Mid-Air Collision over Southern Germany (merged)
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ATC in there...
Condolences to all involved. Totally tragic. 
From the news it appears that the Russian plane started the descent at the same time the DHL plane was descending due to TCAS. I am reserved in saying this as my only source is the media (not the most accurate in accident reports)...
Can someone confirm this ?
A few other questions, excuse the ignorance. I am not trying to second-guess the ATCs involved in this but, could they have not given the DHL a higher flight-level after the first couple of calls to the Russian plane ? What are the limitations of even a fully loaded 757 concerning max FL ? Or would it have just taken too long ? What about a turn ?
Also a couple of questions concerning procedures. Usually how long before a handover is the second ATC alerted ? Is it usual practice for an ATC to request from the previous ATC to give the plane an instruction before it is handed over ?
Again, excuse my ignorance, and I am not second guessing people, just questions that came up in my mind after having heard of this...
From the news it appears that the Russian plane started the descent at the same time the DHL plane was descending due to TCAS. I am reserved in saying this as my only source is the media (not the most accurate in accident reports)...
Can someone confirm this ?
A few other questions, excuse the ignorance. I am not trying to second-guess the ATCs involved in this but, could they have not given the DHL a higher flight-level after the first couple of calls to the Russian plane ? What are the limitations of even a fully loaded 757 concerning max FL ? Or would it have just taken too long ? What about a turn ?
Also a couple of questions concerning procedures. Usually how long before a handover is the second ATC alerted ? Is it usual practice for an ATC to request from the previous ATC to give the plane an instruction before it is handed over ?
Again, excuse my ignorance, and I am not second guessing people, just questions that came up in my mind after having heard of this...
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Contrary to various statements here, I have seen great improvements in the quality of Russian pilots over the last 4 or 5 years. In fact, I would have more confidence in a positive response to avoiding action from certain Russian airlines than from the sub continental airlines and/or some of the big Europeans who tend to reply with "was that meant for me?"!!!
The reluctance of some pilots to appropriately respond to avioding action has already been discussed at length here
- I wonder if this will make some of you think differently about your response in future.
This is not meant to antagonize / inflame the discussion but the link should be obvious.
Condolences to all involved and my colleague in Zurich.
The reluctance of some pilots to appropriately respond to avioding action has already been discussed at length here
- I wonder if this will make some of you think differently about your response in future.
This is not meant to antagonize / inflame the discussion but the link should be obvious.
Condolences to all involved and my colleague in Zurich.
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Condolences to all involved.
Stating the obvious, clearly, the 2 aircraft were flying at the same altitude without lateral seperation. Isn't it about time we took steps to ensure both lateral and vertical deconfliction outside of terminal airspace.
With modern GPS equipped aircraft every time we go flying we go either directly over or under other traffic; the big sky principle no longer applies.
Last time I checked, airways were 10 nm wide, why don't regulators require all operators to offset 1 mile right (or even 100m) in the cruise phase to reduce the chances of this unfortunate accident re-occuring. Even in RVSM airspace, there is sufficient space to allow this principle to be applied until the aircraft begins descent.
It might appear that I am trying to bolt the stable door after the horse has bolted but how many of you guys out there have had the same thought when you have had a min-sep 1000' below another aircraft with 16 miles/ minute of closure.
Again condolences to the families,
Ghost
Stating the obvious, clearly, the 2 aircraft were flying at the same altitude without lateral seperation. Isn't it about time we took steps to ensure both lateral and vertical deconfliction outside of terminal airspace.
With modern GPS equipped aircraft every time we go flying we go either directly over or under other traffic; the big sky principle no longer applies.
Last time I checked, airways were 10 nm wide, why don't regulators require all operators to offset 1 mile right (or even 100m) in the cruise phase to reduce the chances of this unfortunate accident re-occuring. Even in RVSM airspace, there is sufficient space to allow this principle to be applied until the aircraft begins descent.
It might appear that I am trying to bolt the stable door after the horse has bolted but how many of you guys out there have had the same thought when you have had a min-sep 1000' below another aircraft with 16 miles/ minute of closure.
Again condolences to the families,
Ghost
Last edited by Ghostflyer; 2nd Jul 2002 at 09:45.
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Swiss ATC media conference just held
Today’s mid-air collision over Southern Germany is, according to Skyguide (the Swiss ATC), the result of simultaneously initiated descents by both the aircraft that eventually collided. In the case of the Russian Tupolev TU-154, the descent was initiated based on ATC instructions, whereas the descent of the B-757 freighter was triggered by its TCAS.
Anton Maag, Chief of Zurich-Kloten Control Tower, and Skyguide Spokesman Patrick Herr, held a press conference today, Tuesday, to review the events of the previous night.
Between 2300 and 2400, there were no unusual occurences in Swiss air control space, with only a few aircraft in the air. Swiss ATC was handed over the Russian TU-154, which was on a East-to-West routing by German ATC at around 2330, whilst the B-757 freighter, on a South-to-North routing, was handed over by Italian ATC to Swiss ATC at 2323. Both planes were at an altitude of 36000 feet (around 11500 meters).
The Swiss controller thus advised the Russian aircraft to descend to a lower flight level. According to Skyguide’s Anton Maag, it required three attempts before this advice was confirmed by the Russian crew. As a result, the Russian aircraft began its descent very late. At the same time, the crew of the B-757 freighter was advised for reasons unclear by its TCAS to descend as well. Obviously, according to Maag, this command has to be followed immediately.
The eventual collison happened at an altitude of 35000 feet between 2335 and 2336. Both aircraft remained visible for a number of sweeps on the radar screen. Maag says there were no linguistic problems between the Swiss controller and the Russian crew, whilst Herr mentioned two “sticking points” in the context of this crash. “First, why did the Russian pilot not react immediately? Second, why did the TCAS on board the B-757 advise its crew to dive?” So apart from the question as to why the TCAS on board the B-757 did not recognize the other aircraft's descent, both aircraft were tuned to the same radio frequency, so they could both simultaneously hear their respective interaction with Zurich-Kloten tower.
Above compiled based on Swiss media reports available online.
Anton Maag, Chief of Zurich-Kloten Control Tower, and Skyguide Spokesman Patrick Herr, held a press conference today, Tuesday, to review the events of the previous night.
Between 2300 and 2400, there were no unusual occurences in Swiss air control space, with only a few aircraft in the air. Swiss ATC was handed over the Russian TU-154, which was on a East-to-West routing by German ATC at around 2330, whilst the B-757 freighter, on a South-to-North routing, was handed over by Italian ATC to Swiss ATC at 2323. Both planes were at an altitude of 36000 feet (around 11500 meters).
The Swiss controller thus advised the Russian aircraft to descend to a lower flight level. According to Skyguide’s Anton Maag, it required three attempts before this advice was confirmed by the Russian crew. As a result, the Russian aircraft began its descent very late. At the same time, the crew of the B-757 freighter was advised for reasons unclear by its TCAS to descend as well. Obviously, according to Maag, this command has to be followed immediately.
The eventual collison happened at an altitude of 35000 feet between 2335 and 2336. Both aircraft remained visible for a number of sweeps on the radar screen. Maag says there were no linguistic problems between the Swiss controller and the Russian crew, whilst Herr mentioned two “sticking points” in the context of this crash. “First, why did the Russian pilot not react immediately? Second, why did the TCAS on board the B-757 advise its crew to dive?” So apart from the question as to why the TCAS on board the B-757 did not recognize the other aircraft's descent, both aircraft were tuned to the same radio frequency, so they could both simultaneously hear their respective interaction with Zurich-Kloten tower.
Above compiled based on Swiss media reports available online.
Last edited by Alpha Leader; 2nd Jul 2002 at 10:13.
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This is indeed a tragic accident, and but for the grace of God could have taken many, many more lives. I don’t presume to make any conclusions about this event, but there are a number of issues that we should think about in busy European RVSM airspace.
It is entirely possible that at least one of the aircraft involved in this did all of these things. It is tragic in the extreme. I offer these pointers not to criticise or suggest possible cause, but to reinforce good airmanship and operating practice.
Sincere condolences, and my deepest sympathy to the controller at Swiss.
- Respond to TCAS resolution advisories in the extent to which the cues are provided on your EADI or EVSI. An RA will often require no more than 1500 fpm climb or descent to deconflict the traffic. At high Mach numbers and flown manually, the pitch change is remarkably small. A panic large input may cause additional problems or even an upset.
- Resist the temptation, especially at night, to try and second guess the TCAS RA. In RVSM, and aircraft 1000 feet below you might look as if it’s actually above and vice versa. Trust the TCAS and use it to enhance your mental model of your bit of airspace. You may think you’ve worked out the best avoidance, but the TCAS has a contract with the conflicting traffic and has worked out the best avoidance manoeuvre. Remember, the other target may be simultaneously involved in avoiding another aircraft.
- If your aircraft is fitted with an early type of display, remember that the azimuthal error in TCAS can be up to 20, which means that the intruder could be either left of the nose or right of the nose. TCAS is designed to provide only vertical deconfliction, so again don’t try to second guess it.
- Listen out on your frequency, try and plot other aircraft in your mental model, and think about where conflicts might arise. If necessary inform ATC of any concerns you have about another aircraft. They will be more than happy to put your mind at rest.
- Make sure that at least one of you is monitoring 121.5 at all times. Someone may have urgent news for you, and you may not be talking to them at the time
It is entirely possible that at least one of the aircraft involved in this did all of these things. It is tragic in the extreme. I offer these pointers not to criticise or suggest possible cause, but to reinforce good airmanship and operating practice.
Sincere condolences, and my deepest sympathy to the controller at Swiss.
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sincere condolences to the families
Were the pilots english speaking.If they were not it is possible that the translator for some reason was not in the flight deck when the atc called.
Just thinking aloud.
Were the pilots english speaking.If they were not it is possible that the translator for some reason was not in the flight deck when the atc called.
Just thinking aloud.
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Dealing with numerous Russion/Ukraine registered and operated aircraft here on a daily basis from An-12's right up to the big daddy An225 and every variety of Tupalov, Yak and Ilyushian, I can honostly say the aircrew are some of the most courteous and accomodating pilots we work with, far more so than quite a few of the western/sub continent/Asian and local operaters we deal with. The english and general operations have improved dramatically over the last few years. I will be the first to admit that it is important that sometimes extra effort is required to ensure the correct information has been absorbed but then this does not just apply to them.
It is far to early to make any reasonable conclusion on what has happened here and it is important to realize how many variables are to be addressed, including Comms, ATC Handover/Takeover procedures, ambiguous ATC instructions and mis-understandings, there is even possibility of an in-flight situation on the Tupalov that inhibited an immediate response.....and the list can go on.
Additionally my fear is that amongst Aircrew and ATC alike, to much emphasis and reliance is being placed on the TCAS system and on a daily basis the call "its OK I have him on TCAS" or more so the fact that pilots are trying to separate themselves or continually harass ATC about TCAS traffic that is under ATC control (especially on the climb or descent), is causing many a misunderstanding and unnessary RTF clutter.
Let all the facts be gathered, make no more speculation based on the typically innacurate and sensationalized media reporting and all will be revealed.
Regardless of who is at fault, there have been peoples lives destroyed, families destroyed and life long reputations to consider. Lets just show compassion at his stage and let the authorities sort the facts out. This is a trajedy for all of the world's aviatian community.
It is far to early to make any reasonable conclusion on what has happened here and it is important to realize how many variables are to be addressed, including Comms, ATC Handover/Takeover procedures, ambiguous ATC instructions and mis-understandings, there is even possibility of an in-flight situation on the Tupalov that inhibited an immediate response.....and the list can go on.
Additionally my fear is that amongst Aircrew and ATC alike, to much emphasis and reliance is being placed on the TCAS system and on a daily basis the call "its OK I have him on TCAS" or more so the fact that pilots are trying to separate themselves or continually harass ATC about TCAS traffic that is under ATC control (especially on the climb or descent), is causing many a misunderstanding and unnessary RTF clutter.
Let all the facts be gathered, make no more speculation based on the typically innacurate and sensationalized media reporting and all will be revealed.
Regardless of who is at fault, there have been peoples lives destroyed, families destroyed and life long reputations to consider. Lets just show compassion at his stage and let the authorities sort the facts out. This is a trajedy for all of the world's aviatian community.
Last edited by Fox3snapshot; 2nd Jul 2002 at 10:50.
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TCAS in trouble
Thank you Alpha leader for keeping us posted on the latest info on this tragic event...
Without trying to draw any premature conclusions, it seems to me the Skyguide Spokesman, Patrick Herr is correctly focusing ATC investigation line on those two "sticky points".
R.I.P. for the innocent Souls on board....
Without trying to draw any premature conclusions, it seems to me the Skyguide Spokesman, Patrick Herr is correctly focusing ATC investigation line on those two "sticky points".
R.I.P. for the innocent Souls on board....
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Fox3snapshot,
My sentiments exactly. As I said earlier, Russian R/T has improved dramatically over the last 4 or 5 years. The obvious questions now seem to be - 1. was avoiding action given 2. If not, why not 3. If yes, why was a collision not avoided? I don't want to pre-empt the investigation but these questions need to be answered.
Again, Condolences to all.
My sentiments exactly. As I said earlier, Russian R/T has improved dramatically over the last 4 or 5 years. The obvious questions now seem to be - 1. was avoiding action given 2. If not, why not 3. If yes, why was a collision not avoided? I don't want to pre-empt the investigation but these questions need to be answered.
Again, Condolences to all.
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Anyone had a TCAS RA "reversal"; ie "Descend, Descend" turn into "Climb, Climb now!"? I've had it in training but not on the line (fortunately).
Again, all is speculation at the moment. All we can do right now is feel symapthy for all those involved.
Again, all is speculation at the moment. All we can do right now is feel symapthy for all those involved.
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questions..questions...
yes, Guy these questions pop up to mind but other factors should be also under consideration:
1. how busy was the sector?
2. R/T freq. congestion (or condition)
3. russian pilot's english level
...these are (inter alia) some questions that pop up in mind....
Answers should be very carefully joined together so that correct conclusions are drawn and put to prastice ASAP to avoid similar situations in future (here I speak as a front line radar ATCO)...
1. how busy was the sector?
2. R/T freq. congestion (or condition)
3. russian pilot's english level
...these are (inter alia) some questions that pop up in mind....
Answers should be very carefully joined together so that correct conclusions are drawn and put to prastice ASAP to avoid similar situations in future (here I speak as a front line radar ATCO)...
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If (a big if!) it is the case that the DHL aicraft initiated descent in response to the TCAS information (and possible ATC traffic info) and the Tupolov after eventually receiving his descent instructions (Swiss controllers apparantly gave 3 calls) commenced his descent, the concern I have for TCAS confusiuon mentioned previously has been realized. Latest reports (from a Swiss ATC source) also inidicate that the aircrew on the Tupolov were having no problems understanding or speaking english.
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NilNoted
Yes it was the Australian registered B757, not an English registered one. A9C DHL formerly OODLK formerly VH AWE. I knew both pilots of the 757 and my heart felt condolences go out to their family and all their friends who are no doubt suffering beyond belief at this most tragic time, as am I. Obviously condolences also to the family and friends of the TU154.
Another point which troubled me somewhat was the release of the crew's name in the media before family had been informed, how this can be allowed to happen is mind boggling to me.
Yes it was the Australian registered B757, not an English registered one. A9C DHL formerly OODLK formerly VH AWE. I knew both pilots of the 757 and my heart felt condolences go out to their family and all their friends who are no doubt suffering beyond belief at this most tragic time, as am I. Obviously condolences also to the family and friends of the TU154.
Another point which troubled me somewhat was the release of the crew's name in the media before family had been informed, how this can be allowed to happen is mind boggling to me.
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Another question. If the controller had no respose from the russian a/c, why had HE not instructed the 757 to climb? If the TU154 had not started its descent when the 757s TCAS initiated there is no reason for TCAS to tell the 757 to go up rather than down, by the time the reversal would have come in it was probably to late.
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Germany Crash: DHL's publicity
Aviation-bitten media worker as I am:
15 hours after the Überlingen crash, it is interesting to see how the media tide is geared against the Russian counterpart of the accident, even though there are strong indications that a TCAS malfunction/misinterpretation or slow Swiss ATC response may have contributed to the crash as well.
This is, however, only informed backstage talk. Watching the Big International TV channels the only thing we see is Tupolev wreckage, Aeroflot-heritage stories, background on a remote Bashkirian aviation enterprise. Where is DHL ? Background on their ops ? Incident records ? The pilots personal records ? Bahraini aviation authorities' followup capabilities on safety - the plane was on reg there ? And where is the whole 757 for that matter ?
It appears it's easier to sell TV commercials to a worldwide courier chain than to the flag carrier of an autonomous forgotten Russian republic, and to organize your reporting accordingly.
Is it me that is being cynical ? Or them ?
Jan-Erik Andelin EFHK
15 hours after the Überlingen crash, it is interesting to see how the media tide is geared against the Russian counterpart of the accident, even though there are strong indications that a TCAS malfunction/misinterpretation or slow Swiss ATC response may have contributed to the crash as well.
This is, however, only informed backstage talk. Watching the Big International TV channels the only thing we see is Tupolev wreckage, Aeroflot-heritage stories, background on a remote Bashkirian aviation enterprise. Where is DHL ? Background on their ops ? Incident records ? The pilots personal records ? Bahraini aviation authorities' followup capabilities on safety - the plane was on reg there ? And where is the whole 757 for that matter ?
It appears it's easier to sell TV commercials to a worldwide courier chain than to the flag carrier of an autonomous forgotten Russian republic, and to organize your reporting accordingly.
Is it me that is being cynical ? Or them ?
Jan-Erik Andelin EFHK
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Hi foxmoth,
Without knowing the displacement of the traffic, the amount of traffic and frequency conjestion etc. it impossible to guess, there may have been traffic above the 757 which precluded a climb.
Without knowing the displacement of the traffic, the amount of traffic and frequency conjestion etc. it impossible to guess, there may have been traffic above the 757 which precluded a climb.
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More comprehensive insight by Swiss ATC
From a release by Swiss news agency SDA at 1306 today:
By belatedly obeying ATC instructions to decrease altitude, the crew of the TU-154 set off the TCAS of the B-757 freighter approaching at same flight level, which caused the Boeing’s pilot to dive, too. This is the immediate cause of this collision, and the air traffic controllers on duty are – for the time being at least – free of blame.
According to Anton Maag, Manager of Skyguide’s Area Control Centre, speaking at a media conference held on Tuesday morning at Zurich Airport, the situation until immediately prior to the mid-air collision had been entirely normal. Given the time of night, few aircraft were in the sky.
One of those up there was the TU-154 operated by Bashkirian Airlines on a charter flight from Moscow to Barcelona via Munich and Geneva. Flying from south to north towards Brussels at the same time there was a B-757 freighter of DHL. Both aircraft were at 36000 feet. Their flight paths were to cross at Ueberlingen – a routine event.
For this crossing, the controller at Zurich ATC wanted the Russian aircraft to descent to a lower flight level, as there was going to be a scheduled landing at Geneva anyway. Between 8 and 10 nm (or approx. 1 ½ minutes of flight time) prior to the crossing point ATC instructed the TU-154 crew to initiate a descent – but this instruction was not confirmed. A second identical advice also remained unacknowledged. It was only on the third attempt that the TU-154 crew reacted and began to seek the assigned, lower flight level.
In the meantime, the TCAS on board the B-757 had registered the approaching TU-154 at the same flight level and instructed its pilot to descend. According to generally accepted international practice, TCAS warnings and instructions are adhered to immediately and without clearance from ATC, according to Anton Maag. Between 2335 and 2336 hrs the two aircraft collided at 35300 ft.
According to Anton Maag, the timing of the first set instructions to the TU-154 crew to descend was not ideal, but would have sufficed “under normal circumstances”. And Skyguide spokesman Patrick Herr insists that the type of instruction and the timing of the upcoming crossing of flight paths were going entirely to SOP.
The two “sticking points” that the investigation would have to concentrate on were, according to Patrick Herr
1) Why did the Russian crew not react immediately to the first set of instructions issued to them by ATC?
2) And why did the TCAS on board the B-757 instruct its crew to descend?
There were apparently no language problems whatsoever. According to Anton Maag, the preceding conversations with either flight deck had been entirely normal. The Russian pilot, says Bashkirian Airlines, was 52 years old and had some 10 years of experience behind him. The controller on duty, according to Patrick Herr, also has many years of experience on the job.
The TU-154 approaching from the east had been handed over by German ATC to its Swiss counterpart (which is responsible for that particular sector despite its location above German territory) at 2330. The flight had been advised in a timely fashion, too. The B-757 freighter had crossed the Italian-Swiss border (to the south of the collision site) at around 2300.
At the time of the actual collision, there was very light air traffic, with only a few aircraft in the sky. The two controllers on duty in Zurich had only one sector to look after.
Thanks for your appreciation, atc_ring
By belatedly obeying ATC instructions to decrease altitude, the crew of the TU-154 set off the TCAS of the B-757 freighter approaching at same flight level, which caused the Boeing’s pilot to dive, too. This is the immediate cause of this collision, and the air traffic controllers on duty are – for the time being at least – free of blame.
According to Anton Maag, Manager of Skyguide’s Area Control Centre, speaking at a media conference held on Tuesday morning at Zurich Airport, the situation until immediately prior to the mid-air collision had been entirely normal. Given the time of night, few aircraft were in the sky.
One of those up there was the TU-154 operated by Bashkirian Airlines on a charter flight from Moscow to Barcelona via Munich and Geneva. Flying from south to north towards Brussels at the same time there was a B-757 freighter of DHL. Both aircraft were at 36000 feet. Their flight paths were to cross at Ueberlingen – a routine event.
For this crossing, the controller at Zurich ATC wanted the Russian aircraft to descent to a lower flight level, as there was going to be a scheduled landing at Geneva anyway. Between 8 and 10 nm (or approx. 1 ½ minutes of flight time) prior to the crossing point ATC instructed the TU-154 crew to initiate a descent – but this instruction was not confirmed. A second identical advice also remained unacknowledged. It was only on the third attempt that the TU-154 crew reacted and began to seek the assigned, lower flight level.
In the meantime, the TCAS on board the B-757 had registered the approaching TU-154 at the same flight level and instructed its pilot to descend. According to generally accepted international practice, TCAS warnings and instructions are adhered to immediately and without clearance from ATC, according to Anton Maag. Between 2335 and 2336 hrs the two aircraft collided at 35300 ft.
According to Anton Maag, the timing of the first set instructions to the TU-154 crew to descend was not ideal, but would have sufficed “under normal circumstances”. And Skyguide spokesman Patrick Herr insists that the type of instruction and the timing of the upcoming crossing of flight paths were going entirely to SOP.
The two “sticking points” that the investigation would have to concentrate on were, according to Patrick Herr
1) Why did the Russian crew not react immediately to the first set of instructions issued to them by ATC?
2) And why did the TCAS on board the B-757 instruct its crew to descend?
There were apparently no language problems whatsoever. According to Anton Maag, the preceding conversations with either flight deck had been entirely normal. The Russian pilot, says Bashkirian Airlines, was 52 years old and had some 10 years of experience behind him. The controller on duty, according to Patrick Herr, also has many years of experience on the job.
The TU-154 approaching from the east had been handed over by German ATC to its Swiss counterpart (which is responsible for that particular sector despite its location above German territory) at 2330. The flight had been advised in a timely fashion, too. The B-757 freighter had crossed the Italian-Swiss border (to the south of the collision site) at around 2300.
At the time of the actual collision, there was very light air traffic, with only a few aircraft in the sky. The two controllers on duty in Zurich had only one sector to look after.
Thanks for your appreciation, atc_ring
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I am not going to speculate on the reasons for this terrible crash as I and none of us know all of the facts.
With regard to TCAS, there are many many traffic conflicts that occur that would otherwise have resulted in a possible collision. Instead of complete devastation all that happens in the majority of cases is a bit of extra paperwork at the end of a flight. As long as there are at least 2 aircraft in the same region of airspace there will always be a very small risk of collision, particularly when only 1 has TCAS, but TCAS is something I would not leave base without particularly as the skies become more and more congested. Should TCAS be partly to blame for this accident it's benefits far outweigh it's flaws.
ES
With regard to TCAS, there are many many traffic conflicts that occur that would otherwise have resulted in a possible collision. Instead of complete devastation all that happens in the majority of cases is a bit of extra paperwork at the end of a flight. As long as there are at least 2 aircraft in the same region of airspace there will always be a very small risk of collision, particularly when only 1 has TCAS, but TCAS is something I would not leave base without particularly as the skies become more and more congested. Should TCAS be partly to blame for this accident it's benefits far outweigh it's flaws.
ES