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AF447

Old 11th Jun 2009, 16:46
  #1161 (permalink)  
 
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rudder/fin separation and satcom links...

Rudder Travel Lim. Fault in the Acars Messages and its link to rudder/fin/whatever loss would stand valid only if someone proved that the SatCom link would keep functional after the separation.

Either it must be plausible that the a/c wings could keep minimally horizontal and also minimally stable in that position with a missing rudder/fin/whatever or it must be proven that the satcom (electronically steered / phased array ?) link would stand even to abrupt changes in the a/c roll, pitch angle.
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Old 11th Jun 2009, 17:11
  #1162 (permalink)  
 
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come on lets back on the centre line. It might make a good bedtime story talking about losing VS etc. but its unfortunately bullshit.

The loss of a VS would produce many more faults than you have here, many more.

Once again acars is only a messaging system. It doesn't produce any messages it just sends them. The messages are aircraft system time stamped and not acars time stamped.

What we clearly see with these messages is the beginning of a sequence of tragic events tied to air data but still for reasons unknown.
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Old 11th Jun 2009, 17:16
  #1163 (permalink)  
 
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Config Full Re: AF908 CDG-TNR, captain PF report

I have made a very rough translation of the report using http://www.systran.co.uk/

I have only a very basic knowledge of the language (apologies in advance) and its intended intonations and nuances, so have kept the grammar amendments to a minimum to avoid the possibility of unintentionally mistranslating the proper intent of comments contained with the report. You might have to knock any mis-trans or rough edges off.

F-GNIH AF908 CDG - TNR -

STALL ALARMS AND LOSS OF THE SPEED INDICATIONS ON THE PFD

CDB PF in left seat and OPL L. xxxx PNF in right seat, OPL R. xxxx in rest

To FL 370 with a SAT with -51°C and a wind of the 080 per approximately 18Kts on AWY UB612 with OFFSET 1R, between points OBD and MLK in radio operator contact with KHARTOUM, as we were in limit of vapor cloud with some light turbulences, I had attaché the PAX.

We were in the twilight with a weak luminosity.

Then we entered the layer, and shortly after we started by having a light smell of burning which lasted about twenty seconds and which did not seem to be of volcanic origin (not rotted egg odor) but rather of electric odor for me and of odor air conditioning for the OPL. Then this odor disappeared. This odor was confirmed in cabin by the PAX and the PNC between the rows 3 and 14 thereafter.


We had the radar weather walks from there on gauged without apparent echoes always in the layer and approximately minute after this smell of burning, we had strong turbulences. I thus have make the message Here “attached cockpit PNC sitted strong turbulences”. I reduced speed to
Mach 0.80 (a little above green dot)

A few seconds after the indication speed on PFD OPL abruptly from 280 Kts passes to 100 Kts in the red stringcourse and that to lasted of many seconds. At the same time on PFD CDB very strong variation speed with speed indicated green dot less 15Kts and a speed trend to less 50 Kts.

At the same time (it was 15h10 TU) Alarm red A/P OFF then in the alarms amber ADR DISAGREE, IAS DISCREPANCY, ALTN LAW PROT LOST, REAC W/S DET FAULT.


Followed at 15h11 of alarm RUD TRV LIM FAULT with amber.


Follow-up immediately of alarm STALL STALL STALL (without associated alarm cricket) with indication of TOGA LK. As I always had the speed trend to less 50 Kts, I flew the plane manually with setting in descent and light turn to leave the AWY on the right. The plane answering very listlessly with on PFD CDB several regressions speed in the lower red stringcourse. At the same time I asked the OPL to send a message MAYDAY. During the descent rustles of impact (hail???) heard with the cockpit.


Descent until FL 340. Correct speed plane being become again I have slovenly the ATHR to leave TOGA LK. The indication speed being similar with dimensions CDB and OPL, but with bottom of the 2 PFD on the scale speeds the red indication SPD LIM which remained until the end of the vol.
Stabilization of the plane, then application of the IAS procedure DOUBTFUL, and started at the same time of anti icing ENG and WING like passage of PACKS FLOW on HIGH (in the doubt of a cloud of dust or smoke to avoid pumping GTR as in the procedure volcanic cloud). As the indications speed and altitude were correct (with cross-check with the indications of Ground speed and GPS altitude, thus when comparing the data of wind of the OCTAVE), ré engagement of the AP1 and the ATHR.


We did not have at any time of ICE DETECTION alarm.


I awoke the second OPL which was in rest, then we treated checklist ECAM.

Descent in FL 330 then chancel of the MAYDAY and continuation of the flight on this level.


The plane having passed in ALT LAW (MAX IAS 330Kts/M.82) I preferred to have a beach of flight envelope widened and continued the flight at Mach 0.80.


On the level of the assessment: plane in ALT LAW confirmed by the status and the crosses ambers on the PFD, REAC W/S DET FAULT, ALT LAW PROT LOST, ADR DISAGREE and F/CTL RUD TRV LIM FAULT (2
NOGO).
FOR LDG USES FLAP 3.


It is important to note that the indication on the circuit page of screen SD, of the RUDDER TRAVEL TO LIMIT was amber but with mid--chases between the neutral and full clearance rudder.


Contact with the CPC to know which was the state of the cabin and the PAX. Only strong turbulence was felt by the PAX.


I called by SAT COM maintenance to make a more thorough research of the problems and continuations to their recommendations we reseté all the calculators of orders flight PRIM and SEC without any result. (at this time there we had the fuel for a return towards NCE or FCO).


On the developed checklist of F/CTL ALTN LAW (PROT LOST) one can read for APPR PROC FOR LDG USES FLAP 3. (There is no indication in the QRH on the table of correction after breakdown)


On the other hand in developed F/CTL RUD TRV LIM FAULT in APPR PROC FOR LDG USES FLAP 2, which is confirmed by the QRH in the table of correction after breakdown.


As it appeared this anomaly between the QRH which requires to be poser volets 2 and the status which requires of us to be poser volets 3 it was thus necessary new searchs and thus the decision for a call later to QB.


New call SAT COM to QB which did not find an explanation additional on the difference in steering shutter, then with the CCO to see with them for the continuation of the flight and the breakdown service of the plane, the return towards Europe not being more possible with the remaining fuel, it was posed the decision then of to continue on TNR or to divert on RUN. Decision to continue on TNR with request for my share to postpone the alarm clock of the colleagues who were to bring back the plane on minimum CDG taking into account the 05hr00 of fault finding to TNR.


We continued the flight with Pitot heat in ON position and calibration radar on MAX.


It should be noted that during all the descent in ALT LAW, the plane did not answer my request for regression speed via order SPD of the FCU (we were into OPEN DES), and I have thus to disconnect the AP to make regress speed. The piloting of the plane gave the impression of a very soft plane to me to the orders, which did not correspond to not felt piloting during takeoff and the rise. Because of difference between the QRH and the status, I thus followed it status and we were posés volets 3.


While looking in ACMS we saw the indications of Pitot 1 & 2.2 & 3 and 1 & 3 fault at 15h10TU In post flight report
15h07 BMC 3
15h10 AUTO FLIGHT AP OFF
REAC W/S DET FAULT
IAS DISCREPANCY
NAV ADR DISAGREE
15h11 F/CTL RUD TRV LIM FAULT


I have make the turn of the plane with one of the OPL and as well the radome as the pitots seemed intact.


Only the angle of attack sensor with dimensions OPL was strongly tilted almost vertical. There was no trace of impact neither of stripe on the painting of the radome, nor on avoid-break.


I made, after having joined together all crew (PNT and PNC) a débriefing to explain what we had lived and to reassure everyone and answer the questions.


For the questions of the DM


Flight in FL 370 pas de shearing of wind felt (wind of the 080/18Kts) the wind was stable since more than one half hour in force and direction.


Flight at Mach 0.80 because light turbulence (attached PAX)


No audible presence of hail at the beginning of the incidents (but we heard during the descent of the noises of impacts to the cockpit (hail???).


Temperature SAT -51°C (we never had ICE DETECTION alarm)


No stormy phenomenon (nothing with the radar weather which on was gauged and no visible flash of storm).


Beginning of strong turbulence around 15h09 followed by alarms quoted above at 15h10 and 15h11TU


The indication speed side OPL passed from 280 Kts to 100 Kts in the red stringcourse and remained many seconds like that.


Coté CDB speed indicated passed from green dot - 15 Kts with a speed trend to -50 Kts.


Alarms STALL (without alarm cricket) several series with several incursions of speed indicated into the lower red stringcourse.


Stabilization plane with the FL340 then continuation of the flight in FL 330.

Duration estimated of incidents 3 to 5 minutes.
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Old 11th Jun 2009, 17:33
  #1164 (permalink)  
 
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sim scenarios..

one thing is for sure now..

the different reports, like Air Caraibe, and AF 908 and the speculation about a similar problem with the accident in question will lead to careful evaluation and new training scenarios in the SIMs..

question to the A330 / 340 drivers..

do the simulators employed presently faithfully duplicate handling at high alt in alt law?
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Old 11th Jun 2009, 17:33
  #1165 (permalink)  
 
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Have non-Airbuses ever had this pitot major icing problem ?

Or is it that Airbuses flight computers are much more sensitive to deviating pitot sensors due to icing ?

How is the B777 different and less sensitive to pitot icing and its flight computers are less sensitive to pitot icing ?
.
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Old 11th Jun 2009, 17:39
  #1166 (permalink)  
 
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Different pitot tube design. There's no indication the Airbus computers are any more sensitive to bad air data than the Boeing ones. One rule holds true for all computers: garbage in = garbage out.
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Old 11th Jun 2009, 17:41
  #1167 (permalink)  
 
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unreliable airspeed indications

I have read a lot about the possibillity that icing (or anything else) MAY have clogged the pitot-tubes, airlines changing the tubes etc etc.

But to measure airspeed (at altitude) you need static-pressure as well!
I have not seen any discussion on this, or does it work different on the -330? (i can´t imagine)
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Old 11th Jun 2009, 17:51
  #1168 (permalink)  
 
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No 25 - AIR FRANCE FLIGHT 447 SEARCH REPORT
PRESS RELEASE 25 (10/06/09, 19h00)
INFORMATION ON THE SEARCH FOR AIR FRANCE FLIGHT 447


The Brazilian Navy Command and Aeronautical Command inform that the Dock Landing Ship Rio de Janeiro , with a crew of 363 military personnel from the Brazilian Navy, should be joining the search and rescue operations from the 19th of June onwards. Having come from Haiti, the ship will pass near the city of Fortaleza (CE), where it will receive the reinforcement of two helicopters, a H-12 Esquilo and a H-14 Super Puma , both of the Brazilian Navy.

The French ship Mistral and the submarine Émeraude have already arrived at the search area and the seagoing tub Fairmount Expedition , contracted by the French government, has received permission to dock, today, at the port in Natal (RN), where it will receive American equipments (sensors and sonars), that will be used to search for the data recorder of the Flight AF 447 and the voice recorder of the cabin (commonly referred to as the "black boxes").

It should be emphasized that these vessels and equipments are at the service of the aeronautical authorities of France, by means of their aviation accident investigation body, the Bureau D’enquêtes et D’Analises pour la Securité de l’Aviation civile (BEA).

The work of these ships will be coordinated by SALVAERO and by SALVAMAR NE, that will monitor the position of these craft so that they do not interfere with the priority task, the search and rescue of bodies. It should be noted that, even though they are in missions of distinct nature, that these ships arriving today will contribute, whenever possible, with the rescue of bodies.

Besides these, two BEA investigators, one a structural engineer from Air Bus and the other a structural engineer from Air France , should be arriving in Recife (PE), on the 14th of June.

The Frigate Constituição , of the Brazilian Navy, is scheduled to arrive tomorrow, 11th of June, to the area where the search effort is concentrated. On the same date, the Frigate Bosísio should be arriving at a location close to Fernando de Noronha, where the 25 bodies on board will be collected by two FAB helicopters, a H-60 Blackhawk and a H-34 Super Puma , currently positioned in Fernando de Noronha.

Due to the meteorological conditions today, some of the search aircraft had their routes altered to areas with more favorable conditions for visual search. Sea conditions were satisfactory for the ships.

NAVAL SOCIAL COMMUNICATION CENTER
AERONAUTICAL SOCIAL COMMUNICATION CENTER
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Old 11th Jun 2009, 18:01
  #1169 (permalink)  
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Thanks to 'The Chaser' for the attempted translation of that report. Interseting to note the use of « Ici le poste de pilotage PNC assis attachés turbulences fortes » in the PA made. I still await someone from AF to confirm whether this is a 'known' description and to what grade it relates.It all sounds very similar, except unfortunately there is no-one to tell the tale.
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Old 11th Jun 2009, 18:07
  #1170 (permalink)  
 
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The Chaser - here is what translate.google.com gives. It's slightly more readable.

===8<---
F-GNIH AF908 CDG - TNR --
STALL ALARM INFORMATION AND LOSS OF SPEED ON THE PFD
CBD PF in the left seat and OPL L. xxxx SOPs in place right
OPL R. xxxx rest

At FL 370 with a SAT to -51 ° C and a wind from 080 to about 18 Kts on AWY UB612 with OFF SET 1R, between the OBD and MLK in radio contact with Khartoum, as we were at the edge of layer cloudy with some light turbulence, I tied PAX.

We were at dusk with low brightness.
Then we entered the layer, and soon after we started having a slight burning smell that lasted about twenty seconds and that did not appear to be of volcanic origin (no smell of rotten eggs), but rather electrical smell to me and smell the air conditioning for the OPL. Then the smell has disappeared. The odor was confirmed by the PAX booth and PNC between rows 3 and 14 thereafter.

We had the weather radar in motion on calibrated without echoes still apparent in the layer and some minutes after the burning smell, we had severe turbulence. So I do the message "Here the cockpit sitting PNC Attached turbulence. I reduced the speed at
Mach 0.80 (a little above green dot)
A few seconds after the indication of speed on the PFD passes abruptly OPL 280 Kts to 100 Kts in the red band and it lasted for many seconds. At the same time on the PFD variation CBD high speed with speed 15Kts green dot less speed and a trend to
50 Kts.
At the same time (it was 15:10 GMT) Red Alarm A / P OFF and then in the wake alarm amber ADR Disagree, IAS DISCREPANCY, ALTN LAW LOST PROT, W REAC / S FAULT DET.
15h11 monitoring of the alarm RUD TRV LIM amber FAULT.
Followed immediately by the alarm STALL STALL STALL (without the associated alarm cricket) with TOGA LK. As I always speed trend within 50 Kts, I steered the plane manually, with a call for light downhill and turn right to exit the AWY. The aircraft responding very weakly with the CBD several regressions PFD speed in the lower red stripe. At the same time I asked the OPL to send a MAYDAY. During the descent noise impact (hail?) Heard in the cockpit.
Descent to FL 340. Speed aircraft is returned to correct the sloppy I ATHR to exit the TOGA LK. The rate is similar side CBD and OPL, but down 2 on the PFD speed scale indication SPD LIM red remained until the end of the flight.
Stabilization of the plane, then applying the procedure DOUBTFUL IAS, while activation of anti icing and WING ENG as well as passing on HIGH FLOW PACKS (probably in a cloud of dust or smoke to prevent pumping as in the GTR procedure
volcanic cloud). As indications of speed and altitude were correct (with cross check with the indications of Ground speed and altitude GPS, so when comparing wind data from the OCTAVE), re-engagement of the AP1 and the ATHR.
At no time have we had ice detection alarm.
I woke up the second OPL was at rest, then we addressed the ECAM checklist.
Descent to FL 330 and then cancel the MAYDAY and continued flight at this level.
The aircraft fell in ALT LAW (MAX IAS 330Kts/M.82) I have a favorite beach area expanded flight and continued the flight at Mach 0.80.
At the balance sheet: ALT LAW aircraft confirmed by the status and amber cross on PFD, REAC W / FAULT DET S, ALT LAW PROT LOST, DISAGREEMENT ADR and F / CTL FAULT RUD TRV LIM (2
NOGO).
FOR USE LDG FLAP 3.
It is important to note that the indication on the circuit of the screen SD of RUDDER TRAVEL LIMITER was amber, but halfway between neutral and full deflection rudder.
Contact with the CCP for what was the state of the cabin and PAX. Only the strong turbulence was felt by PAX.
I called SAT COM maintenance to further research the issues and follow their recommendations we reset all the computers and commands flight PRIM
SEC without any result. (at that time we had the fuel for a return to NCE or FCO).
On the checklist developed for F / CTL ALTN LAW (PROT LOST) could be read to APPR PROC FOR USE LDG FLAP 3. (There is no indication in the QRH on the table of correction after failure)
For the developed against the F / CTL RUD TRV LIM in APPR PROC FAULT FOR USE LDG FLAP 2, which is confirmed by the QRH in the table of correction fail.
As it appeared that discrepancies between the QRH requesting arise part 2 and the status which requires us to ask strands 3 and it was therefore necessary to further research and therefore the decision of a later call to QB.
New call SAT COM QB who has not found any additional explanation on the difference in steering component, then the CCO to see them for the theft and troubleshooting of the aircraft, the return to Europe n 'as much as possible with the remaining fuel, the problem then the decision
TNR continue or divert to RUN. Decision to continue on TNR with a request for me to postpone the revival of colleagues who had to return the aircraft in view of CDG 05h00 minimum fault-finding to TNR.
We continued the flight with the pitot heat on and on radar calibration MAX.
It should be noted that throughout the down ALT LAW, the aircraft was not responding to my request regression speed via the control of the FCU SPD (we were in the Open), and I therefore disengage the AP for reducing speed. Piloting the plane gave me the impression of an airplane flying very soft, which was not the feeling of flying during takeoff and climb. Because of the difference between the QRH and status, so I followed the
status and we laid 3 strands.
Looking ACMS we saw indications of Pitot 1 & 2, 2 and 3 & 1 & 3 at fault in 15h10TU post flight report
15:07 BMC 3
15.10 AUTO OFF FLIGHT AP
REAC W / FAULT DET S
IAS DISCREPANCY
NAV ADR DISAGREEMENT
15h11 F / CTL RUD TRV LIM FAULT
I did a tour of the aircraft with one of the OPL and both the radome pitot that appeared intact.
Only the side impact sensor OPL was heavily tilted nearly vertical. There was no evidence of impact or scratches on the paint of the radome and on the windshields.
I did, after meeting all the crew (TFN / PNC) a debriefing to explain what we had lived and reassure everyone and answer questions.
In matters of the DM
Flight to FL 370 not experienced wind shear (wind 080/18Kts) wind was stable for more than a half hour in strength and direction.
Flight at mach 0.80 as slight turbulence (PAX Attached)
No audible presence of hail in the early incidents (but we have heard during the descent of noise impacts to the cockpit (hail ???).
SAT Temperature -51 ° C (we never had alarm ICE DETECTION)
No phenomenon storm (nothing in the weather radar was not calibrated and a flash of lightning visible).
Top of strong turbulence to 15h09 followed alarms above and 15h11 to 15h10 GMT
The rate rose later OPL 280 Kts to 100 Kts in the red band and remained in as many seconds.
CBD side the speed is increased from green dot - 15 Kts with a speed trend to -50 Kts.
STALL alarm (no alarm cricket) series with several incursions of speed shown in the lower red stripe.
Stabilization aircraft at FL340 and continued flight to FL 330.
Duration estimated 3 to 5 minutes.
===8<---

{^_^}
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Old 11th Jun 2009, 18:24
  #1171 (permalink)  
 
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You are correct Safety Concerns. ACARS is a 'messaging system' only. And yet you restrict your comment to data it provides. You can't have it both ways. You say essentially that ACARS is quite fallible, then you infer that because it doesn't report more, conjecture isn't based in 'evidence', which is it, then? Is it dependable? Does it preclude entertaining things it doesn't 'report', Or is it not telling us the whole (or even major) story because it is only a 'messaging system'?
What I am saying to be clear is that acars is just a relayer of information. The information will go out as and when available or as customer programmed. What it wont do is behave in an extremely selective manner to assist speculative theories just because the VS has been found.

It is simple really no magic. Had the VS caused this accident there would be 1001 more messages. Those messages arent there. All systems send their messages to a central point which then transmits them.

ACARS has nothing to do with anything except that it has assisted this investigation by doing its job and transmitting messages it had absolutely nothing to do with as far as collecting them or producing them is concerned.
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Old 11th Jun 2009, 18:26
  #1172 (permalink)  
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Will Fraser;

Re ACARS messages, indeed it is merely a messaging system and not a flight data analysis tool. We cannot imbue it with more even if it is all we have.

Much of this thread is taken up with "interpreting" ACARS and the tiny traces available; this is very unstable ground upon which to base any thinking whatsoever.

Most have accepted that the trace of the messages "IS" what happened. We do not know this.

Many, including myself, cautioned against such interpretation at the very start of this thread but those who don't know seem to have the least fear in treading in these deep and extremely complex waters. Your post expresses this quite well.

The reason for such caution is, among other reasons, the fact that the ACARS is a maintenance reporting and messaging system, not a flight data analysis tool. The granularity of the data is very high, (stating the obvious).

Also, the ACARS messages that many of spent hundreds of hours pouring over, is only a map of the incoming messages from the fault-reporting sections of the individual systems.

Each AF system component may possibly have it's own BIT (built in test) capability and, when such system is not functioning as designed, the BIT processes analyze, possibly attempt a fix and finally report the fault or failure through the AIMS, (Aircraft Information Management System). I say 'possibly have it's own BIT because the FIDS - Fault Isolation and Detection System also does this job and is installed on FMGC#1, but the AOM does not specify which internal and external failures it monitors/records).

All ACARS functions are heavily tailored to an individual airline's specifications, not Airbus's. We do not have a lot of information on AF's ACARS system design...

The inevitable conclusion and the reason why the sequence of ACARS messages may mislead in the kind of activities taking place here and elsewhere is, the ACARS sequence is a map of the incoming messages and NOT a map of the fault-failure sequence of individual systems, which, due to their internal designs and BIT processes, may not report faults/failures immediately.

The reasons for skepticism are significant. The foundation upon which any theories are posited, is at best, unstable. Hindsight bias is very active especially in the area of pitot and TAT discussions. I posted information a while back not to confirm theories but to make the complexity and uncertainty of the task ahead abundantly clear especially to those who have no experience or training in these areas. This is an extremely (and I mean extremely) complex aircraft which cannot be known deeply by any one individual, and we have mere traces instead of data and tiny slices of the much larger picture in the now-found wreckage of the vertical stabilizer.

One bare thread doesn't make the finished suit. We have small bits of bare threads dancing about and no possibility of summarizing - there is essentially nothing to summarize yet.

We simply do not know the reasons for system faults and structural failures. Further, we cannot even posit theories - such territory is "where angels fear."

We do not know, for example, if the reconfiguration to Alternate Law (1 or 2?) was because of a bank angle exceeding 45deg or because of the loss of ADIRU information, or....?

It is not the positing of theories which in and of itself is unproductive and possibly even harmful. It is the "independant life" such theories swiftly gain in a pressurized pyschological environment predisposed to "finding out" which can distract and blind otherwise knowledgable and intelligent perceptions or cues.
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Old 11th Jun 2009, 18:33
  #1173 (permalink)  
 
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Can I just confirm that the ONLY supporting evidence leading posters to discuss a VS mid air break up is the fact the French Navy found it in the water?

If this is so, surely this is speculation going way to far!
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Old 11th Jun 2009, 18:40
  #1174 (permalink)  
 
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JD-EE

All

I apologise if this has been answered elsewhere (although I have been watching carefully).

There is still a ‘hairs on the back of the neck’ flag in my minds eye that hopefully engineering/training etc might clear up.

For their (AF447) speed (and altitude), when all the ducks are in a row (all protections working), the maximum rudder deflection available is 4 degrees … right?

Let’s assume for argument that the ACARS messages being discussed (for AF447) are correct.

Not withstanding ‘the damper’, from the moment ATA 27.23 F/CTL RUD TRV LIM FAULT was in play (in concert with the other sys messages):-

Would the flight deck crew of AF447 have had 4 degrees (8 degrees in total) rudder deflection available under foot (as with all protections in operation), or would it have been 10 degrees (20 degrees in total or magnitude 2.5 greater) rudder deflection available under foot (protections degraded/lost) as has been noted from knowledgable posters on this issue?

The reason for the question I guess is self explanatory!
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Old 11th Jun 2009, 18:49
  #1175 (permalink)  
 
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The Chaser

That is out of my area of competence. I know electronics not flight control. So take the following with a HUGE dose of question. {o.o}

I have noted three possibilities in discussions.
1) It remains as it was until the slats are extended.
2) It opens up slightly until the slats are extended.
3) It opens up all the way.

I BELIEVE that option 3 has been discarded and either option 1 or option 2 is the case. So far I don't know that an A300-340 expert has said anything definitive.

I PRESUME that the pilots would be aware of this change from the alarms given and have experience with the ALT rules at least in the simulators. So it is somewhat premature to decide they over-controlled and lost the entire VS assembly rather violently even if other observations vaguely suggest the VS was lost at altitude. We just do not have enough hard data to even make crazy assumptions.
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Old 11th Jun 2009, 18:50
  #1176 (permalink)  
 
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JD-EE

here is what translate.google.com gives. It's slightly more readable
This has already been posted/deleted here.

Readable? Perhaps, but unreliable, e.g: google makes a nonsense of the reference to AoA vane (therefore, what else . . . ?)
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Old 11th Jun 2009, 19:00
  #1177 (permalink)  
 
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If one adjusted EPR's to Turbulence Penetration settings and maintained attitude manually using the standby ADI....how many reasons why that would not have worked. Can these things not be hand flown.....to that extent?
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Old 11th Jun 2009, 19:03
  #1178 (permalink)  
 
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ACARS may indeed be a "messaging system" and not a FDR as several astute posts have pointed out, but there also exists the possibility that very similar message sequences have been seen by AF (or other carriers) before on other flights that obviously did not crash. Maybe AF (or other carriers) has seen a similar ACARS message sequence several times previous to AF 447 and knows what flight conditions produced that sequence. If this type of ACARS message sequence or partial sequence has indeed been seen in the past, I would suspect that those crews will be further debriefed to see what else can be learned. The CVR/FDR may never be recovered in this instance. Analysis of the debris/wreckage that can be recovered along with analysis of what could produce those ACARS messages may be all that there is to solve this tragedy.
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Old 11th Jun 2009, 19:13
  #1179 (permalink)  
 
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Safety Concerns,
Had the VS caused this accident there would be 1001 more messages. Those messages arent there.
Arent you just doing what Will Fraser accused you of doing before?
Can you reconcile your claim with post #1180?
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Old 11th Jun 2009, 19:17
  #1180 (permalink)  
 
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Location: UK
Age: 65
Posts: 475
It would also help if people who only read books but have no hands on experience of the A330 would also post economically otherwise their usually respected posts may be discredited but also send people in the wrong direction.

Hopefully this extract from the a330 MM will make things even clearer.
The first extract is from the CMS chapter (Central Maintenance System)

(2)
Links between CMCs and System BITEs

Two operating modes characterize the CMS (BITE + CMC): the normal mode and the menu mode.
(a)
The normal mode

This mode is based on permanent real-time memorization of fault data.

The next is from the CMS chapter on fault reporting via acars



General rules for CMC and systems data transmission -

-
automatic transmission from the internal logics
The automatic transmission:
. of the warnings and faults in real time


yes some minor systems report faults only when asked. The systems reported as faulty on AF447 were reported in real time. Any other scenario would have ensured that acars sent other real time collected messages.

Therefore the time of transmission is irrelevant as the faults are time stamped in real time and sent in real time. If there are any communications issues the time stamp remains time when fault occured.
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