issues are front and center in our industry right now with Madrid, Colgan and a few others.

'nuff drift.

fqis 5th Jun 2009 06:18

Adirus ???
 
from the warning list , all the systems listed requires an input from ADRIUS ,i dont understand why all the media talking about electrical problem while i dont see any warning related NO ATA CHAPTER 24 , from experience , i ve never seen so many messages in one POST FLIGHT REPORT , but some of them are triggered from time to time , and most of the time we reset the related ADIRU to solve the pblm .

bubbers44 5th Jun 2009 06:28

AF would not have flown into this large cell if they had an opperable radar. Maybe the radar lost sensitivity and made that cell look benign. I had an MD80 flight one day with a radome with a lot of cracks and delamination that was worthless in bad weather. I finally gave up and asked the controller for a suggested course. He said it doesn't really matter because you are in the middle of it. Thank God that is not the norm but I can see AF having the same situation.

vapilot2004 5th Jun 2009 06:48

Just heard from a qualified engineer
 
ACARS maintenance messages are timed stamped according to the event and have nothing to do with the transmission time.

Said engineer will have a look at the ACARS report tomorrow.

Captain-Crunch 5th Jun 2009 06:54

Good point Bubbers44,

The acars messages seem consistent with what you might expect to see with cell penetration and heavy icing covering up all the pitot probes, and ports, causing the loss of data to nav systems and to flt control systems, followed by upset, followed by loss of cabin pressure control (down low)

BREAK

PJ2, I don't have the maintenance ATA fault manual in front of me, but I would guess acars code 341115 would likely decode this way: 34=Nav ATA section, 11=subsection (item) pitot static, 15 = specific status condition or report.

Just a guess.

Any mtc guys wanna tell us what piece of equipment this is and what it's status is?

PJ2 5th Jun 2009 07:00

Thanks Capt'C - it's important, relatively speaking, as 3411 specifies the AOA sensor in my document but in the JASC document it's "pitot-static".

Captain-Crunch 5th Jun 2009 07:21

PJ2,

yeah, your document is good until t/o roll begins. So it's tailored to only address no-go items, or alternatively items that the POI (Principle Operations Inspector) or his equivalent in France has determined that you deserve to get relief on.....your ETOPs inventory audits, etc, etc, qualify you to have that item put in your document. (defered mtc items.) For example, ETOPs was denied us because our spare parts inventory sucked, so our MEL was way different than other airbus operators.

After t/o roll ATA mtc books take over which are much amplified. However, mtc still references Master MELs en route in the interest of having parts and people prepared at the next through stop to continue, if necessary with deferred equipment for x days. Since at that point they know the MEL will take over at block in.

That's how I understand it. I know that MEL interpretation is one of the most disputed aspects of airline life. :-)

But that's why they pay us the big bucks, huh?

C


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