Roll surface damage?
 

CONF iture:



RR_NDB:




Looking at the aileron & spoiler traces:


If NOT in A/P control the outboard ailerons are centered (active zeroed) at speeds above 190Kts. (Active zero =1.4[/FONT]° up)[/COLOR]

(In A/P control or certain failure modes outboard. ailerons can be controlled up to 300Kts)

This transition is visible @ 02:10:05 at A/P drop off.

The trace shows also the outboard ailerons remain centered all the way down even when the CAS was well below 190Kts.

This could be another protection from the PRIMS (due to rejection of ADIRU's?)

The position is sensed by the LVDT inside the servo actuator and not the actual surface position.

There is no separate surface position RVDT like in the elevator and rudderdesign.

However the adjacent servo-actuator (while in dampening mode) is still monitored and since this one is driven by the aileron it reflects the actual surface position.

If there is any difference between the active and the dampening servo a fault message will be triggered. (And aileron faults were NOT present)

There were NO outboard aileron commands from PRIM and because there were also NO aileron fault messages present, we can conclude the surface was still attached.

However we CANNOT conclude nor exclude the outboard aileron surfaces were completely undamaged.

The inboard ailerons did receive commands, A/C did respond to these commands and failures were absent.

***

From the spoiler trace:

In ALT 2 spoiler (roll function) 2, 3 and 6 are inhibited.

The only glitch you will find in the FDR trace is after ~02:13:35.

Traces of spoiler 5 (cyan) & 6 (amber) shows peaks thereafter, this could be the moment the PRIM 1 and SEC 1 were switched off.

#5 is controlled by PRIM 1 and #6 is controlled by SEC 1.

If the peaks are caused by aerodynamic loads we can conclude the surface(partly?) was still connected to the servo. (Spoiler position is also derived from the servo-actuator LVDT).

Surfaces damage
 

Hi,

A33Zab,

Fine biz,

Kind rgds.

That question should be addressed by the BEA ... let's wait and see.
The SECs should have taken over, no ?

My only eagerness is to make sure the victim's families have access to all the data, not only part of them. There is no excuse for the Judge not to include them in the proceeding. We want to know what happened, everything, not only what the crew did wrong.

No. SECs don't take over valid PRIMs. In case of unreliable airspeed many protections remain as for a last valid speed.

But wild speculation does not bring families closer to truth, it only decreases signal to noise ratio. You want the data not a garbage. :ugh:

This was addressed by BEA in interim reports that both wreckage as well as FDR recording indicate no structural failure up to the impact. Plane was responding to stick deflections, and was symmetric aerodynamically (otherwise it would not fall flat, wings level at such extreme AoA). It was (for many) surprisingly stable (many planes would need to enter flat spin to fall wings level from fl370 down to the .

Wild and unfounded (and in fact contrafactual) speculations were plenty here. When BEA said that fracture analysis of found rudder indicates almost flat impact with little forward speed and small roll to the left many here dismissed it and continued to speculate about plane disintegrating mid air. Then "black boxes" were found and read and surprise - they perfectly agree with that early rudder analysis. Yet still some contrafactual speculations surface all the time :=

Hi,

Indeed .... :)
Google Traduction

Except for the RTLU, that is new information and it would be helpful if you could elaborate on that.

According to BEA's Interim Report #3 p.27 (English version): The recorded airspeeds remained above 30 kt until at least 02:11:45.

Perhaps it one should distinguish "invalid" from "erroneous". At least one airspeed value became erroneous at 02:10:04.6. The ECAM message NAV ADR DISAGREE was generated after 02:12:00, so until that time at least two of the three airspeed values must have been within tolerance of each other, erroneous or not, but still 'valid' until 02:11:45.

Can anyone explain why there is a SPD flag on the left PFD between 02:11:40 and 02:11:45? (p. 44 of I.R.#3 EN)

Could those have been two (incorrect, but consonant) speeds upon which PF based his "Overspeed"? Plugged Drains only? Hence the continued PULL?

For that matter, if reading high, wouldn't A/P have input NU, and for how long prior to loss of reliable speeds?

Don't mind me.

No, the speed from ADR2 that was not recorded would have been close to either ADR1 or ADR3 (when different) which were recorded. Note also that the right PFD was showing the speed from ADR3 between 02:10:40 and 02:12:17.

Since the CAPT pitot and the F/O pitot are mounted in exactly identical symmetrically opposite positions on the forward fuselage, while the STBY pitot position is below the CAPT's and therefore in a slightly different airflow, I would expect ADR2 closer to ADR1 than to ADR3.

@HN39:
 

My copy of (p. 44 I.R.#3 EN) shows speed flag @ 02:11:40 not @ 02:10:40.
Is my copy again outdated? or do you need to increase the font size a little bit:)

Minor correction, STBY is below Capt. probe, to be exact 60° below datumline (Z=0) while Capt and F/O are @42°.

A33Zab;

You are correct on both counts, thanks for pointing that out. I've edited my post to correct the errors.

@HN39:
 

No thx,

BTW, very good observation! I don't have an answer.
Airspeed acc. graph was still above 30Kts.

Confirmed by the CVR transcript pages @ 02:11:40:


But this is contradictionary with:

Quote:

---

The FD 1 and FD 2 become unavailable.
The angles of attack 1 and 2 become invalid (NCD status)

---

Which implies CAS 1 AND 2 are <60 kt.

Outboard ailerons did not move when they should have. If there is a logical explanation, and there could be one, I would like to hear about it ...

Exactly my point. Full data to the families. FDR especially.
Airbus has full access to the data, which makes sense, naturally the families should also, why not ? What's the problem ?

They should not have moved. The EFCS retains the configuration associated with the last known good speeds. When the ADR monitoring began, the flight control configuration was locked, including RTLU and ailerons.

The rest is pure politics and anyone can spin that as they please.

Also THS? Flap? RTLU froze the Rudder. Does the lock remain locked? Also, do spoilers remain inhibited, and for how long? If speeds return, are controls all available? Also, if ailerons inhibited, how did ROLL DIRECT retain so much authority, without the outers?

Thanks for info sir.

A drop of 30 kt in 1s of either the median or the mean IAS around 02:11:40 could again have triggered the monitoring of the airspeeds by the FMGEC and the EFCS. That would explain the loss of the FD's, but not that the AoA's became NCD.

@HN39:
 

The ADR monitoring of FMGEC is a continuous process and rather complicated...:8
simplified it needs at least 2 valid sources for the command side, OWN ADR and ADR 3, with OWN ADR as default.
But the monitoring side takes all 3 ADRs (if valid) in account.
Don't know the exact influence of F/O switching to ADR 3 on monitoring logic.

Anyway:
@02:10:40 CAS (#1) seems to be in same range as ISIS trace (~ADR3).

02:11:40 CAS measurements are still above 60kt but not 5 sec later.

RTLU was initially stuck then non available, but what is your reference for the ailerons ?
Please quote ...

Clearly, many here are conversant with the 330's systems, and its pilotage. I certainly am not. So I am curious as to some things.

When the ADR's begin to be interrogated by the computers, as to reliability, isn't this ongoing? Or is this 'suspicion' the result of already sensed anomaly? Because if it involves locking of control limits (certainly not locking controls, that would be crazy), are the pilots on board with the 'suspicion'?

Most certainly, right? Wouldn't the flight crew be apprised instantly if A/S was thought sour?

As in: "Monsieur, the computer is interrogating our displays, heads up..."

Would that be the cue to start UAS protocol? Certainly. So Bonin was informed at the outset of the 'beginning' of UAS? At least its possibility?

Now, since H. Spinkleman has stated the controls' limits are locked at the beginning of such interrogation, may we assume the THS stopped trimming shortly after? It is shown, FDR, the THS remains at 3.5 degrees until just at apogee? Bonin knew this of course, he was without trim to PITCH.

Another has said, essentially, that all control surfaces were acounted for until late in the game. I differ, here. Since the ailerons reporting is accomplished by its actuator, the aileron 'need not be present' to be accounted for? Similarly, an elevator is in the same situation? Is there a tickle conductor to the Trailing edge, so, if its continuity is interrupted by surface separation, it is known in the cockpit/ACARS? I have not heard of one.

The "Aircraft handled in predicted response per the FDR". That's nice, but it does not account for all controls' surfaces to the strictest extent. The recovered spoiler separated at its attach to its actuator; the recovered elevator, at its hinge line. It is acknowledged that to entertain control surface separation may be difficult, even fearful, but thus far, we have BEA saying that the a/c impacted "......complete". They did not say "Completely intact, whole".

Lyman, I know lawyers speak the way you speak all the time, but would you mind writing in simple un-convoluted English for a change. It might help present your points more clearly. Choose simple words instead of the $5.00 words please.

Swear to God Mach, are you kidding? 5.00 words? Show me one, give me some direction. I'd be happy to edit.

sub Mach

Are the pilots 'told' instantly when the computer doubts the Speeds?

Did "control limit locking" involve THS?

Are surfaces linked to the computer, or just the actuator?

etc.?

I'm referring to the "10 seconds" speed monitoring process described on page 55 of BEA's Interim Report no.1 and again on page 40 of I.R.#3. It is triggered by a decrease of more than 30 kt in one second of the “polled” speed value. The polled speed value is the "median" or middle value of three valid ADR's or, if one ADR has been rejected, the mean of the two remaining values.

HN39

A decrese of 30knots/sec? Only? Not to include an increase of the same value?

Will someone say if the flying pilots are made aware of the urgency of the monitoring process post 30knot/sec. sensed? Are they "in the loop"? Or do they have to wait for the 'generic' cavalry charge and "MASTER CAUTION" without elucidation from the panel? My sinking feeling is that they are not made aware, that they have to await, in ignorance, the 'decision" of the Computer. No "Speeds" notation (verbal) exists until eleven seconds after a/p LOSS.

Did the AutoPilot quit at start of monitoring, and, ten seconds after its loss, the pilots were 'told'? Sounds impossible.

@CONF iture:
 

RTLU was not stuck, as in jammed, it was freezed at the position it was.
this is a protection not a malfunction of the RTLU.
RTLU reset would have been accomplished upon S/F selection.

If anyone can find the reference for the OB ailerons he is most welcome, I couldn't find it in words, but its there in the traces and since the roll function of spoiler 2,3 & 6 in ALT2 are inhibited to decrease the roll rate it is obvious to zero the OB ailerons for the same reason.

I ask again. The ailerons and spoilers inhibit remain in ALT 2? Where does she get her reputation for "twitchy"? And wouldn't this be counterintuitive, since Roll would then demand maximum from surfaces that were not intended to produce rapid Roll Rate?

Or are they limited to prevent excess YAW, the remaining Roll controls being closer to the longitudinal axis?

Open data
 

The BEA report is PUBLIC. Their report is said "administrative".

It is independant from the trial who does his own enquery (yes !) They have their own experts...

We have access only to the BEA enquery results.

The family may ask to the Judge the result of the Justice enquiry two.

The reality is very different : it is totally impossible for the Justice to do an independant inquery. But you have two groups of experts (all are generaly friends or colleagues one of another)...

That is in France ...

I used 'stuck' as it is the word they used for the translation on page 40 of the third Interim Report, but am I missing something here :
As the role of the RTLU is to limit rudder and pedal deflection as a function of the speed, and the position of the rudder limiter was stuck, frozen since 02:10:06, why that limit was exceeded when the rudder was suddenly and generously applied after 02:13:00 ?

I have not heard about the slats being extended earlier ...
S/F selection and position is just another trace I'd like to see.

"As the role of the RTLU is to limit rudder and pedal deflection as a function of the speed, and the position of the rudder limiter was stuck, frozen since 02:10:06, why that limit was exceeded when the rudder was suddenly and generously applied after 02:13:00 ?"

CONFiture. You will need to address the limit strength of the RUDDER actuator v. air loads. Just as the limit strength of the THS jackscrew is compared to the airloads on the THS. When takata posted the picture of the recovered jackscrew, I noted some damage at (near) the end (NU) limit of the screw. The rotation and torsional impetus of the jackscrew would be in opposition to the extreme airloading on the THS. If it failed, and trapped the collet in its near max. position of 13.2, that explains the nesting of the THS from apogee. Logic demands some movement post apogee with ND from PF. None is in evidence.

These questions are unaddressed here, and to my knowledge, not broached in the BEA reportage.

Best regards

Post apogee the Elevator was mostly at 30° NU and never came below 15° NU - short term. Why would the THS need to follow?

@CONF iture:
 

Because the RTLU is not a Rudder DEFLECTION Limiter but a rudder INPUT limiter.

@~02:13:00 the pedal input was abrupt and full 8° while Yaw damper was deflecting the rudder in same direction max 4°.

So a little overshoot occured (and torsion on the inputshaft) because yaw damper was unable to compensate in time.

http://i474.photobucket.com/albums/r...30_MRudder.jpg

Because they were not...

For lieman:

The LL (limit loads) are max loads expected in the normal flight envelope, the UL (Ultimate Loads) are 1.5 LL.
No breaking of the surface occurs before UL.

Hi mm43

I am reading Glyndwr with jaw dropped to floor. yes?

For A33Zab
 

A question:
Is this an add-on made after the AA587 crash? You know, where the pilot got blamed for "excessive rudder input"? (tail broke off) :*

@OF:
 

No, RTLU is common on A320 series, (PTLU) was added to this system on A34/33 from the start....AFAK.
My ATA 27 pages with diagrams of RTLU and PTLU are dated APR 1993.

But AA587 was A300 isn't it?

@A33Zab:
Thank you.
Yes.

I feel a bit uneasy by this statement, I must say.

The RTLU set the position of the rudder limiter (physical limitation). In this case it was between 5 and 6 degrees according to the graph on page 112 of the third Interim Report, but 8 degrees after physical observation as stated in the second Interim Report ... why such difference btw ?

The RTLU ECAM MSG then indicates the unavailability for further rudder deflection limitation calculation function, but the position of the rudder limiter was already frozen.

Nevertheless, at 02:13:00 the rudder reached 10 degrees ... not 'a little overshoot'

Could it be the consequence of the limitation value being unfrozen following a slats extension command ... ?
It is clearly mentioned in the second Interim Report that the flaps were retracted but I have not seen a word on the slats ...

Extending the slats could be an attempt to regain control, kicking the rudder like it was done at 02:13:00 could be another one ...

roulishollandais,
The families are 'parties civiles' and should have full access to the data.

Protections
 

I am studying carefully before posting part B and C on "Transient in feedback Systems II" and i have a question "hovering" in my mind. :8

Why not to implement a protection against climbing above REC MAX?


Protections are designed to "protect". It is reasonable to allow a plane climb (at high ROC) towards a FL above this important limit?

Hi,

CONF iture
Indeed .. as plaintiffs families are entitled to access to investigative files
But it's more complicated than that because the judge handling the case has not joined the FDR and CVR transcripts as exhibits to the investigation and therefore .. given the needs of the technical investigation .. BEA has given datas to Airbus and AF .. but not to families since they are not parts of the technical investigation .....
AFAIK
Dura Lex Sed Lex

@CONF:
 

IMO the TLU trace shows its RVDT angle ISO max. rudder deflection.

Ref. mm43: RTLU GRAPH

Ref. PJ2: R/PTLU

When the RTLU is at minimal (0° RVDT angle) the RTLU limits the rudder input to 4°, to be accurate this is 3.7° (CMM).
Interpolating the low resolution TLU trace its value was ~4.2° (RVDT angle) just before @02:10:05.
4.2° + 3.7° ~ 7.9° at which it was freezed by PRIM at the start of the speed monitoring process.

The following is purely speculative since I am not able to prove with documentation.

The PRIM freezed the RTLU at the start of the monitoring process, but it can not control it because the TLU electrical motors are driven by the SECs.
The PTLU and RTLU share the control relays but have separate driver circuits inside the SECs. (so far true)

If the SECs continue to drive the PTLU to 5.8° RVDT angle the limiting position of the PTLU will be 5.8°(RVDT angle) + 3.7° ~ 9.5°.
at that position it detected the RTLU is not following its command position and triggers the TLU NOT AVAIL signal and F/CTL RUD TRV LIM FAULLT @ 02:10:18.

The surface xdcr is placed at the lower side of the rudder, the lower servo is attached to the linkage before the RTLU, the upper and center input linkage after TLU.

As mentioned by A33Zab, the RTLU graphic he linked to is actually for the A333 (taller Vertical Stabilizer) and the graphic below is for the A332.

http://oi56.tinypic.com/ivvayo.jpg

No, why should it ?
The rudder pedal position was 10 degrees off max, so was the rudder (page 112)

FLAPS 1 selection on ground before take-off does provides both slats and flaps. It is called CONF 1+F
But FLAPS 1 selection in the air for landing preparation provides only slats. It is called CONF 1

Many data are missing ...
The BEA has provided too little.
What the Judge is waiting for ?
Who are those lawyers who pretend to defend the families ... ?