AF447

[mm43]

Hyperveloce

Strange, the speed between ORARO and the last known position at 02:10Z is much lower than between the other markers ! (435 kts versus 470 kts ?!).

The positions plotted on Google Earth are as follows:-

TASIL 4°00'18"N 29°59'24"W
LKP 2°58'48"N 30°35'24"W
ORARO 2°14'48"N 30°55'24"W
0200 1°48'36"N 31°09'06"W
0150 0°39'54"N 31°45'24"W
SALPU 0°26'36"N 31°52'36"W

Even though the Last Known Position (LKP) is timed at 02:10:34, that time is the logged time of the Ground Station / Aircraft 'handshake'. The nominal time is assumed to be 02:10:00z. AOC reports take precedence over maintenance traffic, and I presume the 0210 one was slotted into the sequence immediately following the receipt of a message being transmitted.

The positions are shown with a precision of 0.1', though it should be noted that the LKP is only accurate to 0.01° - or +/- 1824 feet (556m).

ORARO to LKP is 024.4°T x 48.3NM
02:03:50 ORARO ~ 02:10:00 LKP = 48.3[1/(6.1667 / 60)] = 469.9KT
02:03:50 ORARO ~ 02:10:34 LKP = 48.3[1/(6.7333 / 60)] = 430.4KT

I'm happy to stand corrected if anyone is able to prove the LKP time-stamp is different. The original BEA graphic shows the LKP as 0210z.

mm43

[Will Fraser]

mm43
Just two minor things, one a bit picky.

There is a last position, it is reported, not known.

You assume the route between penultimate position and ultimate position to be a straight line, that is not at all known. If there were other course "changes" between the last two points, the speed could be a great deal higher. IMO. Which is to say, not constant. Fluctuating.

Will

[mm43]

Will Fraser

You assume the route between penultimate position and ultimate position to be a straight line, that is not at all known. If there were other course "changes" between the last two points, the speed could be a great deal higher. IMO

Not the case at all. I was responding to a point made by Hyperveloce, and it involved the speeds he had deduced, ie. time v distances. The times were the mute point. Your point of course is valid!

You will remember that I have previously said that we know nothing about the 0210 Last Known Position - AF and the BEA know a lot more. When or if a deviation occurred and all the other facts that go to make up that 3D position have been with-held.

I am more inclined to believe it happened as a result of an upset - but even that is speculation.

mm43

[JuggleDan]

Why has crew subtle incapacitation or a deliberate malevolent act seemingly been ruled out... when we have no idea at all what was taking place in that cabin, or cockpit.

Most of the reflexion going on is based on what we have: ACARS messages. I guess "crew subtle incapacitation" looks like a far fetched explanation for these messages.

[Razoray]

Actually it was speculated early on that it was a terrorist attack......famous terrorist on board or something or other.......crime fighter?

spooky spooky...some one slips into flight deck during change over..........done deal!

I dont know???

[augustusjeremy]

more speculation

All those warnings begin

The crew guesses by turning ADR1 off. Only PRIM2 detects the move.

The ISIS, which is fed by ADR1 input, complains.

But the culprit was IR2 which generated wrong ADR2 output.

Then... (fill in the blank)

edit: the crew guesses by turning ADR1 and IR1 off... So that there is no more comparison to generate a NAV IR2 FAULT ECAM warning, as only IR3 remains "healthy"..

[JD-EE]

GB,

Way early, they ruled out suspected terrorists, after mentioning two possible.

Did they explicitly rule out all acts of terrorism or only a terrorist bomb? I can see ruling out bomb. I am not sure ruling out terrorist is sensible unless there is an ACARS sort of message that goes out with a really simply button press by anybody in the cockpit.

JD-EE

[RetiredF4]

Quote:
Why has crew subtle incapacitation or a deliberate malevolent act seemingly been ruled out... when we have no idea at all what was taking place in that cabin, or cockpit.

Quote:
Crew incapacitation could explain why AF447 flew into the CB cell on AP rather than deviating around it, and maybe explain why they didn't respond to HF Comms.

I raised this question before , but it was probably not the apropriate time, so it got deleted.

"At what time can we confirm the last positive action of the crew in the cockpit"?

regards

[auraflyer]

I raised this question before , but it was probably not the apropriate time, so it got deleted.

"At what time can we confirm the last positive action of the crew in the cockpit"?

regards

2:01.

According to sec 1.16.2.1 of the BEA report, AF447 made 3 attempts to connect to Dakar ADS-C: at 1:33, 1:35 and 2:01. (These were rejected because of a flight plan absence or mismatch.)

[Me Myself]

Why has crew subtle incapacitation or a deliberate malevolent act seemingly been ruled out... when we have no idea at all what was taking place in that cabin, or cockpit.

Deliberate malevolent act ???????????? Like they were muslim fundamuntalists ??????????? This is Air France mate, or is it that France and Egypt are the same to you ???
As to incapacitation, you've got your answer on the post above.
Are you for real ??

[Hyperveloce]

Last positive action of the crew ?

Originally Posted by RetiredF4

"At what time can we confirm the last positive action of the crew in the cockpit"?

Hasn't the plane been piloted till the end ? what is the probability for a non piloted/non pilotable plane to impact the surface, on his belly, "en ligne de vol", after a 35 000 ft rapid descent ?
Jeff

[RetiredF4]

@Hyperveloce

Quote:
Originally Posted by RetiredF4
"At what time can we confirm the last positive action of the crew in the cockpit"?

Hasn't the plane been piloted till the end ? what is the probability for a non piloted/non pilotable plane to impact the surface, on his belly, "en ligne de vol", after a 35 000 ft rapid descent ?
Jeff


The Question ist not what we know, but what we do not know. And we do not know yet why it happened , only how it ended. There are a lot of probabilities and possible reasons, and no one has prooved itself yet. And why should an aircraft falling out of the sky not hit with the belly first? I don΄t think that from the mode of impact we can conclude the aircraft being piloted until the point of impact.

So if i understand correctly, the attempt to contact ATC at 1:33, 1:35 and 2:01 needed deliberate action of the crew at those given times, it has no automatic repeat function in case of a failed contact attempt?

Anything else know after that given times?

FR

[augustusjeremy]

since the beginning

Yes, Aguadalte...
You were right since the beginning.

The question is: Did they turn on ADIRU1 again ? Wouldn't it take some time to realign ? And how would it realign without trustful IR data (as the other two IRs were probably disagreeing ?)

The text you posted earlier in this forum:

RED OEB – RED OEB – RED OEB – RED OEB – RED OEB – RED OEB – RED OEB
Issued by STL
File in FCOM Vol 3
OEB N°: 74/4 DEC 08
Associated with QRH OEB PROC N°: 74/4
- This OEB covers a significant operational issue. Non-compliance with this OEB should have a significant impact on the safe operations of the aircraft. The Operators shall distribute its content to all flight crews without delay. An extract of this OEB is provided for insertion in the QRH.
- It is strongly recommended that all Operators accelerate the incorporation of all corrective Service Bulletins as soon as they are available.
SUBJECT:
IR FAILURE OR ATT FLAG ON PFD
APPLICABLE TO:
All A330 aircraft fitted with NORTHROP GRUMMAN – LITTON ADIRU
CANCELLED BY:
TBD
R
REASON FOR ISSUE 4:
RRRR
The previous OEB revision requested to de-energize the affected ADIRU if the IR and/or ADR OFF lights did not illuminate. The OEB procedure is now revised in order to recommend that the IR mode rotary selector be set to OFF in all cases in order to address all identified failure cases.
Page 1 of 5
Operations Engineering Bulletins are issued by Airbus as the need arises to quickly transmit technical and procedural information. They are distributed to all FCOM holders and to others who need advice of changes to operational information.
Information in this bulletin is recommended by Airbus but may not be approved by Airworthiness Authorities.
If the procedures contained in this OEB differ from the procedures in the AFM, the AFM remains the reference.
OEB N° Page 2 of 5
74/4
REASON FOR ISSUE:
This OEB is issued in order to provide a procedure enabling to mitigate the probability of occurrence of a sudden nose down order.
EXPLANATION:
An A330 aircraft experienced a sudden nose down order during cruise. This order was preceded by an automatic autopilot disconnection and triggering of the NAV IR 1 FAULT ECAM caution.
Investigations highlighted that at the moment of the event the ADR 1 was providing erroneous and temporary wrong parameters in a random manner. This abnormal behavior of the ADR 1 led to several consequences such as unjustified stall and over speed warnings, loss of attitude information on the Primary Flight Display, several ECAM warnings.
Among the abnormal parameters, the provided Angle of Attack value was such that the flight control computers commanded nose down movement.
The aim of the following procedure is to isolate both the IR and ADR when an IR is detected faulty in order to prevent the ADR from providing erroneous data to other aircraft systems.
TO BE CONTINUED ON NEXT PAGE
PROCEDURE:
RRRR
OEB N° Page 3 of 5
74/4
RRRR
• If all ADIRU operative before failure:
If one IR is self detected faulty or if the ATT red flag is displayed on the Captain or First Officer PFD, the affected IR and the corresponding ADR must be disconnected.
NAV IR 1(2)(3) FAULT, or ATT flag displayed on CAPT (F/O) PFD
-IR (affected) pb …………………………..…… OFF
The affected IR is the one self-detected faulty or supplying the PFD displaying the ATT red Flag.
The OFF light may not illuminate
-ADR (corresponding) pb ………..…………… OFF
ADR 1 corresponds to IR 1.
ADR 2 corresponds to IR 2.
ADR 3 corresponds to IR 3.
The OFF light may not illuminate
-IR (affected) MODE rotary selector ……….. OFF
The IR mode rotary selector is set to OFF in order to de-energize the ADIRU. The OFF lights of the IR and ADR pushbutton will go off.
Setting the IR mode rotary selector to OFF is an irreversible action. Therefore, both PF and PNF must clearly identify the corresponding selector before setting it to OFF.
• If IR 1(2) affected:
In order to prevent possible failure of ADIRU 3, the flight crew must switch the AIR DATA and the ATT HDG in the following order:
-AIR DATA SWTG ………..………..……… CAPT (F/O) ON 3
-ATT HDG SWTG ..………….…………….. CAPT (F/O) ON 3
TO BE CONTINUED ON NEXT PAGE
CAUTION
RRRRR RRRR
• If one ADIRU already disconnected before failure:
In case of dispatch with one ADIRU under MMEL or one ADIRU already disconnected in flight, and an IR failure occurs, either detected by an IR 1+2 (1+3)(2+3) FAULT or with ATT red flag displayed on CAPT or F/O PFD, the affected IR and the corresponding ADR must be disconnected.
NAV IR 1+2(1+3)(2+3) FAULT, or ATT flag displayed on CAPT (F/O) PFD
-IR (affected) pb ………………..…….………… OFF
The affected IR is the one self-detected faulty or supplying the PFD displaying the ATT red Flag.
The OFF light may not illuminate
-ADR (corresponding) pb …………………….. OFF
ADR 1 corresponds to IR 1.
ADR 2 corresponds to IR 2.
ADR 3 corresponds to IR 3.
The OFF light may not illuminate
-IR (affected) MODE rotary selector ……….. OFF
The IR mode rotary selector is set to OFF in order to de-energize the ADIRU. The OFF lights of the IR and ADR pushbutton will go off.
Setting the IR mode rotary selector to OFF is an irreversible action. Therefore, both PF and PNF must clearly identify the corresponding selector before setting it to OFF.
CAUTION
• If IR 1+2 affected:
In order to prevent possible failure of ADIRU 3, the flight crew must switch the AIR DATA and the ATT HDG in the following order:
-AIR DATA SWTG ……….………………….CAPT ON 3
-ATT HDG SWTG …….……………..………CAPT ON 3
Note: First officer can recover IR information, by using the EFIS DMC selector (copy of the opposite side).
SPD BRK ………………………………….…….. DO NOT USE
• IF CG AFT 32%:
-T TANK MODE………………….……….. FWD
F/CTL ALTN LAW (PROT LOST)
MAX SPEED ………………………..………..…. 330/.82
OEB N° Page 4 of 5
74/4
OEB N° Page 5 of 5
74/4
OEB REMINDER:
On aircraft that have the OEB reminder function, the procedures of NAV IR 1(2)(3) and NAV IR 1+2(1+3)(2+3) FAULT ECAM cautions may be flagged.
The “refer to QRH PROC” line will then be displayed instead of the procedure itself.
To flag those procedures, the following codes should be entered in the FWC OEB database.
Code WARN STS
NAV IR 1 FAULT YES NO
34/10/050/061
NAV IR 2 FAULT YES NO
34/10/060/063
NAV IR 3 FAULT YES NO
34/10/070/065
NAV IR 1+2 FAULT YES NO
34/10/020/055
NAV IR 1+3 FAULT YES NO
34/10/030/057
NAV IR 2+3 FAULT YES NO
34/10/040/059
CORRECTIVE ACTION:
Under investigation
Note: The interchangeability code, given in the Illustrated Part Catalog (IPC), indicates the conditions for interchangeability of equipment. After installation of corrective modification(s)/SB(s), if an Operator reinstalls any equipment affected by this OEB it is the Operator’s responsibility to ensure that the recommendations given in this OEB are applied again for the applicable aircraft.

Edit:

Is it really a problem with the ADIRU equipment itself ?

[takata]

Then, wrong since the beginning...

augustusjeremy:
Yes, Aguadalte...
You were right since the beginning.
[...]
APPLICABLE TO:
All A330 aircraft fitted with NORTHROP GRUMMAN – LITTON ADIRU

I just wonder what in this case is convincing you to believe that an A330-200, fitted with HONEYWELL ADIRUs, and showing problems with unreliable airspeed probes freezing, would be comparable with an A330-300, fitted with NORTHROP GRUMMAN-LITTON ADIRUs, and showing AOAs spikes unfiltered?

What in AF447 ACARS sequence is similar to QF72 case?
- answer: nothing.
So, maybe its time to drop this claim for lack of any substantial or relevant fact to come with.

S~
Olivier

[augustusjeremy]

acars

What in AF447 ACARS sequence is similar to QF72 case?
- answer: nothing.
So, maybe its time to drop this claim for lack of any substantial or relevant fact to come with.

Takata,

I cannot answer this question because I don't have QF72 ACARS sequence.

What I know is that a single IR failure in QF72 (not two or three) made the A/P disconnect and so on, similarly to the AF447 case.

And a sudden pitch down might have made them decide to turn ADIRU1 off in association with the QF72 incident.

Nothing to Blame specifically. I just wanted to discuss a possibility and was a little provocative to get some feedback.

[Will Fraser]

augustusjeremy/takata/PJ2

AD 2008-0010R1 07/October/2008 EASA

Be careful what you turn off, lest nose drop.

[PJ2]

augustusjeremy;

The question is: Did they turn on ADIRU1 again ? Wouldn't it take some time to realign ? And how would it realign without trustful IR data (as the other two IRs were probably disagreeing ?)

[my bolding]

It should be clearly understood by anyone examining this course of action, that once the rotary switch is turned OFF, the IRS cannot be re-aligned without landing the aircraft. That fact has been understood since 1972 when INS first entered airline service.

The irreversibility of this action is noted in the OEB thus:

• If all ADIRU operative before failure:
If one IR is self detected faulty or if the ATT red flag is displayed on the Captain or First Officer PFD, the affected IR and the corresponding ADR must be disconnected.
NAV IR 1(2)(3) FAULT, or ATT flag displayed on CAPT (F/O) PFD
-IR (affected) pb …………………………..…… OFF
The affected IR is the one self-detected faulty or supplying the PFD displaying the ATT red Flag.
The OFF light may not illuminate
-ADR (corresponding) pb ………..…………… OFF
ADR 1 corresponds to IR 1.
ADR 2 corresponds to IR 2.
ADR 3 corresponds to IR 3.
The OFF light may not illuminate
-IR (affected) MODE rotary selector ……….. OFF
The IR mode rotary selector is set to OFF in order to de-energize the ADIRU. The OFF lights of the IR and ADR pushbutton will go off.
Setting the IR mode rotary selector to OFF is an irreversible action. Therefore, both PF and PNF must clearly identify the corresponding selector before setting it to OFF.
• If IR 1(2) affected:
In order to prevent possible failure of ADIRU 3, the flight crew must switch the AIR DATA and the ATT HDG in the following order:
-AIR DATA SWTG ………..………..……… CAPT (F/O) ON 3
-ATT HDG SWTG ..………….…………….. CAPT (F/O) ON 3

Once the rotary switch is turned OFF, all attitude information from that ADIRU is lost. Depending upon faults, one may lose all attitude information (as per the cautions expressed in the OEB) if one does not strictly follow this OEB.

Needless to say, one is extremely careful and deliberate in taking these actions. One does not execute these actions swiftly or without confirmation with the other crew member. One very obvious reason for caution is, the ADIRUs are not numbered sequentially from left to right, (1,2,3) but are instead numbered 1,3,2 - to represent the (schematic) correspondence of the ADIRU to the left (captain) and right (First Officer) systems and the #3 backup for either system depending upon the data switching. Among other reasons, when on IRS-ONLY or GPS Navigation, (beyond land) one never messes with the ADIRUs unless absolutely necessary.

Some will think and perhaps argue that the situation faced by the QANTAS crew, if faced by the AF447 crew (which is the case in fact being argued here), that swiftness is the order of the day due to rapidly unfolding/deteriorating circumstances. I submit that that is not the correct approach as mistakes can and will be made any emergency procedure is rushed. These are "mission-critical" systems the loss of which is a threat to the safety of the flight. At the same time, one does not dawdle but gets on with it directly - a well-trained crew that is familiar with both the system and the procedure can execute this swiftly and accurately. A crew that is hesitant because they do not know the system thoroughly may be at a disadvantage depending upon other circumstances. The QANTAS crew could not have been expected to comprehend what was going on with their aircraft.

I frankly doubt if this scenario unfolded but it is, as other scenarios are, a possibility.

takata;

What in AF447 ACARS sequence is similar to QF72 case?
- answer: nothing.
So, maybe its time to drop this claim for lack of any substantial or relevant fact to come with.

Precisely.

augustusjeremy;
I think you have the feedback you were seeking...

For orientation and understanding, the respective panels are shown below:



ADIRU control panel - Overhead Panel, top left



Switching Panel - forward Pedestal

[takata]

Be careful...

Will Fraser:
AD 2008-0010R1 07/October/2008 EASA
Be careful what you turn off, lest nose drop.

I'm not turning off anything until facts are making some leads very very unlikely. You are pointing an EASA AD concerning:
1. very specific models (without rev.), about which we don't know if F-GZCP belongs to any.
2. very specific in flight Law (re)configurations (low level go around), when FCPC1 is inop and FCPC3 not fully powered, with an engine stopped.
3. a transient pitch contol problem when pitch reset to zero.

On the other hand, (only if F-GZCP could initially develop such an issue):
a) she was at FL350;
b) she had both engine running;
c) she had AP, A/TRH, PFD off;
d) she was in Alternate Law 2;
e) she had an FCPC1 reset when a-d conditions were still valid.

Considering 1-3 vs a-e, it makes it very stretched to consider that what could have been a very serious issue at low level would precipit F-GZCP out of control from FL350 when almost none of these documented "upset" conditions were never met by her at any time.

Consequently, this "nose drop" theory is mostly an attempt to bend the facts in order to fit it, beside discarding all we know that doesn't fit very well, as plenty of "probe icing" experiences just proved that no aircraft ever had such a tendency to upset (and drop nose) in this case.

S~
Olivier

[Will Fraser]

takata

What I thought initially as well when the AD was forwarded to me.

Since it is a flight controls issue relative to the computer, and involved similarities with ACARS from 447, I'm not convinced it doesn't obtain.

See "PRIM1" specifically. Inop or selected off, the chain is interesting relative to HS movement and the possibility of overspeed leading to upset.
You are the authority here, along with PJ2. I defer.

I still await some info that proves the pitots iced. On any flight. The Thales R&R only mentions "improved" performance, not a "fix".

Will Fraser

[augustusjeremy]

auto flight, etc

e) she had an FCPC1 reset when a-d conditions were still valid.

Takata,

I beg to differ. I think this is at least controversial.

And I remeber you saying something about failed engines. Maybe that's why Will Fraser is coming up with that AD now.

PJ2,

I understand your point. I thought realignment could be done in flight if you had the other two IRs ok.

Of course if you don't have any NAV information to realign from you will have to land and do it on the ground anyway.

But remember that if a pitch down ever occurred - something equally controversial - the crew would be put in extreme stress - not understanding what really was going on.

Let's also recall that between 2:11 and 2:12 (2:13 ?) zulu that night something happened that caused a brief interruption in the ACARS message transmission.