TAM A320 crash at Congonhas, Brazil
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This was published on August 15th:
[quote]
Iano Andrade/CB
No depoimento à CPI, Marco Aurélio Castro afirmou que vai equipar toda a frota com programa da airbus
Since the end of last year Airbus offered to the airlines the software FW3 that warns the pilots if the TLs, that control the potency of the turbines, are in the wrong position. Only after the accident that killed 199 people on 7/17 that TAM decided to buy the program by U$5000.00, R$10.000.00.
It is a modern software. For older planes it is necessary an adaptation. We are going to install in all planes. said Frota. He recognized that the equipment was available before the accident. According to TAM the instruction from Airbus classify the equipment as desirable but not mandatory. TAM decided to buy the equipment to reforce flight security.
[quote]
Iano Andrade/CB
No depoimento à CPI, Marco Aurélio Castro afirmou que vai equipar toda a frota com programa da airbus
Desde o final do ano passado, a Airbus ofereceu às empresas de aviação o software FW3, que alerta o piloto se os manetes, alavancas que controlam a potência das turbinas, estão na posição errada. Somente após o acidente que matou 199 pessoas no último dia 17 é que a TAM decidiu adquirir o programa, ao custo de US$ 5 mil, cerca de R$ 10 mil.
“É um software moderno. Para aviões antigos é necessário uma adaptação. Vamos equipar toda frota”, afirmou Castro. Ele reconheceu que o equipamento já estava disponível antes do acidente. Segundo a assessoria da TAM, instrução da Airbus classifica o software como um equipamento desejável e não obrigatório. A TAM decidiu adquirir o software para reforçar a segurança de vôo.
“É um software moderno. Para aviões antigos é necessário uma adaptação. Vamos equipar toda frota”, afirmou Castro. Ele reconheceu que o equipamento já estava disponível antes do acidente. Segundo a assessoria da TAM, instrução da Airbus classifica o software como um equipamento desejável e não obrigatório. A TAM decidiu adquirir o software para reforçar a segurança de vôo.
It is a modern software. For older planes it is necessary an adaptation. We are going to install in all planes. said Frota. He recognized that the equipment was available before the accident. According to TAM the instruction from Airbus classify the equipment as desirable but not mandatory. TAM decided to buy the equipment to reforce flight security.
Last edited by marciovp; 27th Sep 2007 at 22:31. Reason: To complete
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Thanks Rob21, PBL, marciovp, lots of excellent information.
There's actually some scope for optimism now that accidents of this type may be avoided in the future.
It's almost inevitable in cases of this kind that very little is usually said or done about remedial measures early on; that's usually inevitable, since any such action can and will be interpreted by the public (and later, perhaps, the courts) as an admission of liability.
It's therefore to the credit of the three parties that are most likely to share any blame - Airbus, the airline, and the airport authority (again in no particular order, it looks more and more like a straight 33.3% split on present evidence) - that they have ALL taken prompt action.
Airbus has offered the new warning system, the airline is installing it, and the airport authority has reviewed weight limits and is planning run-off areas. And a pretty comprehensive AOT has been circulated, so one can bet that the lessons learned from Congonhas are already being applied all round the world.
So fingers crossed that this particular type of incident/accident already looks a lot less likely to recur.
There's actually some scope for optimism now that accidents of this type may be avoided in the future.
It's almost inevitable in cases of this kind that very little is usually said or done about remedial measures early on; that's usually inevitable, since any such action can and will be interpreted by the public (and later, perhaps, the courts) as an admission of liability.
It's therefore to the credit of the three parties that are most likely to share any blame - Airbus, the airline, and the airport authority (again in no particular order, it looks more and more like a straight 33.3% split on present evidence) - that they have ALL taken prompt action.
Airbus has offered the new warning system, the airline is installing it, and the airport authority has reviewed weight limits and is planning run-off areas. And a pretty comprehensive AOT has been circulated, so one can bet that the lessons learned from Congonhas are already being applied all round the world.
So fingers crossed that this particular type of incident/accident already looks a lot less likely to recur.
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Three days ago (post #2397), I wrote :
Seeing the reactions here, I really did not expect to be right so soon !
Now the warning.
I am not really keen on the addition of another warning, especially one that tries to save a situation that is already complex in terms of crew failure interpretation. The AI proposal would only appease the political branch of the society and the uninformed public.
I am not really keen on the addition of another warning, especially one that tries to save a situation that is already complex in terms of crew failure interpretation. The AI proposal would only appease the political branch of the society and the uninformed public.
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Originally Posted by DozyWannabe
In all likelihood either the stenographer or a reporter misinterpreted the actual code of "FWC Standard H2F3" as "FW3". Easily enough done I guess.
Aurelio Castro will have to reconcile the statement quoted above by marciovp that this SW had been available since end of 2006 with his statement before the CIP on 14 August at which he said that the "system" which he called "FW3" had not been offered to them until that date.
My take is as follows.
AI has five reasons consistent with what M. Malinge said before the CIP not to have offered the SW before.
The two main reasons offered were:
(1) The task was to consider a warning system which would remind the pilots to reduce thrust to idle on flare. But this is not necessary: there is one already.
(2) Reducing thrust to idle on flare is a basic task of basic airmanship that every pilot learns from his first flight. Introducing warnings concerning items of basic airmanship is not good practice.
The subsidiary comments were:
(3) One must ensure that a new warning will be efficacious in its effect. AI could not determine that, when a crew have already ignored one reminder to reduce thrust to idle, they would pay proper attention to a second reminder.
(4) One must consider the effect of introducing new warnings on the entire warning situation, to avoid such issues as cognitive overload (aka the "Christmas tree" effect), which serves to distract a pilot from the actual necessary task. In particular, one must be very wary of duplicating warnings.
The fifth reason would be:
(5) Nobody understands why professional pilots would not reduce thrust to idle on flare/touchdown. Until someone understands why and how this can happen, or until it can be shown to happen repeatedly or more frequently than one supposes, reasons (1), (3) and (4) above mitigate against introducing supplementary warnings.
AI's position on (5) will be that, until the Congonhas accident, there was little evidence that failing to reduce thrust to idle on flare was an oft-repeated error. There were two incidents on record in (what AI claimed in its deposition) over 30 million fleet landings in 19 years.
AI may well have surveyed or will survey their operators who run a FOQA program and keep records and maybe find some more instances which have not resulted in anything noted at the time. They will then argue that A320-31-1267 Rev 3 was offered (a) in response to a customer request (that would be TAM on, let me guess, 10 August 2007); and (b) in response to a specific survey after the TAM accident which showed that the phenomenon of not reducing thrust levers to idle on flare occurred more often than previously thought (if this should indeed be the case; that is, more often than twice in 30 million landings), mostly without incident.
I think that would be a good rationale. It coheres with a lot of what has been said here, for example the incomprehensibility of the pilots' actions in not reducing #2 to idle on flare, and the inadvisability of having duplicate warnings for the same phenomenon, as well as the efficacy of a second warning when a first has not succeeded.
Where it might be weak in a court case is if strict liability prevails in Brazilian torts. I offer the following comments
under the understanding that I am not a legal eagle and might be deficient in my understanding of some general legal principles. I am certainly ignorant of Brazilian law on these matters. Strict liability is a legal concept whereby a manufacturer is held liable simply *if something happens*, and not only if there has been a breach of due diligence or duty of care, which are usually criteria for liability to be established in general civil cases. Most of the 5 points above would serve to establish that AI has discharged its duty of care. They do not serve to establish that its airplane didn't crash for a third time due to phenomena which have occurred before, and that might matter more under strict liability.
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RWA,
Very well put, it is good to see some optimism around here.
To all pilots here, specially the "older" ones,
There was a time when regs were not so strict and we (not crew) could go in to the cockpit and even seat on the jump-seat. On one of these cockpit "incursions", I remember very well seeing the Captain operating the TLs, with the assistance of the Flight Engineer (B-727), who had his hands on top of the Captain's right hand (TO and Landing). Later, on another of these "cockpit visits" (yes, I had 2 very close family members there...), the airplane was one of the first B-737 to arrive in Brazil and the Flight Engineer was not necessary anymore. But I saw the Copilot with his left hand on top the Captain's right hand (TO and landing). I believe this was a procedure, not a "friendly" gesture...
Years went by, I don't visit cockpits anymore. But watching a video of a landing, taken from inside the cockpit, I didn't see the copilot assisting the pilot with his hands. I searched for more videos, and could not see this "procedure" (TLs with two hands).
Now I wonder. If the "drill" on landing with one reverse inop included this "hand over hand" thing (very low cost, easy to train)...
Sorry if I "deviated" a bit from the subject. Just wondering...
Regards,
Rob
Very well put, it is good to see some optimism around here.
To all pilots here, specially the "older" ones,
There was a time when regs were not so strict and we (not crew) could go in to the cockpit and even seat on the jump-seat. On one of these cockpit "incursions", I remember very well seeing the Captain operating the TLs, with the assistance of the Flight Engineer (B-727), who had his hands on top of the Captain's right hand (TO and Landing). Later, on another of these "cockpit visits" (yes, I had 2 very close family members there...), the airplane was one of the first B-737 to arrive in Brazil and the Flight Engineer was not necessary anymore. But I saw the Copilot with his left hand on top the Captain's right hand (TO and landing). I believe this was a procedure, not a "friendly" gesture...
Years went by, I don't visit cockpits anymore. But watching a video of a landing, taken from inside the cockpit, I didn't see the copilot assisting the pilot with his hands. I searched for more videos, and could not see this "procedure" (TLs with two hands).
Now I wonder. If the "drill" on landing with one reverse inop included this "hand over hand" thing (very low cost, easy to train)...
Sorry if I "deviated" a bit from the subject. Just wondering...
Regards,
Rob
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Question...
There were two incidents on record in (what AI claimed in its deposition) over 30 million fleet landings in 19 years
Also I like you to pursue this notion that Airbus did not have the softare upgrade with bells and whistles according to what was recommended after Taipei. And that TAM asked for it. I did not see evidences for that in any of the depositions at the CPI of the House.
BTW, CENIPA just came out with a final report om the Boeing X Legacy Disaster. I would love to have a thread here to discuss this report. What do you all feel?
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Originally Posted by PBL
1) The task was to consider a warning system which would remind the pilots to reduce thrust to idle on flare. But this is not necessary: there is one already.
From the CVRs, the Taipei pilots thought that they had a brake problem; the Congonhas ones thought they had a spoiler malfunction. Had either crew known the true cause, even after touchdown, they could have retarded the offending lever straight away (or cut the engine if the cause was, for example, a jammed lever).
As the Taiwanese investigators pointed out, the present 'Retard' call cuts out after touchdown, whether or not both levers have been retarded. That is clearly an inadequate arrangement, if not an actively-misleading one (given that after the present warning cuts out, the pilots will arguably, on the face of it, be even LESS likely to suspect a wrongly-positioned lever?).
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Rob21.
Still happens in many places in the world, you know ?
Brazil is a very curious place, then. I only remember, on DC-4s the FE setting the *ordered* pressure from the pilot and the same procedure on the older 707s. On 747s, the flight engineer had, behind the throttles, appendages to allow him to set takeoff thrust and to keep the engines synchronised during the approach, set-up that was kept, among other planes on the 1011. With the avent of two-man-crew cockpits, the tasks were a lot stricter in terms of distribution and the *hand-over-hand* technique deemed too dangerous : One flies the airplane, the other monitors...Simple.
Maybe specialists have come to their senses, at last.
The answer is NO
You really have no idea on what happens in training, in system integration, in procedures design and implementation. So stop trying to tell us, even the *older ones* what was ,what is and what should be. Or stop flying altogether.
In the mean time, be happy : TAM will have a new bell-and-whistle gismo in their flight deck. Just what you wanted.
Now leave the *specialists* to try and work on this quietly.
There was a time when regs were not so strict and we (not crew) could go in to the cockpit and even seat on the jump-seat.
Captain operating the TLs, with the assistance of the Flight Engineer (B-727), who had his hands on top of the Captain's right hand (TO and Landing). Later, on another of these "cockpit visits" (yes, I had 2 very close family members there...), the airplane was one of the first B-737 to arrive in Brazil and the Flight Engineer was not necessary anymore. But I saw the Copilot with his left hand on top the Captain's right hand (TO and landing). I believe this was a procedure, not a "friendly" gesture...
Years went by, I don't visit cockpits anymore. But watching a video of a landing, taken from inside the cockpit, I didn't see the copilot assisting the pilot with his hands. I searched for more videos, and could not see this "procedure"
Now I wonder. If the "drill" on landing with one reverse inop included this "hand over hand" thing (very low cost, easy to train)...
You really have no idea on what happens in training, in system integration, in procedures design and implementation. So stop trying to tell us, even the *older ones* what was ,what is and what should be. Or stop flying altogether.
In the mean time, be happy : TAM will have a new bell-and-whistle gismo in their flight deck. Just what you wanted.
Now leave the *specialists* to try and work on this quietly.
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Same thinking
As the Taiwanese investigators pointed out, the present 'Retard' call cuts out after touchdown, whether or not both levers have been retarded. That is clearly an inadequate arrangement, if not an actively-misleading one (given that after the present warning cuts out, the pilots will arguably, on the face of it, be even LESS likely to suspect a wrongly-positioned lever?).
PS. Brazil will be in the final of women´s soccer, against Germany...
I will be away until 10/18... Perhaps someone can start a thread on the CENIPA´s final report on the GOL X Legacy.
Last edited by marciovp; 28th Sep 2007 at 15:01. Reason: typo
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Originally Posted by PBL
There were two incidents on record in (what AI claimed in its deposition) over 30 million fleet landings in 19 years
Originally Posted by marciovp
Shouldn´t this be measured differently? How many incidents (I believe it was three) in how many landings with one reverser locked?... This would be a better measure, no?
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Originally Posted by PBL
1) The task was to consider a warning system which would remind the pilots to reduce thrust to idle on flare. But this is not necessary: there is one already.
Originally Posted by RWA
Have cordially to disagree with that, PBL; and therefore with much of the rest of your anaysis.
Marcio, you are apparently also guilty of misconstruing also!
I was reconstructing what I take to be AI's position from the comments that Malinge made. It is a coherent reconstruction (as it has to be; I couldn't imagine AI or any other airframe manufacturer presenting dumb arguments on such an important issue).
And it has merit. What do you expect from those clever people?
Disagree with it all you like. Just attach the initials "AI" to it, not the initials "PBL".
Read it again next year, and the year after, when this is argued in court, and see if I am right that these arguments will be used, or wrong.
PBL
Last edited by PBL; 28th Sep 2007 at 17:24. Reason: Marcio did it too!
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Apples and Oranges
No, Marcio, it would not be a better measure. You reduce thrust to idle on each and every engine on each and every landing on each and every airplane, whether reversers are locked out or even if your airplane is not equipped with reversers at all.
then to Rev. Move the TL on the locked reverser to Idle, period. Now they changed to move both reversers to Rev...( Iguess to " show" that this is a "normal" landing... But remember the pilot from TAM who kept the locked reverser TL on Idle when landing in Congonhas?...He explained why.
I doubt if there is ONE case of pilots moving one TL to Rev and keeping the other on Climb in a landing without a reverser locked out. Do you know of any?...
All three disasters happened when the pilots were landing with one reverser locked out. I insist this is how it should be measured: in all landings with a reverser locked out, how many ended in disaster?...
PBL, why do you have to defend Airbus all the time?... Just a question of love at first sight? Or... after dating for a good while?...
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Marcio,
Allow me to have a little expertise in the subject I teach and consult on.
If you wish to show me I am making a mistake with statistical calculations, by all means do ahead and produce your argument. But please make it comprehensible. Suggesting I am choosing my sample space because I love Airbus is silly. Ask a statistician for hisher advice.
PBL
Allow me to have a little expertise in the subject I teach and consult on.
If you wish to show me I am making a mistake with statistical calculations, by all means do ahead and produce your argument. But please make it comprehensible. Suggesting I am choosing my sample space because I love Airbus is silly. Ask a statistician for hisher advice.
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Marcio,
No. The flare is exactly the same.
No, this is not what it is. As Lemurian said, "Only in your dreams".
The procedure during flare is, always was, and always will be, and has never been changed:
Move BOTH thrust levers to idle.
At the same time.
Together.
"As one."
Regardless of the state of any thrust reversers.
Completely independent of that is the procedure for what to do about reverse thrust after touchdown. In case of one locked-out thrust reverser, the procedure on touchdown has been to select reverse on the engine with the working reverser only.
There never was a procedure mentioning separately what to do with both thrust levers in the flare, as you keep implying. ("Move one to idle, Move the other to reverse." No!)
Bernd
Any pilot will know that landing with a reverser locked is different from landing with the two operating. It is a variant, a special situation.
before Airbus recommended to move the TL on the reverser working to idle and then to Rev. Move the TL on the locked reverser to Idle, period.
The procedure during flare is, always was, and always will be, and has never been changed:
Move BOTH thrust levers to idle.
At the same time.
Together.
"As one."
Regardless of the state of any thrust reversers.
Completely independent of that is the procedure for what to do about reverse thrust after touchdown. In case of one locked-out thrust reverser, the procedure on touchdown has been to select reverse on the engine with the working reverser only.
There never was a procedure mentioning separately what to do with both thrust levers in the flare, as you keep implying. ("Move one to idle, Move the other to reverse." No!)
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PBL,
About these landing statistics, what you are saying is that the fact that the TLs were misheld on three (four, if you count Phoenix) landings with engine reverse "locked" is a "coincidence"?
I'm sorry, but it doesn't make sense. If you want to know how many different accidents or incidents happened with an specific airplane on landings, then you count ALL landings.
Now, if you want to know how many accidents/incidents happened with an specific situation (one reverse inop), you measure this situation.
Using one simple analogy, consider gathering statitics on how many drunk drivers got involved in car accidents in a given time. Let's say 100 cars went through the toll booth on that given time. Of these 100 cars, 20 were involved in accidents. Of these 20 accidents, 10 were caused by drunk drivers.
Based on your calculations, only 20% of the cars had problems.
The fact that 10% of the drivers were drunk was a coincidence.
On my calculations, 50% of the accidents/incidents were caused by drunk drivers.
Basic statistics refers to sampling frames. And sampling how many accidents/incidents happened on landings with T/R inop is what is missing on your calculations.
Please, I don't want to teach the priest how to say the Mass, but I think that trying to justify what Mr. Malinge said, you forgot simple things. And remember, Mr. Malinge was directing his words to consumers. Public and press. Of course his "sampling" could only be the whole "universe" of landings. The numbers are more impressive.
But you know better. If I'm wrong, please educate me on this.
Rob
About these landing statistics, what you are saying is that the fact that the TLs were misheld on three (four, if you count Phoenix) landings with engine reverse "locked" is a "coincidence"?
I'm sorry, but it doesn't make sense. If you want to know how many different accidents or incidents happened with an specific airplane on landings, then you count ALL landings.
Now, if you want to know how many accidents/incidents happened with an specific situation (one reverse inop), you measure this situation.
Using one simple analogy, consider gathering statitics on how many drunk drivers got involved in car accidents in a given time. Let's say 100 cars went through the toll booth on that given time. Of these 100 cars, 20 were involved in accidents. Of these 20 accidents, 10 were caused by drunk drivers.
Based on your calculations, only 20% of the cars had problems.
The fact that 10% of the drivers were drunk was a coincidence.
On my calculations, 50% of the accidents/incidents were caused by drunk drivers.
Basic statistics refers to sampling frames. And sampling how many accidents/incidents happened on landings with T/R inop is what is missing on your calculations.
Please, I don't want to teach the priest how to say the Mass, but I think that trying to justify what Mr. Malinge said, you forgot simple things. And remember, Mr. Malinge was directing his words to consumers. Public and press. Of course his "sampling" could only be the whole "universe" of landings. The numbers are more impressive.
But you know better. If I'm wrong, please educate me on this.
Rob
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Quote:
(2) Reducing thrust to idle on flare is a basic task of basic airmanship that every pilot learns from his first flight. Introducing warnings concerning items of basic airmanship is not good practice.
As stated by pbl?
But can we all accept such statements, since it is good airmanship to land with the wheels down and when we forget there is a warning; do you wish to dispense with that?
(2) Reducing thrust to idle on flare is a basic task of basic airmanship that every pilot learns from his first flight. Introducing warnings concerning items of basic airmanship is not good practice.
As stated by pbl?
But can we all accept such statements, since it is good airmanship to land with the wheels down and when we forget there is a warning; do you wish to dispense with that?
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Thanks Rob!
I was looking for a simple analogy. Yours fits the bill.
bsieker,
Sorry, your post makes no sense. But... you ARE saying:
"In case of one locked-out thrust reverser, the procedure on touchdown has been to select reverse on the engine with the working reverser only."
Exact.
So it is NOT the procedure during a normal landing with both reversers functional.
It is the procedure with one locked-out thrust reverser. How often does that occur in normal airline operation? Fairly rarely, I would think.
So it's not exactly the procedure a pilot has in the forefront of his mind.
It's with such rarely if ever applicable procedures where a mistake can be made most easily, especially in difficult circumstances.
"Oh, locked-out T/R, so I don't touch the T/L". Sounds ludicrious, but in a high-stress situation..... ?
Locked-out T/R, T/L not retarded to idle, overrun.... it's now happened three (or four?) times.
I would like to see the statistics on the locked-out T/R, T/L not retarded to idle cases first, rather than the fatuous "3 cases in 30 million landings".
There are lies... there are damn lies.... and then there are statistics.....
I was looking for a simple analogy. Yours fits the bill.
bsieker,
Sorry, your post makes no sense. But... you ARE saying:
"In case of one locked-out thrust reverser, the procedure on touchdown has been to select reverse on the engine with the working reverser only."
Exact.
So it is NOT the procedure during a normal landing with both reversers functional.
It is the procedure with one locked-out thrust reverser. How often does that occur in normal airline operation? Fairly rarely, I would think.
So it's not exactly the procedure a pilot has in the forefront of his mind.
It's with such rarely if ever applicable procedures where a mistake can be made most easily, especially in difficult circumstances.
"Oh, locked-out T/R, so I don't touch the T/L". Sounds ludicrious, but in a high-stress situation..... ?
Locked-out T/R, T/L not retarded to idle, overrun.... it's now happened three (or four?) times.
I would like to see the statistics on the locked-out T/R, T/L not retarded to idle cases first, rather than the fatuous "3 cases in 30 million landings".
There are lies... there are damn lies.... and then there are statistics.....
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Original posted by Rob21 Maybe this can explain why on "nice" runways (POA) is SOP (TAM) both TLs to reverse and also (maybe) there is another "SOP" selecting only one TL to reverse on the "good" engine when runway is slippery (CGH).
At the present, two are the hypotesis: a interface/software defect or a human error. I suggest to discard the idea of the physical locking of the TL, because, with much probability, the reaction of the crew should have been different, since in this case they should be aware of the problem with the engine. In all this thread I didn't find any mention of the occurrence of events of the first type, so I think that this hypotesis is very improbable, even if not impossible. For the human error, since it is not the first time that it caused an accident (and we can ask ourselves how much times similar faults occurred without consequences), the probability is higher.
Original posted by PBL AI's position on (5) will be that, until the Congonhas accident, there was little evidence that failing to reduce thrust to idle on flare was an oft-repeated error. There were two incidents on record in (what AI claimed in its deposition) over 30 million fleet landings in 19 years.
I think that, with some probability, the mistake did originate from a discrepancy in the interfacing between machine and man, because the former operates only on the basis of the binary logic (1-0, yes-no), while the latter is educated to operate in this way, and often resume some logical processes under "frames" (in German: Gestalt). One of these could maybe be "one TL forward and one backward". It is only a hypotesis; I think that the important thing is that the professionals of the field can learn something from these tragic events, i.o. to improve the safety of aviation.