TAM A320 crash at Congonhas, Brazil
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For this unique accident, would the following memory items have saved lives?
Maintain directional control with rudder pedals
flaps-config 3
manually select speedbrakes extend
maximum manual toe brakes
both engines, fuel cutoff levers/switches-CUTOFF
KYAG-B
Maintain directional control with rudder pedals
flaps-config 3
manually select speedbrakes extend
maximum manual toe brakes
both engines, fuel cutoff levers/switches-CUTOFF
KYAG-B
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ELAC, a very erudite and educational post, thank you for that.
On another issue, who or what translated the transcript? Has anyone actually seen the original, Portuguese recording? If so, could you provide a link please?
When it was first shown here in Brazil it was in English and translated on-the-fly during the official presentation in parliament. Apparently that was how it came from the NTSB, but the crew and controllers spoke in Portuguese and I have to say that these translated versions make very little sense to me in linguistic terms.
I realise that a Portuguese version would be of limited interest to the majority here, but it would clear up a number of ambiguities for those of us who do speak the language.
On another issue, who or what translated the transcript? Has anyone actually seen the original, Portuguese recording? If so, could you provide a link please?
When it was first shown here in Brazil it was in English and translated on-the-fly during the official presentation in parliament. Apparently that was how it came from the NTSB, but the crew and controllers spoke in Portuguese and I have to say that these translated versions make very little sense to me in linguistic terms.
I realise that a Portuguese version would be of limited interest to the majority here, but it would clear up a number of ambiguities for those of us who do speak the language.
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Still on the subject of the CVR transcript..
What I would really like to read is the bit between 18:20:39.3 and 18:43:04.3, 23 minutes which presumably includes the approach briefing. This might just give a clue as to why TL2 was not moved to Idle.
TP
What I would really like to read is the bit between 18:20:39.3 and 18:43:04.3, 23 minutes which presumably includes the approach briefing. This might just give a clue as to why TL2 was not moved to Idle.
TP
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For this unique accident, would the following memory items have saved lives?
Maintain directional control with rudder pedals
flaps-config 3
manually select speedbrakes extend
maximum manual toe brakes
both engines, fuel cutoff levers/switches-CUTOFF
Maintain directional control with rudder pedals
flaps-config 3
manually select speedbrakes extend
maximum manual toe brakes
both engines, fuel cutoff levers/switches-CUTOFF
I don't mean to be facetious, but wouldn't memorizing:
At Landing:
Thrust Levers......Idle
be a far simpler way of solving the problem?
If the same situation were to occur again: go back and repeat the above.
It's the single fastest way to resolve the problem. Trying to move the flap, spoiler and engine master controls all while trying to maintain directional control and maximum braking would be a parlour trick on the best of days ... and beyond 99% of us on the worst.
There are only so many actions a human mind can process simultaneously, particularly under stress and any memory procedures we wish to suggest have to bear that limitation in mind.
ELAC
Last edited by ELAC; 4th Aug 2007 at 23:45.
@Elac
Nice Post Elac, must have taken alot of thought and effort. You are absolutely correct that this thread will sharpen the mind of AB FBW operators that is for sure.
There is one crucial factor in your post that you have missed, that is the runway was not only wet but slippery. Like thin ice was mentioned. In this case the extra % could be very different from that mentioned in the MEL. Dont forget the aircraft did actually slow down so the brakes must have been working.
The wet + 1/4" gives a landing run of 2600m without GS, which may still be optimistic.
BUT with ground spoilers 1655m. A massive difference of almost 1000 meters and very significant. A little more than the 600'-800' mentioned.
As for the Brakes - this will only be confirmed by the FDR as to how much pressure was getting to the wheels and on first application of Brakes. This of course is regulated by the anti-skid system.
TAM according to the posts here use Manual Brakes(Normally). The CVR which is incomplete makes no reference to an A/B selection. Sorry if I missed it on previous post. Any reference made to the FDR is only speculation at this stage. This is only important as if they were aware they had to use manual brakes then this should happen immediatley on touch down.
In the TW case autobrakes were selected and it took 18 secs for them to realise they were not actuating.
My money is on, the lack of spoilers which played the star role. Without them the aircraft was still producing lift, couple that with a slippery runway equals no braking action.
Jim
There is one crucial factor in your post that you have missed, that is the runway was not only wet but slippery. Like thin ice was mentioned. In this case the extra % could be very different from that mentioned in the MEL. Dont forget the aircraft did actually slow down so the brakes must have been working.
The wet + 1/4" gives a landing run of 2600m without GS, which may still be optimistic.
BUT with ground spoilers 1655m. A massive difference of almost 1000 meters and very significant. A little more than the 600'-800' mentioned.
As for the Brakes - this will only be confirmed by the FDR as to how much pressure was getting to the wheels and on first application of Brakes. This of course is regulated by the anti-skid system.
TAM according to the posts here use Manual Brakes(Normally). The CVR which is incomplete makes no reference to an A/B selection. Sorry if I missed it on previous post. Any reference made to the FDR is only speculation at this stage. This is only important as if they were aware they had to use manual brakes then this should happen immediatley on touch down.
In the TW case autobrakes were selected and it took 18 secs for them to realise they were not actuating.
My money is on, the lack of spoilers which played the star role. Without them the aircraft was still producing lift, couple that with a slippery runway equals no braking action.
Jim
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alemaobaiano ...
Sorry, I've only seen the English translation as well. If a Portuguese one surfaces interperative differents in how the words are translated could be very meaningful.
ELAC
Sorry, I've only seen the English translation as well. If a Portuguese one surfaces interperative differents in how the words are translated could be very meaningful.
ELAC
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ELAC" one must consider the remote possibility that throttles don't work properly...either in a cable controlled, or a fly by wire.
if pulling throttles to idle is a natural and normal thing, and it doesn't work, why waste time and try again?
my little checklist is for the case when moving throttles doesn't reduce thrust.
and again, I asked if it would have saved lives in this particular case? for some reason moving the throttles didn't work, or wasn't properly done .
have you ever had a throttle that didn't work? or a fuel cutoff lever that didn't cutoff the fuel? it has happened...and will probably happen again
if pulling throttles to idle is a natural and normal thing, and it doesn't work, why waste time and try again?
my little checklist is for the case when moving throttles doesn't reduce thrust.
and again, I asked if it would have saved lives in this particular case? for some reason moving the throttles didn't work, or wasn't properly done .
have you ever had a throttle that didn't work? or a fuel cutoff lever that didn't cutoff the fuel? it has happened...and will probably happen again
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hmmm... Elac,
This just doesn't seem to make sense for me.
Let's see if I've got the two different concepts down correctly:
AB in auto throttle mode:
TLs stay in CLB detent while actual throttle is managed by AT.
B in auto throttle mode:
TLs move according to throttle setting commanded by AT.
Both systems in approach / landing mode:
throttle setting managed by AT all the way down to the flare where it's set to idle, AT then disconnects.
AB in flare
System calls out "RETARD", PF moves both throttle levers out of the CLB detent and into the IDLE detent.
B in flare
PF monitors TL coming down with the actual throttle setting. In the flare they will be at IDLE, no further action necessary.
Now, if I have understood the way those systems work correctly, I have to conclude that the TLs not moving is a sine qua non for this accident. If the TLs are being brought back in accordance with the setting commanded by the AT, they will automatically end up in the IDLE position, nothing for the PF to fail.
Am I wrong that there is just no action for the PF to perform wrt the throttle levers in a conventionally designed aircraft?
If you were manually setting the thrust and leving one TL way forward, the engine would obviously not go to idle and you would just be floating along the runway until you finally realize it's time for TOGA.
I wonder how this accident could have happened with an airplane that was actually setting the throttle levers according to AT commands.
pj
If the latest information here quoting the Airbus AIT is accurate, then though the apparent failure of the PF to retard the TL2 to idle is the initiating factor for the accident, the fact of whether the TL's move a la Boeing or remain fixed as per Airbus is irrelevant.
Let's see if I've got the two different concepts down correctly:
AB in auto throttle mode:
TLs stay in CLB detent while actual throttle is managed by AT.
B in auto throttle mode:
TLs move according to throttle setting commanded by AT.
Both systems in approach / landing mode:
throttle setting managed by AT all the way down to the flare where it's set to idle, AT then disconnects.
AB in flare
System calls out "RETARD", PF moves both throttle levers out of the CLB detent and into the IDLE detent.
B in flare
PF monitors TL coming down with the actual throttle setting. In the flare they will be at IDLE, no further action necessary.
Now, if I have understood the way those systems work correctly, I have to conclude that the TLs not moving is a sine qua non for this accident. If the TLs are being brought back in accordance with the setting commanded by the AT, they will automatically end up in the IDLE position, nothing for the PF to fail.
Am I wrong that there is just no action for the PF to perform wrt the throttle levers in a conventionally designed aircraft?
If you were manually setting the thrust and leving one TL way forward, the engine would obviously not go to idle and you would just be floating along the runway until you finally realize it's time for TOGA.
I wonder how this accident could have happened with an airplane that was actually setting the throttle levers according to AT commands.
pj
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Thanks Jim ...
I think at this point we have to consider ascribing any absolute value to the runway surface condition as speculative. We don't have the data and it's hard to know what might be developed in that regard.
From the CVR the tower reports the runway as "wet and slippery" but the term slippery has no specific friction coefficient value that I'm aware of. If it was truly like thin ice (icy = .05 according to Airbus) then there would be more than one A320 and probably a few B737's as well off the runway that night.
The 15% increment for the ground spoilers should apply to all of the normal landing distance numbers that Airbus supplies as long as the actual braking co-efficients match the defined level of contaminant. All bets are off though if hydroplaning occurs or something else drops the co-efficient below the accepted values. In such a case the contribution of the ground spoilers would quite likely be higher, but the total stopping distance would be much higher as well making the over-run probably inevitable regardless of ground spoiler position. The critical question then would be why the braking co-efficient was lower than advised to the crew, not why the ground spoilers were not extended.
The other point would be that if "slippery" does denote a particular relative braking co-efficient that is below wet in Brazil then it would have been incumbent on the crew to consider whether the landing was still within safe parameters, particularly given the inop T/R. Relating to T/R deactivation, my MEL says "Refer to operations regulations for performance on wet, contaminated or slippery runway." (Interesting, there's that word slippery even though it's not defined!). So, specific consideration needs to be given in this case.
For most companies I know of the usual rule is that aircraft with inop T/R's are not dispatched to airports where contaminated conditions are likely to exist principally because contaminated runway takeoff performance usually requires consideration of reverse thrust. Landing performance is also a concern, but it's the inability to do the take-off that's usually the bigger problem.
In any event if there was any question of the runway surface having a braking co-efficient of lower than that defined by a "wet" condition, further discussion by the crew which we've seen no evidence of should have occurred before landing. As you say a CVR transcript of the briefing if available may be key. Were the autobrakes armed? If so, to what setting? If not, then even more pointedly ... why the delay in applying brakes manually?
Perhaps the ground spoilers not being extended played a role, but I'll stick with my concerns regarding the lack of a timely application of the brakes as being the biggest factor subsequent to the initial failure to retard T2.
Only a thorough and professional investigation will tell us about that for sure or about the actual runway condition. Until we know those things we're all just guessing.
ELAC
I think at this point we have to consider ascribing any absolute value to the runway surface condition as speculative. We don't have the data and it's hard to know what might be developed in that regard.
From the CVR the tower reports the runway as "wet and slippery" but the term slippery has no specific friction coefficient value that I'm aware of. If it was truly like thin ice (icy = .05 according to Airbus) then there would be more than one A320 and probably a few B737's as well off the runway that night.
The 15% increment for the ground spoilers should apply to all of the normal landing distance numbers that Airbus supplies as long as the actual braking co-efficients match the defined level of contaminant. All bets are off though if hydroplaning occurs or something else drops the co-efficient below the accepted values. In such a case the contribution of the ground spoilers would quite likely be higher, but the total stopping distance would be much higher as well making the over-run probably inevitable regardless of ground spoiler position. The critical question then would be why the braking co-efficient was lower than advised to the crew, not why the ground spoilers were not extended.
The other point would be that if "slippery" does denote a particular relative braking co-efficient that is below wet in Brazil then it would have been incumbent on the crew to consider whether the landing was still within safe parameters, particularly given the inop T/R. Relating to T/R deactivation, my MEL says "Refer to operations regulations for performance on wet, contaminated or slippery runway." (Interesting, there's that word slippery even though it's not defined!). So, specific consideration needs to be given in this case.
For most companies I know of the usual rule is that aircraft with inop T/R's are not dispatched to airports where contaminated conditions are likely to exist principally because contaminated runway takeoff performance usually requires consideration of reverse thrust. Landing performance is also a concern, but it's the inability to do the take-off that's usually the bigger problem.
In any event if there was any question of the runway surface having a braking co-efficient of lower than that defined by a "wet" condition, further discussion by the crew which we've seen no evidence of should have occurred before landing. As you say a CVR transcript of the briefing if available may be key. Were the autobrakes armed? If so, to what setting? If not, then even more pointedly ... why the delay in applying brakes manually?
Perhaps the ground spoilers not being extended played a role, but I'll stick with my concerns regarding the lack of a timely application of the brakes as being the biggest factor subsequent to the initial failure to retard T2.
Only a thorough and professional investigation will tell us about that for sure or about the actual runway condition. Until we know those things we're all just guessing.
ELAC
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Veja Magazine
The weekly magazine VEJA is coming back adamant. They say that the voice recorder and the fligh recorder agree that the T/L #1 was not moved to idle and this caused all the chain of events. It seems that
the software of this plane only warned "Retard" three times and then stopped, while the newer software would continue to warn the pilot of the wrong T/L position on motor #1. Could this be?
the software of this plane only warned "Retard" three times and then stopped, while the newer software would continue to warn the pilot of the wrong T/L position on motor #1. Could this be?
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Am I wrong that there is just no action for the PF to perform wrt the throttle levers in a conventionally designed aircraft?
You seem intent on believing what you want to believe regardless of the facts.
On *most* conventionally designed aircraft you have to pull the thrust levers to idle when you flare, there is no such thing as autothrust in a very large percentage of airplanes. That's the way it's worked on the B727 and every other non-FBW aircraft I've ever flown. Even on most conventional aircraft with autothrust, such as the B757, this is usually disconnected at the time the pilot disconnects the autopilot leaving the thrust levers under manual control. If you don't pull them back yourself when you land they produce whatever thrust the lever demands. This was never pointed out to me in training as a design flaw.
The difference you seem to be getting at is between the Airbus and certain recent Boeings which are landed manually with autothrust active. The Boeing TLs move whereas the Airbus ones do not. There are arguements for either system when looked at holistically, but the Airbus system is not one iota more complicated or different in philosophy in this particular respect than a B757, B727 or a DC-3 for that matter. You want idle thrust, pull the levers to idle. Simple.
ELAC
Last edited by ELAC; 4th Aug 2007 at 22:42.
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Thanks a lot ELAC for your very insightful posts. You raise a valid point.
The lack of ground spoilers may of course contribute significantly to hydroplaning as the aircraft still creates considerable lift in CONF FULL without spoilers, thus there will be relatively little weight on wheels.
Especially on contaminated runways, the spoilers contribute three-fold to good deceleration performance:
a - By creating additional drag at higher speeds
b - By dumping lift and thus creating higher normal force ("weight") on the wheels
c - b has the additional effect of avoiding hydroplaning and thus creating a much more favourable friction coefficient.
(Friction = Friction coefficient times normal force)
Originally Posted by ELAC
All bets are off though if hydroplaning occurs or something else drops the co-efficient below the accepted values. In such a case the contribution of the ground spoilers would quite likely be higher, but the total stopping distance would be much higher as well making the over-run probably inevitable regardless of ground spoiler position.
Especially on contaminated runways, the spoilers contribute three-fold to good deceleration performance:
a - By creating additional drag at higher speeds
b - By dumping lift and thus creating higher normal force ("weight") on the wheels
c - b has the additional effect of avoiding hydroplaning and thus creating a much more favourable friction coefficient.
(Friction = Friction coefficient times normal force)
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You seem intent on believing what you want to believe regardless of the facts.
On *most* conventionally designed aircraft you have to pull the thrust levers to idle when you flare, there is no such thing as autothrust in a very large percentage of airplanes. Well, at least that's the way it's worked on the B727 and pretty much every other non-FBW aircraft I've ever flown.
Even on most conventional aircraft with autothrust, such as the B757, this is usually disconnected at the time the pilot disconnects the autopilot leaving the thrust levers under manual control. If you don't pull them back yourself when you land they produce whatever thrust the lever demands.
Funnily enough this was never pointed out to me in training as a design flaw.
The difference you seem to be getting at is between the Airbus and certain recent Boeings which are landed manually with autothrust active. The Boeing TLs move whereas the Airbus ones do not. There are arguements for either system when looked at holistically, but the Airbus system is not one iota more complicated or different in philosophy in this particular respect than a B757, B727 or a DC-3 for that matter.
the way they leave the TL when autothrust disconnects.
You want idle thrust, pull the levers to idle. Simple.
But for some reason, this has not happened here.
I've said earlier that good system design means to avoid error, tolerate error or at least fail gracefully.
It's just my feeling that a system that leaves the TLs in a position that is directly reflecting the thrust setting at AT disconnect does avoid the possibility of the error at hand completely. Not pulling back a TL is just a non issue (even though I agree with you, it's still an error). The system of non-moving TLs however seem first to create the possibility for this error. Question is from there, how well does it tolerate the error and how gracefully does it fail.
Don't get me wrong, I don't want to bash Airbus, why should I?
But at the same time, I think that there's evidence that there was more than one incident where this system has been mishandled, thus I think it's only fair that it is questioned.
Also, I would be (really) interested in what the rationale behind that design decision was. When introducing a whole new paradigm, someone surely must have had a good reason for it.
pj
Marciovp
I cannot comment on the latest software but if you look at the Taipei report you'll find a note that the "Retard" warning could apparently be silenced by only ONE T/R being applied, hence that report's recommendation of a mod. Seems sensible but assume not done here. It does seem illogical (& arguably counterproductive) to have a warning which is cancelled without the problem having been removed, if that is what in fact happens. Caveat: I'm no AB software expert..
I cannot comment on the latest software but if you look at the Taipei report you'll find a note that the "Retard" warning could apparently be silenced by only ONE T/R being applied, hence that report's recommendation of a mod. Seems sensible but assume not done here. It does seem illogical (& arguably counterproductive) to have a warning which is cancelled without the problem having been removed, if that is what in fact happens. Caveat: I'm no AB software expert..
And really, this is the way that we pilots want it to be. Almost all of the high vitriol here is about how it must be the pilot who controls the aircraft and not the computer. In this event it seems the aircraft gave the pilot everything he commanded through his actions (REV on #1, approach power on #2, later manual brakes when applied), the problem was that those initial actions were not sufficiently unambiguous for the system to deduce that a landing was intended and that automatic ground spoiler and braking should occur, as opposed to requiring further manual inputs from the pilot to make that happen
I am still baffled that presented with such a "not sufficiently unambiguous" situation the system, by design, did nor raise all kind of unambiguous warnings to the crew to make sure they would be 100% aware not to expect automatic spoiler extension, auto braking and more generally that they were doing something clearly wrong.
I understand there is some "desirable" software update that might have achieved some sort of warning but apparently it was not installed on this aircraft. I would be really interested into the logic that precluded this upgrade to be categorized as urgent and mandatory.
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Software
Max Tow
I am interested in this question of the software, and the warning voice and light signs in the cabin when this problem develops. I read somewhere that Airbus had corrected that ,and offered a new software that would sound a persistent voice and light signs with the "Retard". When I read this it was said that TAM did not updated the software in its planes. But this is to be confirmed because as you know there are many theories floating around.
Airbus now is sending someone to Brazil to follow the investigations, and I am hoping that CENIPA (the Air Force investigative and preventive agency, will pursue this issue). Perhaps even the House of Representatives Investigative Committee could ask this question about the latest software in that plane. They asked many questions to the president of TAM but this was not one of them. It is interesting that the ANAC (National Agency for Civil Aviation) has a recommendation that when landing in a wet runway both reversers should be activated in full. This was asked to the president of TAM who said that the Airbus Manual was the main determinant, and it said that the airplane could land without problems with one reverser locked out for a period of 10 days prior to maintenance. But just to be sure I would love to have someone asking the Airbus representative about new softwares after the two previous accidents. Will let you all know if I come to an answer.
I am interested in this question of the software, and the warning voice and light signs in the cabin when this problem develops. I read somewhere that Airbus had corrected that ,and offered a new software that would sound a persistent voice and light signs with the "Retard". When I read this it was said that TAM did not updated the software in its planes. But this is to be confirmed because as you know there are many theories floating around.
Airbus now is sending someone to Brazil to follow the investigations, and I am hoping that CENIPA (the Air Force investigative and preventive agency, will pursue this issue). Perhaps even the House of Representatives Investigative Committee could ask this question about the latest software in that plane. They asked many questions to the president of TAM but this was not one of them. It is interesting that the ANAC (National Agency for Civil Aviation) has a recommendation that when landing in a wet runway both reversers should be activated in full. This was asked to the president of TAM who said that the Airbus Manual was the main determinant, and it said that the airplane could land without problems with one reverser locked out for a period of 10 days prior to maintenance. But just to be sure I would love to have someone asking the Airbus representative about new softwares after the two previous accidents. Will let you all know if I come to an answer.
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Just a quick question.
I have seen this "the airplane could land without problems with one reverser locked out for a period of 10 days prior to maintenance." statement before on other sites.
What does this actually mean? Why 10 days not X cycles, or X hours in flight?
What does this actually mean? Why 10 days not X cycles, or X hours in flight?
Atakacs/Marciovp
Totally agree - IF it is still the case years after Taiwan that warning is extinguished even if one TL not retarded, it's an obvious question to ask AB given the previous crashes with one TR locked out. A comment was made earlier that the reported 4 "TL mishandling with one TR locked out" accidents in umpteen million flight hours may be coincidence, however we are not talking about normal ops but an apparent propensity to error when one TR locked out. We have already had 2 other reports on this thread of similar incidents from which recovery was made, so I guess it's fair to say that the confusion is a more common occurrence than just those with catastrophic consequences. This leads to the still unclear issue (from correspondence here) as to whether all operators MELs now say use both TR even if one locked, which ought presumably to help eliminate this particular combination of circumstances.
Conversely, one might also turn the issue around and ask whether there have been any more than one (Warsaw) A320 TL mishandling accidents where both TR's were functional. If not, and picking a purely hypothetical ratio of 1 in every 200 sectors where the a/c ops with a TR locked out, it would then be 800 times more likely that TL induced errors lead to accidents when one TR locked out. Please feel free to rip apart the logic at this early hour of the morning -of course 4 accidents might not be an adequate statistical sample but I wouldn't be surprised to see an AD for the AB mod mentioned..
Octavius
For non-deteriorating deferrable defects, it is quite common to use a calendar period as this allows for planning of maintenance inputs and spares delivery. If one were to use cycles/hours, the usual day to day operational aircraft changes would make forward planning more difficult. For more urgent defects, and those where further usage related deterioration is likely (e.g. brake/tyre wear or engine blade tip clearances) a cycle or hour limit is obviously appropriate.
Totally agree - IF it is still the case years after Taiwan that warning is extinguished even if one TL not retarded, it's an obvious question to ask AB given the previous crashes with one TR locked out. A comment was made earlier that the reported 4 "TL mishandling with one TR locked out" accidents in umpteen million flight hours may be coincidence, however we are not talking about normal ops but an apparent propensity to error when one TR locked out. We have already had 2 other reports on this thread of similar incidents from which recovery was made, so I guess it's fair to say that the confusion is a more common occurrence than just those with catastrophic consequences. This leads to the still unclear issue (from correspondence here) as to whether all operators MELs now say use both TR even if one locked, which ought presumably to help eliminate this particular combination of circumstances.
Conversely, one might also turn the issue around and ask whether there have been any more than one (Warsaw) A320 TL mishandling accidents where both TR's were functional. If not, and picking a purely hypothetical ratio of 1 in every 200 sectors where the a/c ops with a TR locked out, it would then be 800 times more likely that TL induced errors lead to accidents when one TR locked out. Please feel free to rip apart the logic at this early hour of the morning -of course 4 accidents might not be an adequate statistical sample but I wouldn't be surprised to see an AD for the AB mod mentioned..
Octavius
For non-deteriorating deferrable defects, it is quite common to use a calendar period as this allows for planning of maintenance inputs and spares delivery. If one were to use cycles/hours, the usual day to day operational aircraft changes would make forward planning more difficult. For more urgent defects, and those where further usage related deterioration is likely (e.g. brake/tyre wear or engine blade tip clearances) a cycle or hour limit is obviously appropriate.
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MaxTow,
Warsaw was not related to thrust lever settings.
The accident report states
but also
http://www.rvs.uni-bielefeld.de/publ...aw-report.html
pj
edited to remove clutter
Warsaw was not related to thrust lever settings.
The accident report states
incorrect decisions and actions of the flight crew taken in
situation when the information about windshear at the approach to the runway was received.
situation when the information about windshear at the approach to the runway was received.
In emergency, the crew is unable to override the lock-out and to operate
pj
edited to remove clutter