ajaaron
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Tcas & ATC - This Is The Problem

Thu Jul 04, 2002 8:49 am

How feasible does this sound?

All very well that TCAS systems on 2 conflicting aircraft can resolve the situation and can get them out of a collision course safely - but the problem in this case was that ATC interfered - and told the Russian plane to descend - so naturally the Russian pilot will immediately ignore what TCAS is telling him as he thinks ATC know whats going on. As we know TCAS in the DHL 757 also said DESCEND, with tragic consequences.

Ironically if these aircraft did NOT have TCAS - the collision would have been avoided - Swiss ATC would have issued an immediate request to initiate and expedite descent to the Russian plane - and the DHL 757 - not having a clue about any potential conflict would have stayed at his level and there would have been no crash.

So the solution - ensure that all TCAS TA/RA alerts on board aircraft automatically notify ATC systems in the local FIR which indicate to the controller what TCAS is recommending to all aircraft involved in any poential conflict. This way the controller wil stay out of it and not intefere until (albeit watching what is going on o his radar screen) the conflict is resolved.
 
PPGMD
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RE: Tcas & ATC - This Is The Problem

Thu Jul 04, 2002 9:29 am

Nice idea but whos going to pay for it. Not me. Maybe when the FAA implements free flight we can see something like this.
At worst, you screw up and die.
 
Klaus
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RE: Tcas & ATC - This Is The Problem

Thu Jul 04, 2002 9:49 am

If pilots generally give priority to an emergency TCAS command, this problem doesn´t arise since both TCAS will already have coordinated correctly. And with what I´ve heard so far from the interviewed experts, that´s what´s supposed to happen.
 
bravo45
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RE: Tcas & ATC - This Is The Problem

Fri Jul 12, 2002 3:20 pm

First of all you cannoy have the clue that both TCAS have coordinated correctly immidiately at the arrising situation. Many experts says (especially the western) that TCAS command overrides the ATC and that the ATC needs not to be even notified. But mind you the Russians as I have heard (tell me if I am not correct) give more respect to the ATC command. Imaginaing this we can put ourselves into the feet of the Russian pilots who obviously got confused when he recieved 2 different and conflicting commands. I am not blaming anyone here but I do wonder if you can help me out why the Swiss tower only instructed the Russian to descent and that too twice. Whereas the DHL pliot was completely unaware of the confusion. Why was he not contacted also? I mean to sayif the ATC did interfere it seems to be incomplete comtrol of the situation (I am not blaming him but thats how I so far have understood it.Please clear me on this). Ajaaron's idea is good but yes finance is gonna be the problem if this is suggested. The point is, it didn't seemed to be a serious situation until the last few seconds. This should not have been a crash. Also if I can be told that the airspace was German but the Swiss were in control, Did any German controller had a hand in communicating. They are known to be the best in the world, is this gonna effect their reputation. Our wishes go out to all the victims and their families. I hope that we can make something good out of it.
 
Klaus
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Bravo45

Fri Jul 12, 2002 5:42 pm

Bravo45: Imaginaing this we can put ourselves into the feet of the Russian pilots who obviously got confused when he recieved 2 different and conflicting commands.

If the pilot was trained to give priority to an ATC command, he acted according to procedure, but still objectively wrong. My guess is that in an emergency conflict situation, ATC will be wrong much more often than TCAS. So generally prioritizing TCAS over ATC would seem sensible. Including training the pilots to expect and ignore a panicked ATC trying to cut in.


Bravo45: Also if I can be told that the airspace was German but the Swiss were in control, Did any German controller had a hand in communicating.

No. German airspace control got a conflict alert although they weren´t responsible for this segment. When they urgently tried to reach the swiss controller, they couldn´t get through since the Skyguide phone lines were down. And by then it was too late...
 
bravo45
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RE: Tcas & ATC - This Is The Problem

Fri Jul 12, 2002 8:12 pm

By "imagining" and getting into the russian pilot's feet I meant to say that a pilot who is told to prefer ATC over TCAS. I am not sure that is the case but as i said that I have heard it as so. Anyway an ATC controller with just two airplanes to control should have been able to handle them. I understand that his equipment may be wasn't full operational but still it wouldn't have been allowed to work if it wasn't capable of completing the job. Yeah generally TCAS should be a priority. Lot of small thing making this harmless condition a disaster. But I still wonder that the ATC interferance was not just confusing but also incomplete. Please also tell me why the controller only contacted the Rusian pilot and that too twice and not even once to the DHL pilot.
And comming back to the topic, yeah there are many problems with any new equipment like the TCAS. Although it is by now not all that new but this was its test, a situation where its absence may have averted this tragedy. I feel that the proper applications of any equipment should be made very clear to the whole world before airlines start using it. Especially in the case of such an intelligent equipment. And not just in any particular part of the world. Pilots from all around the world go to all different places and so unless there is a standard procedure fixed, tragedies can reoccur.
 
Klaus
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Bravo45

Fri Jul 12, 2002 11:02 pm

Bravo45: Anyway an ATC controller with just two airplanes to control should have been able to handle them.

The controller had five flights at this time, as far as I know. And the chain of events leading up to the accident started with him trying to contact the airport where one of the other three flights was about to land. Due to faulty phone lines, he lost much more time on that than anticipated. At least that´s what I know about it.


Bravo45: I understand that his equipment may be wasn't full operational but still it wouldn't have been allowed to work if it wasn't capable of completing the job.

They seem to have thought the added risks were "acceptable". The trouble with reducing error margins is that usually, those margins are there for a reason. And sadly, they would have made the difference. Easy to see for everyone with hindsight; Tougher to decide, possibly, with commercial pressure on operational planning...  Sad


Bravo45: Please also tell me why the controller only contacted the Rusian pilot and that too twice and not even once to the DHL pilot.

Until a qualified person tells us about procedures, my guess is that the ATC was in a bit of a shock and tried to "push through" the instruction he had intended for this flight anyway but wasn´t able to deliver in time...  Sad


Bravo45: And comming back to the topic, yeah there are many problems with any new equipment like the TCAS. Although it is by now not all that new but this was its test, a situation where its absence may have averted this tragedy.

TCAS worked flawlessly in this case. From what I´ve heard so far, it looks as if the problem was 100% procedure execution and training. I don´t see any argument from this accident that would speak against TCAS.


Bravo45: I feel that the proper applications of any equipment should be made very clear to the whole world before airlines start using it. Especially in the case of such an intelligent equipment. And not just in any particular part of the world. Pilots from all around the world go to all different places and so unless there is a standard procedure fixed, tragedies can reoccur.

I don´t have numbers, but as far as I´ve understood, TCAS priority is an element of pilot training almost everywhere. Almost.
 
bravo45
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RE: Tcas & ATC - This Is The Problem

Sat Jul 13, 2002 7:53 pm

Klaus:I don´t have numbers, but as far as I´ve understood, TCAS priority is an element of pilot training almost everywhere. Almost.

"Almost". Thats what I am saying. Until there is one pilot told to prefer ATC over TCAS, the risk is there. Waiting to happen when all these things click together.

Klaus:TCAS worked flawlessly in this case. From what I´ve heard so far, it looks as if the problem was 100% procedure execution and training. I don´t see any argument from this accident that would speak against TCAS.

I said that TCAS is a very intelligent device but whats the use of it when the users(pilots) don't know how to make the best of it. And thats is basically a problem related to the equipment and thats what I said. If the Russian pilot was trained to prefer ATC, then he shouldn't be blamed (that individual). he balme goes to all those who led him to this point and thinking. And all those who were supposed to correct him and didn't.

Klaus:Until a qualified person tells us about procedures, my guess is that the ATC was in a bit of a shock and tried to "push through" the instruction he had intended for this flight anyway but wasn´t able to deliver in time...

I too am not qualified but assuming that you are correct, I don; think that it was a very professional way to keep all the emphasis on only one of the two.

Klaus:The controller had five flights at this time, as far as I know. And the chain of events leading up to the accident started with him trying to contact the airport where one of the other three flights was about to land. Due to faulty phone lines, he lost much more time on that than anticipated. At least that´s what I know about it.

Night skies are always relatively emptu and the shift is easy neglecting the fact that night is supposesd to be for rest. But these ppl have moulded themselves to feel it as day. So whether 2 or five, he was certainly not under a very consumed situation. As you said "acceptable", and he did accepted it.
I am not blaming the controller entirely or jumping on to any conclusions. What I am saying is that the controller did play a crictical role here. Where as you as far as I have had the impression, blame only the russian pilot and that "shock" and "push though" that sounds like panic when I read your remark, is considered by by you as natural. Whereas for such people like these, there training teaches them to anticipate.
Anyway my final words will obviously be after the investigations but it seems like a tangle of errors by a lot of people.

 
Klaus
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Bravo45

Sat Jul 13, 2002 8:43 pm

Bravo45: I said that TCAS is a very intelligent device but whats the use of it when the users(pilots) don't know how to make the best of it. And thats is basically a problem related to the equipment and thats what I said.

No. Of course TCAS should be continually improved like any other system (including its "user interface"). But what´s happened was a problem of training to use those devices properly.


Bravo45: If the Russian pilot was trained to prefer ATC, then he shouldn't be blamed (that individual). he balme goes to all those who led him to this point and thinking. And all those who were supposed to correct him and didn't.

"Blame" is a pretty useless concept here. The decision about how to prioritize TCAS and ATC commands in pilot training was probably (my guess) made with the view of not wanting to overthrow "time-tested" standing procedures and just adding TCAS for compliance with european regulations.

Things like that can go well. Or they can lead to spectacular failure. But it´s not a clear-cut case of assigning "blame" to anyone. Even though it will probably be a good idea to modify bashkirian/russian pilot training in the future. But it still means juggling probabilities of failure on different levels.


Bravo45: I too am not qualified but assuming that you are correct, I don; think that it was a very professional way to keep all the emphasis on only one of the two.

Yeah, probably. But that´s exactly the problem with people under too much pressure: If you want everybody to act professionally all the time you need to give them enough space and time to work with.


Bravo45: Night skies are always relatively emptu and the shift is easy neglecting the fact that night is supposesd to be for rest. But these ppl have moulded themselves to feel it as day. So whether 2 or five, he was certainly not under a very consumed situation. As you said "acceptable", and he did accepted it.

I think the ongoing investigation will get a clearer picture of what kind of work environment Skyguide had. And yes, the controllers should not have accepted an understaffed shift with critical equipment out of order. It´s quite possible, though, that there was significant commercial pressure in play. We just can´t know yet. But it´s very clear that the whole planning of that shift was screwed up, badly. The chain of events apparently started right there.


Bravo45: I am not blaming the controller entirely or jumping on to any conclusions. What I am saying is that the controller did play a crictical role here. Where as you as far as I have had the impression, blame only the russian pilot and that "shock" and "push though" that sounds like panic when I read your remark, is considered by by you as natural.

No. I said the pilot probably acted according to his training, but with what we know from the analysis, objectively wrong. No space for assigning blame to him. But yet another indication of where to look for improvement.


Bravo45: Whereas for such people like these, there training teaches them to anticipate.

Of course the controller screwed up. And recognizing the nightmare of every controller materializing before his very eyes, he made yet another mistake. Training or no training; A state of shock can do the strangest things to you. The human brain seems to be bent on concentrating on a single way out in such a situation. But tunnel vision is the worst possible thing when you´re trying to get out of a complex problem.

So extra care should be taken not to let such situations arise in the first place. And apparently, they just took the risk...  Sad
 
bravo45
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RE: Tcas & ATC - This Is The Problem

Mon Jul 15, 2002 1:42 pm

Kalus:No. I said the pilot probably acted according to his training, but with what we know from the analysis, objectively wrong. No space for assigning blame to him. But yet another indication of where to look for improvement.

Certainly! That the ONLY positive point in an aviation tragedy, to make sure that the gaps that caused that are filled and that no other aircraft should come down because of the same reason.
Well I shouldn't have used the term "blame". But honestly what I feel is that politics happen all the time. This tragedy will have its own investigations. And Russians will comeup with their report and the Swiss or German or anyone else will come up with a report of their own. The chain of events would be almost the same. The conclusions will be where conflict will start. It has happened all the time everywhere. The reports try to prove their own persons as not to have made the fatal mistake, assigning the blame somewhere else. Even on this website in a forum, people were discussing the repoting of this accident by CNN that repoted that the Russian airliner had a" bad security record". And that one came down a few months back. I was as many others were outraged. The tragedy was not caused by the planes fault. But you know this happenes all the time. The Swiss would certainly defend the controller. The repots of ATR Roselawn case and the more recent one the Singapore Airlines case are a proving example.
I was just trying to make a remark staying neutral. I am not a Russian or having a lot of sympath for them. But I try not go after anyone that is not at fault. I hope you can understand it.


 
bravo45
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RE: Tcas & ATC - This Is The Problem

Mon Jul 15, 2002 1:46 pm

And the reason for all that I said and the fact that all of it directed towards the ATC was because of the fact that so many people here are blaming him with out using the word "blame", without any apparent reason. Surely this is a place to improve and if the standard procedure around most the world is to override the ATC and follow the TCAS, then the Russian airlines should have made sure that they do the same.
 
Klaus
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Bravo45

Mon Jul 15, 2002 8:08 pm

As far as I´ve heard so far, the swiss authorities aren´t defending Skyguide´s screwups. So there´s still hope lessons can be learnt without too much political interference. We´ll have to see about the russian side when it´s about training procedures.

I think this will take some time until the first mourning period will have passed.
 
bravo45
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RE: Tcas & ATC - This Is The Problem

Tue Jul 16, 2002 2:07 pm

I am not very in touch with the latest about the investigations of this accident. Nice to heard that that this is going without any politics. Would be nice to see the right things being put into place.
And yes certainly it will take enough time to let the mourning pass because it always takes time to have a complete analysis.
Have a great one all.

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