Sky-crashGuide report released

[crashskyguide]

Check out www.bfu-web.de for the report on the 757/Tupolev collision over Germany in 2002.
It's available in English.

Full report in English at: www.bfu-web.de/berichte/02_ax001efr.pdf

[Panman]

Makes for solemn reading.

It was difficult for me reading that the crew of the 757 were alive after impact. How awful it must be to sit there with an out of control aircraft.

[RatherBeFlying]

Safety Recommendation No. 08/2004

To enhance the performance of ACAS ICAO should initiate the development of down-linking RAs to ATC, using such technologies as SSR Mode S and Automatic Dependent Surveillance -Broadcast (ADS-B).

Among a number of straightforward recommendations, this one will let ATC know when not to interfere with a TCAS RA.

[Don't Look Now]

With all due respect, RatherbeFlying, ATC have never had the right to "interfere" with TCAS, full stop.
In this particular instant the controller working that night did not "interfere" with the TCAS RA, but rather used the information available to him ie a mode C readout which was several seconds behind the actual vertical movement of the aircraft in question.
Most controllers in the world know that TCAS has priority over their commands. I, as a controller, am happy to work with the backup of TCAS, as I know that its' information is faster and more accurate than my radar processed and therefore delayed representation.
The BFU reccomendation would be another link in the safety chain to avoid further incidents.
It will be interesting if this reccomendation will be pursued by national and especially cash-strapped privatised Air Navigation Service Providers!

[Smoketoomuch]

The 2 tables of TCAS data on p57 make very sombre reading.
Hard to believe that a few columns of numbers can be so depressing.

[RatherBeFlying]

23 second delay from RA to notifying ATC

Don't Look Now -- As we have sadly seen, cockpit workload and other radio calls can delay a crew notifying ATC of an RA.

If the controller had had the RA notification on his scope, I'm sure he would have used the information appropriately.

[NigelOnDraft]

If the controller had had the RA notification on his scope, I'm sure he would have used the information appropriately

Partially disagree with what you are syaing... Given the completely unacceptable level of Management at this ACC, and the maintenance that was going on, most "electronic gizmos" developed over the years had been turned off. It is more than likely that if such a RA notification system had been developed, it would not have been available.

I am not disagreeing with such a system being developed. But lets keep uppermost this hard hitting report's findings. Technology did not really fail. Management, Quality Control and Safety Systems totally did...

NoD

[RDUBWI]

RA Downlink

Lots of intersting reading on this subject on Eurocontrol website;
www.eurocontrol.int/ra-downlink

Eurocontrol guys had an interesting presentation at the IFATCA conference in Hong Kong last March. Seems like most of RA are not reported or reported incorrectly or reports are delayed, so maybe (?) RA downlink is the answer.

[airship]

I spent an hour reading through the report. Probably a very silly question, but why did the ATCO contact the TU154M first and instruct them to descend, as opposed to contacting the B757-200 and instructing them to descend? I only ask this with regard to "Right of Way" and the point that it would normally be the aircraft (the B757-200 in this case) approaching from the other aircraft's left who should take avoiding action. Does an ATCO bear that in mind when deciding which aircraft to contact in order to maintain separation?

(The Rules of the road at sea are similar, except for the vertical separation...?!)

[ferris]

Airship.
No. Once a situation has deteriorated to the point of avoiding action- and remember, controllers are aiming to keep separation standards, in this case 7nm- you are just grabbing for the first straw you can. The report notes that the solution attempted wouldn't have maintained a sep standard anyway, even if there had been no RA.
I remember reading somewhere that the ATCO in question made the decision to descend the TU154 because it would have had to change level in the near future anyway, as it was about to change course? I can't recall the source so cannot say if that is correct.
If there is adequate planning ie. you had seen the conflict early, you think about things like who is landing first, who has right of way etc. Every controller does this sort of decision process hundreds of times a day. Sep decisions are not supposed to be arse-plucks. The holes lined up in this case.

Don't look now.
The crux of that issue is not IF ATC should interfere with RAs, but how can ATCs AVOID interefering if we don't know pilots are reacting to them? The fastest way for a controller to resolve a conflict is vertically. It's very difficult not to go for vertical if things are getting tight. It's a natural reaction. And (as seen here) it could be the worst thing to do. The situation as it stands is less than ideal.

[airship]

ferris,

Once a situation has deteriorated to the point of avoiding action- and remember, controllers are aiming to keep separation standards, in this case 7nm- you are just grabbing for the first straw you can.

In an emergency, pilots are trained to follow pre-determined procedures. What perturbs me is your use of the phrase "you are just grabbing for the first straw you can" with regard to the ATCO. Do you mean that no pre-determined procedures exist to cover this type of event? The report doesn't go into why the ATCO contacted the TU154M first instead of the B757-200. Under the circumstances, if the ATCO had contacted the B757-200 first and instructed them to descend, the outcome would have been just a drama as opposed to a crisis with lethal consequences...

[VectorLine]

airship

Do you mean that no pre-determined procedures exist to cover this type of event?

Well, no. The event happened when procedures broke down. When you realise you have made a mistake and it looks like 2 aircraft are going to collide, there is absolutely no time or rational brain process available to go through a checklist.

A loose parallel would be this.
Say you are walking along the street, looking at a map and look up to find yourself about to bump into someone doing the same.

The other person looks up at the same time and you both instinctively turn to miss each other. What procedure do you go through to decide which way to turn?

More often than not, both people turn into each other, then both take correcting action and turn the other way into each other again. Most often, you will somehow miss. Occaisionally you bump into one another.

OK, very simplified. However I think it is a good example of the "OH F K! " response when you realise the mistake and your sphincter starts twitching.

[Whipping Boy's SATCO]

I'm sorry but I think some of us are missing the point here. It is my understanding that TCAS is the LAST line of defence, designed to cater for a plethora of failings that have already conspired against the aircrew involved. Having read the report it seems to me that the real issue here is the less that satisfactory guidance that the TU 154 crew were given regarding the use of TCAS and some rather interesting CRM aspects. Undoubtedly, the ATC hierarchy had more holes that the proverbial Swiss Cheese (no pun intended). However, ultimately, if all aircrew had followed the TCAS indications and ignored ATC (as is their right), we wouldn't have been having this conversation.

[ShooTheGap]

It was the right call as per his flight plan. what surprises me after reading the report is how with a seperation of 7nm on a scope displaying 80 nm he omits to pass essential traffic to the DHL. that would have been basic procedure. And then after observing the mode C indicating descent he leaves that scope and attends to the arrival on a different scope...Wow!
It is also scary reading the list of equipement that was U/S that night.
Having said that, may his soul and that of all of the victims of this tragedy R.I.P.

[airship]

VectorLine, I understand what you are saying by the use your "parallels". But an ATCO is supposedly in a position to be controlling the quoted pedestrians, not be one of them. And you are missing the point I was trying to draw attention to. Pilots are trained to incorporate certain fundamental priorities in an emergency. Like flying the airplane. By your account, once an ATCO needs to say "OH F K!", he has no pre-determined options because he has not been trained to follow any fundamental procedures. I repeat here my earlier reflection that "Under the circumstances, if the ATCO had contacted the B757-200 first and instructed them to descend, the outcome would have been just a drama as opposed to a crisis with lethal consequences..." The ATCO could have contacted either aircraft and both aircraft were at high altitude, so why not follow the straight-forward rule of "Right of Way" on which to base a response?

Whipping Boy's SATCO, TCAS is obviously still not fully implemented and tomorrow, another ATCO could give opposite instructions to a RA. Unless ATC is in a position to receive the same TCAS messages as the aircraft they are directing. For the present, clear rules obliging aircraft to give TCAS precedence must be reinforced. Otherwise, dramas will continue to become crises...whether or not there is someone in "the tower".

[Whipping Boy's SATCO]

airship, I think we agree.

[airship]

Whipping Boy's SATCO, yes and I too agree that we are in agreement. Is that enough for a quorum?

[GearDown&Locked]

I'm sorry to intrude here, on such a serious matter, but I can't understand WHY the TU-154 crew didn't comply with the RA.
I'm wondering how confortable would feel an aircrew, any aircrew, to disregard an RA, and do precisely the opposite?

Does it come down to a matter of what/who to trust the most? Do pilots trust TCAS? If so, in a similar conflict situation they will comply with the RA info, no matter what ATC says, simply because they trust the system; But if they don't trust the system, there is space for doubt in their minds, and probably will follow an opposite command from the ATC.

Are pilots instructed to obey TCAS over ATC? What should an ATCO do when a pilot reports back (if he/she has the time for it!) "Can't comply - we have an RA saying otherwise" ?

Excuse me for posing so many questions.

GD&L

[BOAC]

GD&L - your question is answered in the report. Read it all - it is a painful, harrowing exercise, but worth it. SOPs for those carriers have, I believe, now changed.

[RDUBWI]

Why 350 for Tu154?

Airship,
The answer to your question is on page 38 of the report:

"The control strip for the TU154M shows the intended routing NEGRA-Trasadingen (TRA) – BENOT. The estimated times of passing the listed waypoints were indicated with 21:36 hrs,
21:42 hrs and 21:51 hrs. Following the passing of Trasadingen VOR (TRA) a descent to FL350 was planned because the AIP Switzerland states that odd level numbers are to be used for the
intended flight route."