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AF447

Old 27th Jul 2009, 21:08
  #3961 (permalink)  
 
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Squawk Ident, I defer to your hearing the original.

For what its worth, here is the English-language text of what he said on the France24 site.

According to Lieutenant-Colonel Xavier Mulot, chief investigator for AF flight 447, "We're expecting a lot from this study because, thanks to the way the debris was broken and traces of burns, it'll eventually allow us to understand what happened."
Most speakers with English as their mother tongue would say that he described the recovered wreckage as having traces of burns.
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Old 27th Jul 2009, 21:26
  #3962 (permalink)  
 
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Squawk is right. Lieutenant-Colonel Xavier Mulot did not say that trace of burn were actually observed, he was merely exploring possibilities and... expecting a lot from this study. Another BEA technical expert was interviewed (on other TV channels) and much more cautious about this study given the available data. Jeff
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Old 27th Jul 2009, 21:36
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Any link available to the original footage?

I cannot make out at all how exactly Col. Mulot expressed himself in French in the video: the voiceover masked it entirely.

The accompanying transcript says:

According to Lieutenant-Colonel Xavier Mulot, chief investigator for AF flight 447, "We're expecting a lot from this study because, thanks to the way the debris was broken and traces of burns, it'll eventually allow us to understand what happened."
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Old 27th Jul 2009, 21:56
  #3964 (permalink)  
 
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ArthurBorges -

The link as originally posted by Hyperveloce is:-

Journaux télévisés en vidéo - France 2

mm43
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Old 27th Jul 2009, 22:04
  #3965 (permalink)  
 
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Eventuellement

I will try to translate as precisely as I can what this man said.
Eventually is a "false friend". In English or in French.


You may listen (while it is still possible) to the original broadcast here:
Journaux télévisés en vidéo - France 2

and go to +12'

"We are expecting a lot from this study because it will allow us to understand by the shape of the debris, by the cuts and possibly marks of burn what happened."

In this context "éventuellement " may be translated by "perhaps".

The France3 network also covered the same event on the same day and interviewed the very same person. And he said almost exactly the same thing:

Journaux télévisés en vidéo - France 3

and go to +15'45''
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Old 27th Jul 2009, 22:05
  #3966 (permalink)  
 
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Awaiting a French translation, I did hear the word from the official, brulure. 'Burns'. I have no context, obviously my French is lousy.

The airfoil surface featured in both videos looks most definitely like Elevator. Found floating (obviously) as was the VS with Rudder. Who can determine where each was recovered ?
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Old 27th Jul 2009, 23:35
  #3967 (permalink)  
 
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No Confirmation of Evidence of Fire

His statement to A2 was:

"We're expecting alot from the investigation because it will enable us to understand what happened from the shape of the debris, how debris was cut up, and any traces of burning.

As noted, Col. Mulot was interviewed by FR3 as well, where he mentions "éventuellement des brûlures" = "any burn marks (we might find)".

My reading of both statements is that the good colonel is NOT saying he's seen any evidence of fire but simply allowing fire as a reasonable-to-remote possibility.

As I understand it, a second shipload of wreckage has yet to arrive and I speculate the colonel has in mind early reports of orange fires on the surface of the water or at least is speaking from general experience of a/c accident investigation.


End of story.

(Note, for pedantry's sake, that I have rejuggled his word order.)

The only weird thing is that footage showed several hydraulic jacks: I didn't know they floated.

Last edited by ArthurBorges; 27th Jul 2009 at 23:55.
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Old 28th Jul 2009, 00:27
  #3968 (permalink)  
 
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The only weird thing is that footage showed several hydraulic jacks: I didn't know they floated.
Um, if they were really air cylinder actuators they might have floated, especially if they had been still attached to something like the rudder or the elevator that were recovered.

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Old 28th Jul 2009, 01:39
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the AF 908: weather radar, Pitots freezing & stall alarms

Another companion case, the AF 908 (FGNIH) between Paris and Antanarivo, very similar to the two Air Caraïbes events, and to the AF 447 seen through the ACARS, available at:
Eurocockpit - Archives

Quick translation:

FL370, on the AWY UB612 (OFFSET 1R), between the OBD and MLK waypoints, in contact with Khartoum, above the cloud layer, light turbulence, crepuscular lighting.

-at 15h10TU: Pitot 1 & 2, 2 & 3 et 1 & 3 FLT
AUTO FLIGHT AP OFF, REAC W/S DET FAULT, IAS DISCREPENCY , NAV ADR DISAGREE, ALTN LAW PROT LOST
it is noted that the turbulence strength had increased just before (at 15:09) this event when they entered the cloud layer, with a burnt smell in the cockpit, speed was reduced to Mach 0.80 (just above green dot), cabin crew warned, no ICE DETECTION alarm.
a few sec. later, the speed indication on the copilot PFD plunged from 280 Kts to 100 Kts in the red band during numerous sec. In the same time, on the CPT PFD, the airspeed rolled back 15 kts under the green dot (& displayed a speed trend of -50kts).
immediately followed by a Stall, Stall, Stall alarm... without the cricket sound, triggering a TOGA LK indication.
-at 15H11 : amber alarm F/CTL RUD TRV LIM FAULT
Since the speed trend was still of -50kts, the hand flying CPT initiated a slight descent and turn (to depart from the AWY route). A MAYDAY is issued by the copilot. The airspeed recovered at FL340, the A/THR was disengaged (to exit the TOGA LK state). The altitude being stabilized, the "unreliable airspeed" procedure was implemented. Anti ICE ENG & WING, PACKS FLOW set on HIGH and cross-checking between the airspeeds / altitude and the GPS ground speed / altitude + the winds data from OCTAVE. AP1 & A/THR reengaged. Descent at FL330 and MAYDAY cancelled. The crew joined the maintenance by satcom for a more throughout failure analysis and a PRIM/SEC reset was decided without results. An incoherence is found about the flap configuration between the QRH and the status (?).
Like in the other cases, the Pitot freezing & corrupted airspeeds event lasted between 3 and 5 mn. The crew set the weather radar on max sensibility for the rest of the flight (it was on CAL and did not detect anything suspect before the Pitot freezing).
Jeff
PS) -One of the differences between the AF 447 and all these cases with Pitot problems is the A/THR settings when the fault sequence began (engaged in the AF 447 case, off and N1 fixed for the turbulence penetration in the other cases). The visual clues: the Air Caraïbe case was in daylight, the AF 447 was a night flight (all in poor met conditions). I don't see any pilot refering the pre-stall buffeting indication in their in flight/post flight analyze of the stall alarm event in the safety reports.
The reasons why the Air Caraïbe crew is convinced that the stall aalrms are not justified are not explicitely stated in the report. Maybe it is linked to a question asked by a pilot to other pilots here.
-The speed trend on which the pilot based his decision about the stall alarm is completely artefactual/spurious: why this speed trend is still computed & displayed on the PFD during a corrupted airspeed event ? (Pitots FLR+ADR disagree). He probably also had in mind that they were just above the green dot just before the sudden sequence of FLRs.
-And in the same manner, why is the stall alarm still generated during a corrupted airspeed event ? Is it mandatory for the manufacturers that their planes have a functionnal stall/overspeed alarms in all circumstances ? (Airbus knows the risks and displays it on the ECAM "risks of undue stall warnings). An alarm plagued by false alarms is no more a valuable alarm, it is a danger. This danger can be further increased by the applicable procedures.
- we may have slightly different sequences of Pitot-static gradual failures, different timings for the different phases (before the fault isolation/detection by the automation, revertion to degraded modes, phase before the stall/overspeed alarms, after). Some will enable the crew to implement a part of the "unreliable airspeeds" proc. before the stall alarms may occur, other will not (AF 908). According to the sequence, the crew attention may be allocated differently on the failure analysis, procedures/check lists implementation, hand flight, cabin crew warning, etc...). I feel it would very useful to have a short-list of the indicators that may enable a crew to discriminate between a false and a justified stall alarms. How much time the cross-checking implemented by the AF 908 crew using OCTAVE can take ? Are there faster ways ? (when the fligh security is impacted). On the contrary, being able to know the "false friends" that you must avoid to rely on in such a case of unreliable airspeeds, seems equally interesting.

Last edited by Hyperveloce; 28th Jul 2009 at 14:44.
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Old 28th Jul 2009, 13:57
  #3970 (permalink)  
 
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Failure of stall warning with unreliable airspeeds

RE: Hyperveloce (#3969 p.199)
Is it mandatory for the manufacturers that their planes have a functionnal stall/overspeed alarms in all circumstances ?
Systems whose functioning is required by the applicable regulations are subject to a safety analysis during the certification process. (See for example FAR 25.1309). The general principle is that there must be an acceptable relation between the calculated probability that a certain failure occurs and the effect of that failure on the safe continuation of flight.
regards,
HN39

Last edited by HazelNuts39; 28th Jul 2009 at 14:15. Reason: Correction of typo
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Old 28th Jul 2009, 15:19
  #3971 (permalink)  
 
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Originally Posted by HazelNuts39 View Post
RE: Hyperveloce (#3969 p.199)
The general principle is that there must be an acceptable relation between the calculated probability that a certain failure occurs and the effect of that failure on the safe continuation of flight.
I see. But we have:
1) an intrument or a device (can be a Pitot-Static system, a plane)
2) a signal/indicator monitoring the performance of 1)
3) relevant procedures when 2) is activated
4) crew training/reactions to 2), given 3) and their observation of 1)
and it seems that all the 4 contribute to the flight safety ? If the regulations only specify the first 2, are they sufficient to ensure a probability on the safe continuation of flight ? (How is the "acceptable relation" between 1)-2) & 3)-4) & the overall flight safety impact defined or evaluated ?). Are there specifications about false alarms rates in normal/degraded modes ?
Jeff

Last edited by Hyperveloce; 28th Jul 2009 at 15:52.
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Old 28th Jul 2009, 16:21
  #3972 (permalink)  
 
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Originally Posted by Hyperveloce View Post
I see. But we have:
1) an intrument or a device (can be a Pitot-Static system, a plane)
2) a signal/indicator monitoring the performance of 1)
3) relevant procedures when 2) is activated
4) crew training/reactions to 2), given 3) and their observation of 1)
and it seems that all the 4 contribute to the flight safety ? If the regulations only specify the first 2, are they sufficient to ensure a probability on the safe continuation of flight ? (How is the "acceptable relation" between 1)-2) & 3)-4) & the overall flight safety impact defined or evaluated ?). Are there specifications about false alarms rates in normal/degraded modes ?
Jeff
The regulations go a bit further than just requiring failure rates to be commensurate with the hazard.

The failure rate of systems (including their warning systems0 is as noted previously, covered by 25.1309, and specifically 25.1309(b)(1)and(2).

The provision of appropriate procedures is required per 25.1585(a)(2)and (3) for abnormal and emergency cases.

That the procedures provide "continued safe flight and landing" for the various failure cases is determined in accordance with various handling requirements (for example) with various precedents and guidance material concerning, say, degraded handling acceptable for such cases.

I suspect that, certainly at initial cert, the basic probability of total loss of the air data system was already so low that compliance was achieved without worrying about the procedures, and any procedure provided was above and beyond the basic cert requirements.

To answer the question about false alarms, a false warning is in itself a system failure and would be assessed like any other for its consequences versus the probability.
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Old 28th Jul 2009, 16:37
  #3973 (permalink)  
 
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I suspect that, certainly at initial cert, the basic probability of total loss of the air data system was already so low that compliance was achieved without worrying about the procedures, and any procedure provided was above and beyond the basic cert requirements.
That suspicion is worth examining in more detail

If true, it puts the aircraft outside of its presumed airworthiness standards under continued airworthiness and suggests that a product change to a more reliable system or a major change to other mitigation means is needed to continue safe operations in that fleet.

I was under the impression (could be wrong that the original design did presume a higher level of all-air-data system failures and as such adequate mitigation was presumed at the flight deck level.

Let's take another look at this.

edited due to dyslexia

Last edited by lomapaseo; 28th Jul 2009 at 20:18.
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Old 28th Jul 2009, 21:30
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Seat map

Seats marked in orange on the seat map shown by the France2 coverage would be from what I could determine:

J/CL 2AJK 3K 4AK 7JK TTL 8
Y/CL 19F 20AJ 22D 24D 26BK 28BK || 29F 30D 31DF 32GK 33BJK 34AFGK 35BJ 36K 38DK 39F 40F 41D TTL 30
TTL 38
The last row in Y/CL is 42 (ABJK) on this aircraft/configuration.

Strangely the Gendarmerie considers that the registration number of the doomed aircraft was "FGZPC" i/o FGZCP. This mistake is repeated on all the covers visible in the TV report.
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Old 28th Jul 2009, 21:38
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Apologies if this has already been covered:

Le Figaro - France : Sonde Pitot : un nouvel incident chez Air France

Le Figaro is reporting a pitot failure incident on an Air France A320 (flight 1905) on July 13 this year. It was equipped with the new Thales BA pitots which are meant to be more reliable. Incident only lasted a minute or so.
SNPL pilots' union may ask for the new Thales pitots to be replaced by Goodrich versions.
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Old 28th Jul 2009, 22:13
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Of the 38 matches, these represent 6 of the 16 passengers in First, 11 of 61 passengers sitting over the wings between rows 7 and 28, and 21 in rows 29 back, predominately on the right side. With three crew members recovered, that leaves 9 or 10 passenger matches remaining. (The matches presume that every passenger was in his or her assigned seat.)
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Old 29th Jul 2009, 00:47
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Hyper, you do realize that diagram is a really good argument for the plane hitting mostly flat and pretty much shattering tossing bits and pieces all over the place, don't you?

If it broke up in the air and spewed people from where it broke you'd see a different distribution, I believe. The broken fuselage with px still belted in probably would not hit hard enough to crack it again like an egg shell. And there'd likely be more px from either near the crack (both sides) or from where it finally broke up if it did. A fairly even distribution would not likely happen.

Yes, there are more from from the rear than from the front. And over the wings is somewhat lightly represented. The px from the front and rear argue for a complete breakup on inpact as the BEA suggested with the wing area being partially protected by the mass of the wings themselves.

If the px in those seats suffered compressed spines then the issue of how the plane came apart is "close" to settled. It had to have experienced a REALLY violent stop from a rather fast vertical fall. If the px had "flail" injuries but few if any spinal compressions from at least one area of the plane then it may have broken up at altitude.

Alas, none of this tells is WHY it got there. It is more data to fold in with "found here on date and time such and such, water currents, and 02:10:34 position report" data to find out what happened. Why and how are very likely FDR and CVR related questions. (I suspect both are needed to pin down precise reasons and sequences of events. CVR is probably more help than FDR.)

JD-EE
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Old 29th Jul 2009, 06:19
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Some similarities?

This report suggests a short time similarity - except for the tragic outcome -with AF447:

Incident: Air France A320 enroute on Jul 13th 2009, unreliable airspeed for one minute

Referring to the last sentence in the report; does anybody know anything about the difference/s between Thales and Goodrich pitot sensors? And - are they of the same basic construction for A320 and A330?

/gfmb
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Old 29th Jul 2009, 07:43
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"Lefigaro.fr" is reporting a new incident with A320 FCO-CDG as AF1905
( F-GFKJ?). This aircraft was equipped with Thalès pitot -BA serie (new model).
Crew experienced a loss of speed indication for about one minute.

AF management gas confirmed the incident.


Le Figaro - France : Sonde Pitot*: un nouvel incident chez Air France


..."And the report of the crew accessible on the Sentinel software from the company states again "a brutal loss of the indications speed and then a disappearance of anemometric information”. In other words, the pilot had no more informations on the speed of the plane and had to change to manual mode"...
In the same article it is reported that The SNPL (Syndicat National des Pilotes de Ligne) might call for a replacement of the entire AF Airbus fleet with Goodrich tubes.
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Old 29th Jul 2009, 07:51
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Unhappy With thanks to AV Herald

An Air France Airbus A320-200, registration F-GFKJ performing flight AF1905 from Rome Fiumicino (Italy) to Paris Charles de Gaulle (France), was enroute when all airspeed information as well other air data related indications were lost in the cockpit, autopilot and autothrust systems dropped offline. The crew continued manually until the indications returned about one minute later. The flight continued without further incident and landed safely at the Charles de Gaulle Airport at 20:35 local (18:35Z).

Weather satellite images show a well developed frontal system overhead France at 18:00Z.

Air France said, the airplane was already equipped with the modified pitot tubes (Thales BA type instead of the standard AA type). The maintenance ACARS messages received by Air France are similiar to those, that were received from flight AF-447 on June 1st, that crashed into the Atlantic Ocean. An investigation is underway.

The NTSB is investigating two similiar incidents, see Incident: Northwest A333 over East China Sea on Jun 23rd 2009, unreliable airspeed and Incident: TAM A332 enroute on May 21st 2009, unreliable airspeed and altimeter.

French pilot unions are querying similiarities between the crash, these incidents and this new incident and state, that if similiarities do exist, the pitot sensors must be changed to the rival products of Goodrich rather than Thales.

Metars:
LFPG 131930Z 20009KT 170V270 CAVOK 21/15 Q1011 NOSIG
LFPG 131900Z 19009KT CAVOK 21/15 Q1011 NOSIG
LFPG 131830Z VRB09G20KT 9999 FEW040 BKN066 BKN100 22/15 Q1010 NOSIG
LFPG 131800Z 20009KT 9999 FEW040 BKN066 22/14 Q1010 NOSIG
LFPG 131730Z 19011KT 170V260 9999 FEW040 BKN066 22/14 Q1011 NOSIG
LFPG 131700Z 19011KT 9999 FEW040 BKN066 BKN100 23/14 Q1010 NOSIG
LFPG 131630Z 20013KT 9999 FEW040 BKN066 BKN100 23/14 Q1011 NOSIG
LFPG 131600Z 18012KT 9999 FEW040 BKN066 BKN083 23/14 Q1011 NOSIG
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