TAM A320 crash at Congonhas, Brazil
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3Ten,
thanks for the clarification. There's a very similar paragraph "INITIATION OF PROCEDURES" in the A320 FCOM, 3.02.01, P3, in the introduction to "ABNORMAL AND EMERGENCY" procedures.
Bernd
thanks for the clarification. There's a very similar paragraph "INITIATION OF PROCEDURES" in the A320 FCOM, 3.02.01, P3, in the introduction to "ABNORMAL AND EMERGENCY" procedures.
Bernd
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3Ten pointed out that
So as this is a landing you can initiate action straight away.
What should happen is that one of the pilots will read out the ECAM message as soon as it occurs; it's significance will be recognised and the corrective action to sort out the flight path can be taken immediately.
Tyro
- No action shall be taken (apart from audio warning cancel) until:
* The appropriate flight path is stabilized
* Normal procedures are applied
* At least 400 feet above the runway, in case of failure during approach, take off or go around,
* The appropriate flight path is stabilized
* Normal procedures are applied
* At least 400 feet above the runway, in case of failure during approach, take off or go around,
What should happen is that one of the pilots will read out the ECAM message as soon as it occurs; it's significance will be recognised and the corrective action to sort out the flight path can be taken immediately.
Tyro
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Whatever else, the aircraft left them with no real options to stop APART from closing the T/L (if that was the case) and that to me is WRONG, be it Boeing/Airbus/Embraer/Tupolev or whoever - WRONG. Plain and simple. Indeed, if Boeing have now gone that way, then I think they are WRONG too and I would not be surprised if folk are now looking rather carefully at what they have 'created'.
Forgive me if I have missed it in previous explanations - IF there had been those unlikely multiple failures in the sensors and with No2 T/L actually at IDLE but indicating CLB, what could the crew do to deploy the ground spoilers?
Forgive me if I have missed it in previous explanations - IF there had been those unlikely multiple failures in the sensors and with No2 T/L actually at IDLE but indicating CLB, what could the crew do to deploy the ground spoilers?
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Bsieker,
I don't have the whole A320 FCOM (have 2, 3 and 4th volumes).
Do you know where the above reference exactly is in the FCOM ? Or is it really in a separated diagram like that one refering to the other warning now implemented by AI ?
The warning display "ENG THRUST LOCKED" on the E/WD is inhibited on the ground, i. e. in all flight phases before liftoff, and all flight phases after touchdown.
Do you know where the above reference exactly is in the FCOM ? Or is it really in a separated diagram like that one refering to the other warning now implemented by AI ?
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TyroPicard,
I don't see where you could derive that statement from :
As an SFI, you probably have input-ted an engine failure / fire on short final...What did you expect from the crew ? A go around in order to have time to complete the ECAM procedure, or a continuation of the landing maneuver, postponing the fault treament until safely on the ground ? (multip[le answers possible, I'm no truth holder ).
For an airline the flleet of which include another brand, the criteria are very much valid...but fleet SOPs have to cater for general principles of handling.
BOAC,
Sorry but your post I referred to stipulated *Airbus gotchas*. and only them.
and you go on :
I seem to be repeating myself but re: AF744 in Faa, the same kind of misdhandling occurred, with the same results (no auto brakes, No spoilers, one engine in full G/A thrust). If I understand well, it doesn't count because nobody was hurt, right ? And the system remained as it was. Do I again sense some double standards or is it just due to my persecution complex ?
On the same incident, the crew also forgot to use the manual spoilers they had at their disposal, didn't they ?
What I'm trying to say is that there is no clear-cut solution when we're mainly dealing with human factors, especially when the originating factor is so outlandishly unthinkable that the whole system can, and did, collapse when it appeared.
The remedies are to be searched into the realm of behavioural science, in a safety-conscious mentality within all departments concerned, in training and good adherence to the procedures. All these are very apparently - and sorely - lacking in the events prior to the accident.
That AI shouidn't change anything is also open to question : for instance, as it seems that pilots rely on *feel* rather than confirm their actions through instruments, why not make the T/L grips conical, both small ends in the middle facing each other...Problem is that we will never know if that's the original mistake.
Change the *Retard* logic ? Why not ?
Regards.
3Ten pointed out that
Quote:
- No action shall be taken (apart from audio warning cancel) until:
* The appropriate flight path is stabilized
* Normal procedures are applied
* At least 400 feet above the runway, in case of failure during approach, take off or go around,
So as this is a landing you can initiate action straight away.
Quote:
- No action shall be taken (apart from audio warning cancel) until:
* The appropriate flight path is stabilized
* Normal procedures are applied
* At least 400 feet above the runway, in case of failure during approach, take off or go around,
So as this is a landing you can initiate action straight away.
- The *flight path* hasn't certainly been *stabilised*. It is my understanding that on landing, the *stabilisation* is acquired only when ground speed is under control. Don't your procedures - for instance - prohibit treament of a fire unless park brake is on ?
- Normal procedures are applied. A tough one on this case. I leave it to pros to judge...
- The 400 ft bit. They were under 400 ft, therefore inside the prohibition criterium. See Eric Parks'notes and you'll see that , somewhere in the US, that requirement is 1000 ft AFE.
As an SFI, you probably have input-ted an engine failure / fire on short final...What did you expect from the crew ? A go around in order to have time to complete the ECAM procedure, or a continuation of the landing maneuver, postponing the fault treament until safely on the ground ? (multip[le answers possible, I'm no truth holder ).
For an airline the flleet of which include another brand, the criteria are very much valid...but fleet SOPs have to cater for general principles of handling.
BOAC,
Sorry but your post I referred to stipulated *Airbus gotchas*. and only them.
and you go on :
Whatever else, the aircraft left them with no real options to stop APART from closing the T/L (if that was the case) and that to me is WRONG, be it Boeing/Airbus/Embraer/Tupolev or whoever - WRONG. Plain and simple. Indeed, if Boeing have now gone that way, then I think they are WRONG too and I would not be surprised if folk are now looking rather carefully at what they have 'created'
On the same incident, the crew also forgot to use the manual spoilers they had at their disposal, didn't they ?
What I'm trying to say is that there is no clear-cut solution when we're mainly dealing with human factors, especially when the originating factor is so outlandishly unthinkable that the whole system can, and did, collapse when it appeared.
The remedies are to be searched into the realm of behavioural science, in a safety-conscious mentality within all departments concerned, in training and good adherence to the procedures. All these are very apparently - and sorely - lacking in the events prior to the accident.
That AI shouidn't change anything is also open to question : for instance, as it seems that pilots rely on *feel* rather than confirm their actions through instruments, why not make the T/L grips conical, both small ends in the middle facing each other...Problem is that we will never know if that's the original mistake.
Change the *Retard* logic ? Why not ?
Regards.
Last edited by Lemurian; 1st Oct 2007 at 18:37. Reason: answer to BOAC
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Originally Posted by xulabias_bent
Do you know where the above reference exactly is in the FCOM ? Or is it really in a separated diagram like that one refering to the other warning now implemented by AI ?
Part 1 of the A320 FCOM is available for free download from The A320 section of smartcockpit.com. The documents under "SYSTEMS (Do not use for flight!)" is FCOM1.
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Part 1 of the A320 FCOM is available for free download from The A320 section of smartcockpit.com. The documents under "SYSTEMS (Do not use for flight!)" is FCOM1.
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Hi Lemurian
I thought this might open a small can of worms...
3Ten wrote in bold
The landing roll is not part of approach, take off or go around, it is a different flight phase. 400 ft rule applies to other flight phases.
And in the TAM situation, until you close No.2 T/L the flight path will never stabilize! So if you wait for a stable flight path before taking any further action ..... you overrun.
Surely the whole point of this new warning is to alert the crew to take immediate action?
Tyro
I thought this might open a small can of worms...
3Ten wrote in bold
* At least 400 feet above the runway, in case of failure during approach, take off or go around,
And in the TAM situation, until you close No.2 T/L the flight path will never stabilize! So if you wait for a stable flight path before taking any further action ..... you overrun.
Surely the whole point of this new warning is to alert the crew to take immediate action?
Tyro
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Tyro,
I gave you my interpretation, that happens to be shared by 3Ten (hence our respective airlines'SOPs).
Upon landing, the criterium for stabilisation is aircraft speed under control and generally ECAM procedures -if red- shouldn't be undertaken unless pbrake is on, airplane on the runway.
So, it's not only a matter of semantics.
I'm afraid you'll have to answer that for yourself.
What I can say is that, apart from it's debatable usefulness in a heavily stressed situation -and you are more qualified than I on that -, it goes against most the training that we've designed -learning by experience mostly - and tried to force into our pilots' make up.
A good SOP has no exceptions in its rules.
Did I hear "politics" ?
I gave you my interpretation, that happens to be shared by 3Ten (hence our respective airlines'SOPs).
Upon landing, the criterium for stabilisation is aircraft speed under control and generally ECAM procedures -if red- shouldn't be undertaken unless pbrake is on, airplane on the runway.
So, it's not only a matter of semantics.
Surely the whole point of this new warning is to alert the crew to take immediate action?
What I can say is that, apart from it's debatable usefulness in a heavily stressed situation -and you are more qualified than I on that -, it goes against most the training that we've designed -learning by experience mostly - and tried to force into our pilots' make up.
A good SOP has no exceptions in its rules.
Did I hear "politics" ?
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Originally posted by Rob21 As far as I could see, the landings registered on the FDR I had access were CGH, POA and CGH. I don't see any landings at Confins on the FDR. That's why I said that maybe there is an "SOP", or a special non official procedure for landing on that slippery 35L (It's downhill too, does anyone here remembers that?).
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Upon landing, the criterium for stabilisation is aircraft speed under control and generally ECAM procedures -if red- shouldn't be undertaken unless pbrake is on, airplane on the runway.
Whether the crew have the capacity to understand the significance of the ECAM warning under extreme pressure is another question altogether. For a crew to work out that lack of Ground Spoilers and Autobrake means "T/L not at Idle" is very unlikely IMHO, so this new warning has to be an improvement. It will need suitable training to highlight the fact that it exists - IMHO by instructor demonstration as you should not ask a trainee to make such a mistake on landing.
Cheers, Tyro
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TyroPicard
Not at all! Landing is included on the concept of approach. This procedural guidance simply translates as: NO **** CLOSE TO THE GROUND. Ok?
I think it's becoming obvious that many non pilots have little idea of the kind of workload and concentration is required in certain phases of flight. There are those here who are trying to understand these mechanisms, but others seem to parallel these moments with office tasks, wich they certainly are not.
The general idea is that (in approach) when you are landing the a/c, if something happens, either you go-around or land, first, then you deal with the problem. Lemurian, that's right, fire will be dealt with after parking brake on. I think all this shows how useless the sugested warning might actually get.
DozyWannabe
Providing we don't establish a direct connection between bad pilots and accidents, we're ok.
Regarding technology, please don't misunderstand me, I'm not against it. I'm merely against badly designed tech, and it exists, as the good one does. That's why I say I'm in favor of automaticaly retarding the other engine, if one thrust reverser is deployed on ground, but I'm against a new red warning for something that is an uncommon error and in a bad timing.
I've flown a *state of the art* aicraft before, that was the L1011, wich had latest tech for it's era, and didn't have many bugs. When I moved to the A310, there were a lot of things that I liked, lots of great improvements that help the pilot, but there are also a lot of bugs, things that weren't designed in the better sense. I like state of the art technology, and also think that Airbus had created some major advances in CRM, but I also think Airbus is lacking some pilot input in some stages of the design.
Cheers
The landing roll is not part of approach, take off or go around, it is a different flight phase. 400 ft rule applies to other flight phases.
I think it's becoming obvious that many non pilots have little idea of the kind of workload and concentration is required in certain phases of flight. There are those here who are trying to understand these mechanisms, but others seem to parallel these moments with office tasks, wich they certainly are not.
The general idea is that (in approach) when you are landing the a/c, if something happens, either you go-around or land, first, then you deal with the problem. Lemurian, that's right, fire will be dealt with after parking brake on. I think all this shows how useless the sugested warning might actually get.
DozyWannabe
Nope, there are good, medicre and bad pilots just as in any profession and in many accident cases it's as likely to be due to being in the wrong place at the wrong time (e.g TWA800, SR111, UAL232) as making a mistake (e.g KLM4805, AA1420, AA587). What I don't get is the insistence by some that the technology is there to thwart them rather than help them - which then becomes a self-fulfilling prophecy.
Regarding technology, please don't misunderstand me, I'm not against it. I'm merely against badly designed tech, and it exists, as the good one does. That's why I say I'm in favor of automaticaly retarding the other engine, if one thrust reverser is deployed on ground, but I'm against a new red warning for something that is an uncommon error and in a bad timing.
I've flown a *state of the art* aicraft before, that was the L1011, wich had latest tech for it's era, and didn't have many bugs. When I moved to the A310, there were a lot of things that I liked, lots of great improvements that help the pilot, but there are also a lot of bugs, things that weren't designed in the better sense. I like state of the art technology, and also think that Airbus had created some major advances in CRM, but I also think Airbus is lacking some pilot input in some stages of the design.
Cheers
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3Ten,
Wecome to the club...Come on ! You forget those pesty probs with the RCCBs, don't you?
But still I loved the lady and I'll miss her forever.
Cheers !
I've flown a *state of the art* aicraft before, that was the L1011, wich had latest tech for it's era, and didn't have many bugs.
But still I loved the lady and I'll miss her forever.
Cheers !
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3Ten:
I've flown a *state of the art* aicraft before, that was the L1011, wich had latest tech for it's era, and didn't have many bugs.
I've flown a *state of the art* aicraft before, that was the L1011, wich had latest tech for it's era, and didn't have many bugs.
That said, by all accounts it was a wonderful aircraft, although I never got the chance to board one. I think Lockheed poached the team that built the Trident Triplex Autoland to get the thing built, too.
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The wood for the trees!
BOAC
Yes this was my first post on this topic, I have however been reading "most" of the comments! That is why I made my post. We seem to have a hamster wheel going and the same old "airbus bashing" is being spouted.
You have lost credibility though when you stated
radical thought there close the thrust levers to stop!
The pilot flying left the thrust lever in the CLB detent NOT the aircraft or designers. He also did not immediately apply full manual braking when autobrake failed. Were these mistakes made due to poor training of this pilot or poor airmanship.
Yes we are all hoping an accident like this will not happen again but the main causes at the moment appear to be pilot induced so we should all be saying " I HAVE LEARNT ABOUT FLYING FROM THIS" I do not want to make those mistakes!!!
Yes this was my first post on this topic, I have however been reading "most" of the comments! That is why I made my post. We seem to have a hamster wheel going and the same old "airbus bashing" is being spouted.
You have lost credibility though when you stated
the aircraft left them with no real options to stop APART from closing the T/L (if that was the case) and that to me is WRONG,
The pilot flying left the thrust lever in the CLB detent NOT the aircraft or designers. He also did not immediately apply full manual braking when autobrake failed. Were these mistakes made due to poor training of this pilot or poor airmanship.
Yes we are all hoping an accident like this will not happen again but the main causes at the moment appear to be pilot induced so we should all be saying " I HAVE LEARNT ABOUT FLYING FROM THIS" I do not want to make those mistakes!!!
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A few points to answer yours, electricjetjock, and possibly show more clearly where we're coming from (some of us, anyway).
That's maybe 80% probable, but not certain. All we know is that the FDR recorded the lever as being in CLB.
Try as I might, I've never been able to fully to understand AB's various 'modes' - but I gather that one possiblilty is that (assuming the lever was misplaced) it ends up with a thrust lock and seeks to maintain the last commanded setting (which would presumably have been approach speed of say 140 knots). Since it would presumably be trying to do that with only one engine, it would (again presumably) have wound it up quite high.
I believe that another possibility is that the systems would have considered any setting above 'Idle' as being the next detent up (i.e. CLB).
The possibilities are that the pilot may indeed have left the lever in CLB; or he may have pulled it back to near 'Idle', but not AT 'Idle'; or he may have knocked it forward while reaching over it to get hold of and lift the reverser latch on No. 1.
I believe that according to the FDR, the pilot(s)' first step was to recycle the spoiler switch. That's pretty strong evidence that (having got reverse thrust) they thought that they had a spoiler malfunction. As to immediate braking, you'll know better than I - but my understanding is that applying the brakes at 140 knots would have been next to useless (and could very well have caused more problems than it solved).
That's the least understandable feature of all. The PF was a senior captain with over 10,000 hours, and a training pilot at that.
Agree entirely about that. But only as far as it goes - which isn't very far. Sure it's the duty of all concerned to learn from this accident - but that includes the designers. For some reason (probably basically an ergonomic one) around four A320 pilots appear to have made the same mistake; and, more important, not REALISED their mistake until it was too late.
So is it your view that all of us (pilots, designers, investigators, enthusiasts, the general public) should just leave everything as it is, and just HOPE that the same thing doesn't happen yet again - possibly with equally serious results?
If so, I for one can't possibly agree with you.
Originally Posted by electricjetjock
radical thought there close the thrust levers to stop!
The pilot flying left the thrust lever in the CLB detent NOT the aircraft or designers.
The pilot flying left the thrust lever in the CLB detent NOT the aircraft or designers.
Try as I might, I've never been able to fully to understand AB's various 'modes' - but I gather that one possiblilty is that (assuming the lever was misplaced) it ends up with a thrust lock and seeks to maintain the last commanded setting (which would presumably have been approach speed of say 140 knots). Since it would presumably be trying to do that with only one engine, it would (again presumably) have wound it up quite high.
I believe that another possibility is that the systems would have considered any setting above 'Idle' as being the next detent up (i.e. CLB).
The possibilities are that the pilot may indeed have left the lever in CLB; or he may have pulled it back to near 'Idle', but not AT 'Idle'; or he may have knocked it forward while reaching over it to get hold of and lift the reverser latch on No. 1.
Originally Posted by electricjetjock
He also did not immediately apply full manual braking when autobrake failed.
Originally Posted by electricjock
Were these mistakes made due to poor training of this pilot or poor airmanship.
Originally Posted by electricjetjock
Yes we are all hoping an accident like this will not happen again but the main causes at the moment appear to be pilot induced so we should all be saying " I HAVE LEARNT ABOUT FLYING FROM THIS" I do not want to make those mistakes!!!
So is it your view that all of us (pilots, designers, investigators, enthusiasts, the general public) should just leave everything as it is, and just HOPE that the same thing doesn't happen yet again - possibly with equally serious results?
If so, I for one can't possibly agree with you.
Last edited by RWA; 2nd Oct 2007 at 05:28.
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Manual Spoiler deployment?
Well, speedbrakes in the Bus in flap full is inhibited anyways. Only the auto gnd spoilers or the reverser-activated gnd spoiler is possible and require idle thrust and weight on wheels.
Would it help? Well, it took 11 secs for them to start braking. That's 770m gone... and potentially it's 770m gone before they put the spoilers out manually (if that feature was enabled)... Would they have stopped? Well with wet and/or 1/4 inch standing water, doing that with both engines into reverser, can result in excursion at anywhere between 5 - 80 kts. My opinion for this matter is, it's a nice option to have, but in the case of TAM, it would have still yielded excursion of >5kts and they'll end up on the road below instead of the building.
I completely disagree that the Bus is unsafe due to the gotchas and the no manual gnd spoiler deployment and the thrust lock etc... But the solution is simple, like ALL pax jetplanes, when about to touchdown, bring BOTH levers to idle!
I personally prefer Boeing's methods, but that doesn't mean the Bus ain't safe. Follow the SOPs correctly and they're all safe! Start missing things and you're already in that downward spiral towards disaster.
This whole accident has nothing to do with the bus' automation taking it away from the pilots, it's actually caused by the aircraft "giving it back to the pilot".
Back to the BOAC vs Lemurian discussions.
Bringing throttles to idle (all of them), is so intuitive that perhaps many have overlooked on what happens when one doesn't? What does the provision in Boeing do? As said, if it takes 11 secs for one to realize the gravity of the situation, spoilers wouldn't help, by then, retarding all engines and even the #2 reversers magically popping open wouldn't save the day!
The crux of the matter is, what happens when you don't bring both to idle? The problem here is not the aircraft systems, but the recommended procedures used.
With the previous landing in POA indicating both TLs selected into reverse, and the previous landing into CGH indicating only 1 TL into reverse, it shows that the diversity in the manipulation of the TLs is open enough to risk that a TL would be left in CLB... and someone here already claimed they experienced that!
As shown by the AF744 in Faaa mishap, Boeing too has the "throttles to idle or reverse otherwise you're screwed" methodology.
How much time do you need to realize the spoilers did not deploy be it in a Boe or a Bus? And how much time can one need when you're not quite with it?
I went on a 734 ride the other week into JOG (where everyone fears overrunning!)... 1st flight of the day for the crew. Touchdown and... spoilers nada! It took them 5 secs from spoilers nada to deciding to manually deploy spoilers THEN apply reversers. That's 350m down the drain. In the end, they just went... "down... spoilers nada... STOPPING! Reversers... spoilers deployed"...
That took, 3 secs... 210m down the drain.
They took the "bus method" on the last landing, sure, it was less runway wasted prior to commencing effective deceleration, BUT, it's open to risks similar the TAM 320 case.
I personally prefer the checking of spoilers prior to reverser deployment (ie: commitment to stop), but the Bus doesn't... it goes "select reverserS immediately", and it says "both reversers"... why? It is to reduce the risk of exactly what happened in TAM@CGH.
Whereas bringing BOTH to reverse would have deployed the spoilers regardless if they were armed or not.
This is a case if "because the runway's a bit risky in such a condition, let's start doing non-SOPs"... which in the end opens them to greater risk!
----
Avionista,
That scenario is possible although HIGHLY UNLIKELY... you gotta be an unlucky sod to end up in that situ.
Well, speedbrakes in the Bus in flap full is inhibited anyways. Only the auto gnd spoilers or the reverser-activated gnd spoiler is possible and require idle thrust and weight on wheels.
Would it help? Well, it took 11 secs for them to start braking. That's 770m gone... and potentially it's 770m gone before they put the spoilers out manually (if that feature was enabled)... Would they have stopped? Well with wet and/or 1/4 inch standing water, doing that with both engines into reverser, can result in excursion at anywhere between 5 - 80 kts. My opinion for this matter is, it's a nice option to have, but in the case of TAM, it would have still yielded excursion of >5kts and they'll end up on the road below instead of the building.
I completely disagree that the Bus is unsafe due to the gotchas and the no manual gnd spoiler deployment and the thrust lock etc... But the solution is simple, like ALL pax jetplanes, when about to touchdown, bring BOTH levers to idle!
I personally prefer Boeing's methods, but that doesn't mean the Bus ain't safe. Follow the SOPs correctly and they're all safe! Start missing things and you're already in that downward spiral towards disaster.
This whole accident has nothing to do with the bus' automation taking it away from the pilots, it's actually caused by the aircraft "giving it back to the pilot".
Back to the BOAC vs Lemurian discussions.
Bringing throttles to idle (all of them), is so intuitive that perhaps many have overlooked on what happens when one doesn't? What does the provision in Boeing do? As said, if it takes 11 secs for one to realize the gravity of the situation, spoilers wouldn't help, by then, retarding all engines and even the #2 reversers magically popping open wouldn't save the day!
The crux of the matter is, what happens when you don't bring both to idle? The problem here is not the aircraft systems, but the recommended procedures used.
With the previous landing in POA indicating both TLs selected into reverse, and the previous landing into CGH indicating only 1 TL into reverse, it shows that the diversity in the manipulation of the TLs is open enough to risk that a TL would be left in CLB... and someone here already claimed they experienced that!
As shown by the AF744 in Faaa mishap, Boeing too has the "throttles to idle or reverse otherwise you're screwed" methodology.
How much time do you need to realize the spoilers did not deploy be it in a Boe or a Bus? And how much time can one need when you're not quite with it?
I went on a 734 ride the other week into JOG (where everyone fears overrunning!)... 1st flight of the day for the crew. Touchdown and... spoilers nada! It took them 5 secs from spoilers nada to deciding to manually deploy spoilers THEN apply reversers. That's 350m down the drain. In the end, they just went... "down... spoilers nada... STOPPING! Reversers... spoilers deployed"...
That took, 3 secs... 210m down the drain.
They took the "bus method" on the last landing, sure, it was less runway wasted prior to commencing effective deceleration, BUT, it's open to risks similar the TAM 320 case.
I personally prefer the checking of spoilers prior to reverser deployment (ie: commitment to stop), but the Bus doesn't... it goes "select reverserS immediately", and it says "both reversers"... why? It is to reduce the risk of exactly what happened in TAM@CGH.
believe that according to the FDR, the pilot(s)' first step was to recycle the spoiler switch. That's pretty strong evidence that (having got reverse thrust) they thought that they had a spoiler malfunction. As to immediate braking, you'll know better than I - but my understanding is that applying the brakes at 140 knots would have been next to useless (and could very well have caused more problems than it solved).
This is a case if "because the runway's a bit risky in such a condition, let's start doing non-SOPs"... which in the end opens them to greater risk!
----
Avionista,
That scenario is possible although HIGHLY UNLIKELY... you gotta be an unlucky sod to end up in that situ.
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Try as I might, I've never been able to fully to understand AB's various 'modes'
I believe that another possibility is that the systems would have considered any setting above 'Idle' as being the next detent up (i.e. CLB).
The possibilities are that the pilot may indeed have left the lever in CLB; or he may have pulled it back to near 'Idle', but not AT 'Idle'; or he may have knocked it forward while reaching over it to get hold of and lift the reverser latch on No. 1.
I believe that according to the FDR, the pilot(s)' first step was to recycle the spoiler switch. That's pretty strong evidence that (having got reverse thrust) they thought that they had a spoiler malfunction
my understanding is that applying the brakes at 140 knots would have been next to useless (and could very well have caused more problems than it solved).
These sorts of technical *pearls* would be really, but really, hilarious if the main subject hadn't been the loss of nearly two hundred lives.
Per Ardua ad Astraeus
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To avoid further 'hot-under-the-collar' responses I will leave a/c manufacturer and type out of this post.
Now, there will no doubt be an outcry from our investigation and systems experts but to me it boils down to this:
One JOINT primary cause of the accident - a higher than idle thrust on No 2 engine, preventing ground spoiler deployment by the crew. (Note: I have no doubt the 'most likely cause', for many reasons, will be crew error for the power setting, but I do not think it will be actually determineable). It is also by no means certain that if the g/spoilers had been deployed OR the thrust reduced at some point there would not have been a bad accident, of course, due to the airfield terrain.
A host of secondary causes which have been well discussed.
So, we have to move forward. Those involved in training know what they have to do. Tyro and others eagerly await the 'Oriental' friend of marciovp giving us the way to simulate a SYSTEM failure in the simulator which might cause this power setting. In the meantime ALL pilots will hopefully have re-learned that all throttles should be closed on landing, and stay closed unless power is needed.
I suggest there should be a 'fail-safe' way to deploy ground spoilers as a 'must' in all a/c, be it a switch, lever or button, or some carefully designed logic function. Specific re-inforcement training needs to be given on this too. Could someone answer my question in Post #2541 please?
Particular aspects of a/c performance and procedures with and without T/R and specific airfield restrictions will no doubt be looked at.
I agree fully with PK-KAR's post - but note that there the high power setting is specifically blamed on the crew.
Now, there will no doubt be an outcry from our investigation and systems experts but to me it boils down to this:
One JOINT primary cause of the accident - a higher than idle thrust on No 2 engine, preventing ground spoiler deployment by the crew. (Note: I have no doubt the 'most likely cause', for many reasons, will be crew error for the power setting, but I do not think it will be actually determineable). It is also by no means certain that if the g/spoilers had been deployed OR the thrust reduced at some point there would not have been a bad accident, of course, due to the airfield terrain.
A host of secondary causes which have been well discussed.
So, we have to move forward. Those involved in training know what they have to do. Tyro and others eagerly await the 'Oriental' friend of marciovp giving us the way to simulate a SYSTEM failure in the simulator which might cause this power setting. In the meantime ALL pilots will hopefully have re-learned that all throttles should be closed on landing, and stay closed unless power is needed.
I suggest there should be a 'fail-safe' way to deploy ground spoilers as a 'must' in all a/c, be it a switch, lever or button, or some carefully designed logic function. Specific re-inforcement training needs to be given on this too. Could someone answer my question in Post #2541 please?
Particular aspects of a/c performance and procedures with and without T/R and specific airfield restrictions will no doubt be looked at.
I agree fully with PK-KAR's post - but note that there the high power setting is specifically blamed on the crew.
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BOAC:
The kind of "fail-safe" override you propose utterly negates the whole point of the automated protections (speedbrake inhibition placed there to prevent another Cali incident - where the pressure of suddenly finding themselves lost *and* in a canyon below MSA meant the pilots forgot they had deployed speedbrakes and couldn't climb out of there even with firewall thrust). Also as has been pointed out, even if the TAM crew had spoilers, in those conditions they would still likely have left the runway.
And in answer to your question, the option they have is one that, rumour has it, too few pilots seem to exercise these days - if the landing looks dicey, go around - divert if necessary.
The kind of "fail-safe" override you propose utterly negates the whole point of the automated protections (speedbrake inhibition placed there to prevent another Cali incident - where the pressure of suddenly finding themselves lost *and* in a canyon below MSA meant the pilots forgot they had deployed speedbrakes and couldn't climb out of there even with firewall thrust). Also as has been pointed out, even if the TAM crew had spoilers, in those conditions they would still likely have left the runway.
And in answer to your question, the option they have is one that, rumour has it, too few pilots seem to exercise these days - if the landing looks dicey, go around - divert if necessary.