Ueberlingen collision Trial started
 

The trial is prosecuting for the moment 8 Skyguide ( the Swiss ATC Service provider ) officials. after the collision that occured on 02 July 2002.

It Started last Tuesday, with the audition of 2 senior management staff of Zurich ACC, who rejected all responsibility, and declared that the " fault" lies solely with the air traffic controller on duty that night ( who unfortunately will not be there to defend himsef ).

But the judge seem to want to look deeper into the system, and he could overturn some stones.

The trial is expected to last a few weeks.

"It Started last Tuesday, with the audition of 2 senior management staff of Zurich ACC, who rejected all responsibility, and declared that the " fault" lies solely with the air traffic controller on duty that night ( who unfortunately will not be there to defend himsef )."

As I remember it, this ATCO was left on his own, without STCA, doing two jobs on radar screens separated by 20 yards and some of the telephone system on MTX? And they want to blame him? In my view his principal error was to allow management to put him in that position in the first place.

If they get away with pinning the blame on this ATCO then every ATCO out there is in deep water: It means ATSPs can run their system in a seriously flawed state without being liable when the guy on the front line is unable to make up for those inadequacies. It is not the job of the ATCO to make up for shortcomings in ATC system design and that he should have been asked to do so is unacceptable.

If their defence wins the day then it is time to hang up the headset.

:mad: :mad:

.4

Sounds as though we may have some parallels here with the 1976 Zagreb collision..

Whilst it is true that ATC are primarily responsible for correct vertical separation of en-route IFR traffic, TCAS was introduced as an essential safety complement for those rare occasions when ATC errors occur.

But TCAS is only of any use if the crews know how to use it correctly!!

TCAS RA directions always override ATC instructions!

On 1 Jul 2002, the Bashkirian Airlines Tu 154 and DHL Boeing 757 were on a collision course at FL360. This is what happened in the 50 seconds following the first TCAS Traffic Advisories:

21:34:42 Both aircraft receive TAs
21:34:49 ATC instructs Tu 154 to descend to FL350
21:34:56 Boeing 757 issued “Descend, descend” RA. Crew responds correctly
21:34:56 Tu 154 issued “Climb, climb” RA. Crew continues to descend
21:35:03 ATC instructs Tu 154 to increase descent rate
21:35:10 Boeing 757 issued “Increase descent” RA. Crew responds correctly
21:35:19 Boeing 757 advises ATC they are responding to TCAS RA
21:35:24 Tu 154 issued “Increase climb” RA. Crew continues to descend
21:35:32 Both aircraft collide overhead Überlingen

I wouldn't read too much into the fact that the Skyguide officials have laid the blame at the door of the ATCO. Given that they are facing criminal charges it's hardly surprising that the central plank of their defence is that the blame lies solely with the late Peter Nielsen. It doesn't of course, in reality, but given this is a criminal trial the defendants don't need to prove anything, least of all that someone other than them was responsible. So don't infer that an acquittal by the criminal court is an imputation of responsibility on the controller.

In reality what happened that night was a combination of systemic failings at Skyguide, serious mistakes by Nielsen which arguably amounted to gross negligence, national differences in SOPs which led the Bashkirian crew to ignore the TCAS RA, and just plain bad luck.

Wedge

It seems that you have a greater grasp of the detail of this than I do. You have made a strong statement about Peter Neilsen's part in the accident - I wonder if you would share the detail of his mistakes? Could it in any way be argued that his mistakes were provoked by the situation he was in?

What I find incredible is that (as I understand it) he was required to be monitoring 2 radar screens, 20 yards apart by himself. Surely, that is an unacceptable situation for any ATCO to be put in and it ought not to get through the safety case?

As far as the management is concerned, it seems to me that they willingly removed a number of the safety nets in order to get essential work done without first providing mitigation of the increased risks. That action directly exposed the system and Mr Neilsen. Regardless of what other errors were made, that strikes me as negligent.

.4

Oh dear ! The subject of this post is the trial, not to re-do the investigation.
I suggest that you look again in the Bfu report to find your answers.

TCAS flaws have been highlighted as a result of this collision and it is very simplist to suggest, as it is done here, that the757 crew responded correctly and the Tu154 did not.

As to the supposed "gross negligence" of the controller on duty, let me just say that this view is not shared by the vast majority of the people involved in the investigation, and even ,as far as I can see, also not by the defence lawyers.
How the judge will go is still uncertain.

BEagle... Rightly or wrongly, I interpret your post as putting the blame on the Russian Flt Crew :eek:
Can you confirm you are basing that allegation on definite knowledge that at the time, the Russian Company SOPs, authority legislation, equipment and Training were of a similar status to that on which you base your statement?
Without having investigated the accident in great depth, but to some degree, then it seems there were ATC "system" failings that enabled that system to fail. That TCAS then failed as well was unfortunate, but it was a relatively "immature" system, particularly for say some former "Eastern Block" nations/operators, and "rules" to which you and I operate, especially today, might not have applied then, to that crew... :sad:

At the time, my company SOPs were that a TCAS RA was to be followed unless the target could be identified and was no threat. That SOP has since changed removing the proviso. Other companies have done the same.

Re the Russian SOP w.r.t. TCAS: I recall from some discussion groups a few years back that there had been a dispute on the flightdeck of the Tu-154 between the captain, PF and the check captain, acting as the PNF. The check captain allegedly overrode captain's decision to heed the TCAS and insisted to descend as instructed by ATCO, exactly in line with the Tu-154 manual. Also as far as I remember, the main SSR was u/s and a backup unit was being used (not sure if that meant the processor-screen or a complete radar-feed).

Found the report, here, in German, it states three systemic causes: the TCAS issue compounded by failure to standartize (in the end, who will pressure Russia) requirements and harmonize units, and the other two are down to the Skyguide management. I hope the name of P. Nielsen comes clear out of this trial too.

Being a PPL amateur I had the chance 4 years ago to buy a sim hour in the TU5M sim of S7 for peanuts just out of curiousity. The sim then had TCAS but it was not included in any checklist whether it works or not so I asked the pro riding with me about it. His statement was more or less "oh, yes, we have it but if it is u/s we go anyway". This, well noted, on a "better" airline going to the "West" frequently.

Question ímho is therefore - did Bashkirian drivers ever go a REAL trainig in it, ie did they really learn to obey it???

(NOT blaiming them but possibly their company!!!)

In my company (a well known UK one!) it is permissible to fly with TCAS u/s for a period of time, and I have done so a few times. NB we all used the fly without TCAS pretty safely a few years back, and we still have Mode C v the other aircraft's TCAS.
If you can get 2 TCAS u/s aircraft in the same part of the sky AND an ATC "system" failure sufficient to cause a collision, it's not your day :(
As HF says, even in the West, training and SOPs have been tightened post this incident. In the East, life tends to be more "control based" and a larger cultural change needed to blindly obey a piece of kit contrary to an ATCO. Hanging the Russian crew out to dry (also dead) is as bad, IMHO, as hanging the ATCO out...

And yet, something all too similar happened again.(Brazil)
I pray the aftermath of the Uberlingen collision doesn't happen again.(with respect to Mr Nielsen's fate.)
At least in part due to the media, IMHO.

Although there was an ATC failure, Mr. Nielsen tried his damndest to cope as best he could.

The Bashkirian Airlines crew had all received TCAS training and the TCAS operating manual used for their course was quite specific concerning RAs and contradictory ATC clearances - even though the Tu-154 manual was rather less so. There was a 'seat swap' in progress as the co-pilot got back into his seat after the first TA - he made the point several times that the subsequent RA was very specifically ordering a climb......

Read the report in full, I would suggest.

This question has been troubling me since the accident, hopefully someone more knowledgeable of ATC than myself can resolve it for me.

Was it not the case that the Tupolev had been allowed by the previous sector to cruise at a non-standard level?

That being so, on transfer to the sector in which the accident took place, should that not have been made clear to the receiving sector?

Naively, I would'nt have that you'd be handed over to another sector at a non-standard level without either their acceptance, or an instrution to adjust ( climb/descend ) to a standard level for the sector you are entering.

There are many areas of the world where non-standard level cruise is widely-used, and indeed encouraged. I've used it myself on several occassions, but always in the perhaps misguided notion that in addition to TCAS, we enjoyed this further protection.

Any thoughts?

According to MEL of the aircraft I've flown, it is allowed to dispatch with TCAS inop, but ATC permission has to be sought and in Europe it is usualy given.

That piece of kit is intended to save lives when conventional methods of aircraft separation have failed and that's what everyone needs to know, regardless of his cultural background. I find it hard to believe that russian peacetime culture puts obedience to authority above self-preservation. More likely the russian crew was never fully acquainted with the TCAS principles of operation and procedures to be followed in case of RA. Not their fault, mind you - it was fault of their trainning dept and Russian CAA.

Mine didn't. Since we got TCAS in 2000. it was always policy to follow TCAS RA unless it sends you toward terrain, thanks to safety pilot who understood TCAS very well.

It was not immature and it didn't fail over Ueberlingen - it worked as designed. My apologies for perhaps being narrow-minded, but I can't see flaws in TCAS itself in this case.

Indeed, at ZAG ACC there were only 2 ATCOs covering consoles usualy occupied by 6 of them and just as Adria DC-9 was handed over from mid to upper sector an told to stop sqawking alt (per procedure at the time) one of them had to take physiological break. It didn't help much that the overworked remaining ATCO panicked and issued instructions to DC9 crew that lead to collission. He was later sentenced by Yugoslav court to 5 years in prison but was released after year and half, after retrial. Other controllers and ATC organzation were acquitted at the first trial.

Not quite similar. To have coordinated TCAS resolution advisory manuevre, there have to be two aircraft equipped with TCAS and S mode transponders. RA's can be issued against altitude reporting targets and with plain A mode there can only be traffic advisory. And if transponder is off (as it seems to be case in Brazil), TCAS is helpless.

Been in the TU Sim several times (other sim however) and talked to a lot of TU crews. All of them concurred that if a TCAS goes off they are not going to heed ATC commands but to follow TCAS no matter what. One put it brutally by saying "Why should I listen to the one who put me into a situation for the TCAS to go off in the first place?" While I find this a tad one sided, as a TCAS alert can be triggered by pilots mistakes as much as ATC mistakes, the gist of it is, when a TCAS goes off I'll follow it first and ask questions later.

Obviously the worst case scenario is if one guy follows TCAS and the other doesn't. So, if you get a TCAS RA and can't rely on the other guy to act on it, then things will go pearshaped very quickly.

I reckon that the Ueberlingen accident has brought that message home to just about all the TCAS users who care to read up on it. So let's hope that this will never ever happen again.

In fact, if one guy follows the TCAS and the other doesn't, you'd probably still be alright most of the time. It's when one follows it and the other _does_ take action, but the opposite action than they should, that things will go pear shaped.

On the TCAs issue : caution not to mix pre-Ueberlingen ( July 2002) ACAS training guidelines , with post Ueberlingen. The current ones are quite different.

At the time, the training guidelines were not that obvious : an RA was an " advisory" not a " command" to be followed with closed eyes regardless of anything else. The contradiction between an ATC clearance" against RA direction was not that clear.

Most AIPs ( including the German one that legally was in force at the time and place of the collision ) said that unless in Emergency pilots should not deviate from ATC clearances, and an RA was never defined as an emergency.
In our case the ATC instruction was BEFORE the RA. So a bit of kindness for our Russian colleagues.They did some things wrong perhaps, but so did everybody else that night. But all this is in the BFU report.

Back to the original thread :

Latest from the trial : 7 of the 8 defendants accused the late controller on duty as the only person responsible. . He turns out to be the perfect scapegoat .Even his colleague ( the one that went to bed at 2300 ) said it was all the other controller fault, as it was up to him to check what the technicians were doing and what were the consequences. The judge asked him " But why did not you ask them yourself ,as when you went off duty you saw all of them waiting to come in the OPS Room ? : his reply :" It was not my task, and even if I had asked them, I would not have been able to understand their responses , I am not a specialist "

Pathetic defense ...I do not know which lawyers are advising them, but I do not think this will impress the judges much.

as always...there was complete set of mistakes, but ultimately controller on duty cleared two planes on conflicting route to the same level. this tragedy is sad reminder for all of us professionals. and a lesson - they will always blame the last in the chain.

Only a couple of months ago, in spanish airspace, I heard another aircraft advise atc "tcas climb" and the controller came back and told him not to climb as he would go clear of the other traffic. If I hadn't heard it myself I wouldn't have believed it!:confused:

Kontrolor :
Not quite correct my friend, he did not clear them together . The 757 was cleared off route direct by Geneva, and the Tu154 cleared off route direct by Munich , on the strip he had them 7 minutes appart .When he discovered ( very late ) that they were in fact coming together , he cleared one down , not both... ( all this ,and more , on the BFU report ).

I do not agree with blaming the last one on the chain, wether it is a controller or a simple hand deck sailor ( Like the one that closed the door , also too late, of the "Herald of Free Entreprise ") because it does not solve anything, and confort the real responsibles in their views that since they have not been made responsible, there is nothing to change to prevent it from happening again.

Now the latest on the trial :
Tuesday the prosecutor made a strong requisition against the od Skyguide management, talking about " a negligent climate in the entreprise " he requested 15 months jail suspended sentence for the 3 top managers, 12 months for the maintenance head that authorised the systems to be switched off ,8 months for the other controller that went on break and 6 months for the 2 others accused .

It is still too early to say which way the Judge(s) will go.

I don't believe the official report made anything of both planes being on the same flight level. Why, like the GOL 73 and the Legacy, were they on the same FL in the first place and not at odd or even FLs according to which side of the north-south line they were heading?

Because they were both heading west?

Tim Dawson........Best comment so far
 

ATC Watcher
"the757 crew responded correctly (to TCAS) and the Tu154 did not"

Yes?

But you fail to say that:

757 crew responded incorrectly to ATC, while the TU154 responded correctly to ATC,
they were on the same frequency, weren't they?

This accident actually proves that almighty TCAS is not fail-safe at all.
You need one or both or more aircraft to obey TCAS command,
to get out of a collision
but if one of them starts dangerous direction descent or climb,
here you have it...

How did the 757 crew respond incorrectly to atc??

Green Guard, please tell me that you don't fly or control commercial air transport aircraft.......:eek:

Green Guard, please tell me WHAT the 75 crew did wrongly, with regard to ATC?
I regard TCAS as I do EGWPS. It's an automated system thats looking out for me. When it tells em to do something, it normally means failure to follow its instructions means you die. Period.
People miss things and get them wrong.
The ATC'er saw a conflict and kept trying to resolve it, long after he should have shut up.
The TU crew had a conflict, TCAS and ATC, and never resolved it.
THE 75 crew did everything they should have done and died.
ICAO must ensure that such an avoidable trgedy doesn't occur again. If you can't, or won't comply with TCAS RAs, THEN YOU SHOULDN'T BE IN CONTROLLED AIRSPACE.
Regardless of the faults with the ATC system that night, TCAS was the LAST safeguard. By choosing not to comply with the HARD RA, for whatever reason, then that safeguard was wilfully removed.
Apart the question of different languages on frequency TCAS is not only a lifesaver, it's also our best on board tool for Situational awareness. Some of our A320's have (had?) a software variant which wouldn't display TCAS targets if the range on the ND was over 40nm. On those aircfraft I never left the range over 40nm once I'd verified the next TO waypoint. Surely basic airmanship dictates that you look where you're going, using all the tools available to you.
I too, am very unhappy about any MEL alleviation that lets you operate without a fully serviceable TCAS system.

Hi all
just a short note regarding this painful case.
When investigating the LX498 crash (Zurich, 10Jan 2000) we travelled to Moscow, St Petersburg and Cisinau (Moldova) as the Captain was a Moldovan national and former (pre 1989) Aeroflot regional pilot.
Our knowledge of selection, training and operations in the FSU needed to be updated and documented.
This was an enriching and valuble experience which highlighted the professionalism of personnel, operations and proceedures in FSU and the use of Russian equipment.
However it also highlighted the different approach to HUFAC and its application. In particular a, then slightly 'old school', prevalent sceptiscism and mistrust of electronic in avionics. There was a very human oriented approach to most problems encountered in flight ops.
In particular TCAS was viewed as a gadget foisted upon Airlines and operators that (from Eastern European and beyond ops) seemed to be un-necessary. It was viewed with almost disgust and its challenge to human reasonning questionned!
We imagined the Uberlingen scenario where a pilot would listen to the human controller and not the TCAS command with its tragic consequences, and felt that this was a note-worthy point to raise with authorities in the west however it is/was one of those warnings lost in 'paper-space' and unheeded until proven correct....unfortunately in our own 'back garden' and not somewhere on the other side of the world!
This was 7 years ago and this attitude has probably died out now, and unfortunately with the 'watershed' accident in Uberlingen the point is made clearly regarding TCAS and its implications.
IMHO any one who still questions TCAS should rethink his/her position......on the ground, before joining the rest of us in an ever more crowded sky where we each survive thanks to each others (ATC included) professional dedication.
best regards
MB

Many pilots from the old East block countries were bought up in a much more rigid system of absolute obedience to instructions from the ground. If in doubt follow your training. At that time TCAS was still seen by many as riddled with faults ( Dallas Bump etc.) and as a non-revenue producing system not much time would be spent on instructing in it's use.

From an ATC point of view there was also initial resentment as it was seen by many as something that reduced our authority. Again, how much time was invested in training the actual controllers on the workings of the system From memory, most of the info we received came from ICAO posters and a campaign by EGATS (Merci, ATC Watcher) than from management. How much actual training did Peter Nielsen receive?

looks like the initial statements by management at the trial were a poor attempt at CYAS by muddying the waters

Pure speculation regarding this tragic case, but I was reliably informed a few years ago that to fly in certain parts of European airspace, A/C above a certain weight/seat allocation had to have TCAS fitted.

It was believed that some airlines fitted the kit to permit them to fly in said airspace, but did not train the crew in the correct use as that would have added more expense.

I am not in any way saying that this is what happened here - but in a regime whereby authority is everything and a way of life, it must be difficult, especially with regards to newish technology, to ignore commands/instructions given (in good faith) by an ATCO etc.

Fortunately, as Lon alludes to, Crews and ATCOs are now more aware of what should happen during a TCAS event.

Although a horrific incident, is a court case and possible prison sentence the best way to end this? Open reporting of incidents is what is needed - the threat of disciplinary action, either by company or courts, is not conducive to this.

Also, so many years have passed, and the ATCO involved is no longer with us - this leaves an instant and convenient scapegoat, which may mean that the truth, and indeed lessons to be learned, may never surface.

ACAS Training issues, Oh yes... that was and still is a problem.
A study made by SOFREAVIA in 2005 based on on board recordings from 4 European airlines ( 2 majors and 2 commuters ) over 4 years ( 2001-2004) showed that only 28% of the RAs were correctly followed by the pilots and in 10% of the cases the pilots choose not to follow the RAs or acted opposite to it. Althought the percentages might be better today, seen the incidents reports we read, there is still a lot of room for improvement, and not only in Russia...

Frangible :
I forgot to mention that to read the BfU report you must have a bit of aviation knowledge. It was not made for journalists or the common layman.
Green Guard : you said : Please expand : I do not know what you are trying to say.
Back to te trial :
Yesterday was Defense day :
Not surprisingly the defense lawyers put all the blame on the controller on duty, to prove that the management they defend was not responsible.
One said " The controller created himself the problem . he committed many large errors and contrary to what the prosecution said , he was not overworked or stressed "
Another quote " he made himself responsible for the severe faults he made which ultimately led to the catastrophe "
Another lawyer said : The telephone was not a factor , he should have put the Airbus A320 on hold while solving the telephone problem "
I always like when lawyers are telling us how we should have done our job, Afterwards of course.....

ATC vs TCAS
 

Quote:
"757 crew responded incorrectly to ATC "

because ATC never asked that crew to descend. It was TCAS that made them to descend.

It is easy to give statements from in front of our computers. But on every day of our duty we always follow ATC instructions (whether we are from West or East), and any TCAS TA makes us see the picture, before RA comes out. We can all swear to act exactly like the 757 crew did. But in the heat of moment or a pressure, TA, RA and in the same time LOUD command from ATC, to start and expedite descend they did what they did.

And 757 crew did everything correct regarding TCAS and died.

We all need even love TCAS. "I can see you on my TCAS"

Main question here is how this tragedy could have been avoided. We all know one answer:
If both parties responded correctly to TCAS and incorrectly to ATC.
Second answer may be about new TCAS perhaps.

Oh nonsense.

To follow a TCAS RA in the absence of any ATC instruction at all is nothing like an incorrect response to an ATC instruction. Hell, to follow a TCAS RA which is exactly the opposite of an ATC instruction is exactly the right thing to do! We've all agreed (us controllers and you pilots) that a TCAS RA supersedes an ATC instruction. Therefore, the 75 crew did what we all depended upon them to do, and the TU crew did not. Think of it this way, a TCAS RA is the ultimate ATC instruction. It trumps all others. For crying out loud, it erases the ATC instruction. How can you respond incorrectly to an ATC instruction that has been erased? We ATCers support that idea. To echo BEagle, PLEASE tell me that you don't fly or control transport aircraft...

Where the hell is Jerricho when you need him?:ugh:

And Nubboy...
Actually, until we all have some technology in place that tells us you guys are getting an RA, we're not going to be shutting up. That's because we have no way of knowing whether or not you're getting the RA up there or not, and we're accustomed to trying to resolve the situation as long as there is an opportunity to do so. So I beg you, ignore me. Tune me out. Follow the RA. But know I'll keep chattering...

-Dave

Green Guard, I'm all for intelligent debate, but you're coming out with complete and utter garbage proving that you know pi$$ all about which you are talking about. You make my blood boil :mad:

Cheers
Dave
I fully take your point about not knowing if wehave an RA or not.
Isn't the technology there to broadcast/receive teh TCAS instructions so that at least you could be shouting in harmony with machines instead of against, as was so painfully the case here? Just a thoughtfor the techies.
As for Greenguard..........thank God I'm part time which reduces, statistically, the chance of ever having you on any side of a frequency I might be using.

I reckon most posters are forgetting the whole point of this thread - it's about a court case and not about the facts as they see them.

Yes, the SOP's will be gone over and may be criticised along with the actions of the pilots but I believe the overiding factor here is once you have agreement on the regulation of the skies in that we have ATC - it's their ultimate responsiblity to prevent collisions - no matter why or how - the guy in charge at the time will be blamed.

On top of that we have the additional National interests and affronts of "we wouldn't do that kind of thing here" and "how dare you insult us," plus and increasing lobby of folk who seem bent on indicting company directors at every turn to further some kind of vendetta against corporate business.

757 crew never stated that they are in TCAS descend.

and as far as same level - both aircraft were cleared to FL360. so he should have put more attention to them.

but generaly - I'm working in relatively small ACC unit, but nobody would allow such degradation of service without backup. I think Zurich controllers accepted what the managment threw at them and result was a tragedy.

and I'm not blaming the atco, I just wanted to emphesase, that he had a responsibility and he failed to use all the resorces he had in order to prevent the collision (ultimately).

Chances are they had no say in the matter !!

:mad: