LH 747 missed Mexicana A 320
Pegase Driver
Lost luggage ; there is no standard radar return time. this depends on what kind of radar you operate . the rotation of the antenna will determine the range. In en-route operations , you need range . the majority of the radars have a 6 rpm or 10 seconds update. that will give you roughly 300 NM . In approach ops , where you need less range but need a faster refresher rate , you go to 10 rpm and have a 6 sec return rate.
In the case of Zurich, the referesher rate was 12 seconds.
In the case of Zurich, the referesher rate was 12 seconds.
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MEX terminal area is regarded as difficult, for good reason.
terrain, weather, atc, approach design, airspace congestion, lack of adequate infrastructure etc.
On the other hand, radar coverage is pretty advanced and air traffic controllers in general are good and particularly considerate to foreign carriers. Helicopters use their own visual corridors and remain below 500 ft.
Mexican professional pilots are most aware of this circumstances, as we fly in and out of mmmx every day.
Advice? trust your controller and limit your v/s 1000ft prior to level-off. If this should fail to do the trick, trust and follow your ra´s.
Mexicana de aviación pilots are proud to share Star Alliance with LH and our other partners. We earned our place there, unlike other people who are nowadays "flying for other peoples". Maybe there's a standard after all.
Mateo six: please share with us all those cover-up stories you have cracked!
I'd wait for some intelligent info on this near-miss incident.
if I have it fist i´ll let you know.
rooster
terrain, weather, atc, approach design, airspace congestion, lack of adequate infrastructure etc.
On the other hand, radar coverage is pretty advanced and air traffic controllers in general are good and particularly considerate to foreign carriers. Helicopters use their own visual corridors and remain below 500 ft.
Mexican professional pilots are most aware of this circumstances, as we fly in and out of mmmx every day.
Advice? trust your controller and limit your v/s 1000ft prior to level-off. If this should fail to do the trick, trust and follow your ra´s.
Mexicana de aviación pilots are proud to share Star Alliance with LH and our other partners. We earned our place there, unlike other people who are nowadays "flying for other peoples". Maybe there's a standard after all.
Mateo six: please share with us all those cover-up stories you have cracked!
I'd wait for some intelligent info on this near-miss incident.
if I have it fist i´ll let you know.
rooster
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Sr. gallo:
The standard in “Compania Mexicana de Aviación” is that primarily of nepotism and dangerous machismo. A little intro:
Poor general knowledge of aircraft, procedures and ops,
f/a practicing (you know!),
Looking at most new-hires after 97/98 I don’t think that there’s a standard after all: Mostly under-qualified new pilots (entry tests are much easier when daddy’s got access to them, etc.)
I think MX earned its place in our typical Mexican wey…
Proud? Of what? Certainly not safety…
Email me, I will not say more here.
Too bad I don’t really exist any more, I should be Otumba now...
Salu2
The standard in “Compania Mexicana de Aviación” is that primarily of nepotism and dangerous machismo. A little intro:
Poor general knowledge of aircraft, procedures and ops,
f/a practicing (you know!),
Looking at most new-hires after 97/98 I don’t think that there’s a standard after all: Mostly under-qualified new pilots (entry tests are much easier when daddy’s got access to them, etc.)
I think MX earned its place in our typical Mexican wey…
Proud? Of what? Certainly not safety…
Email me, I will not say more here.
Too bad I don’t really exist any more, I should be Otumba now...
Salu2
Last edited by MateoSix; 30th Oct 2002 at 01:49.
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Another incident involving TCAS and a loss of separation took place in Canada on 13 July 2001.
The Transportation Safety Board of Canada recently released its final report (A01C0155) and made this finding: "Risk of collision was increased because TCAS and air traffic control are not coordinated. Each flight crew independently decided to disregard the TCAS resolution advisory commands because they were contradictory to instructions the controller had already issued."
The report also said that "On 27 September 2002, Transportation Safety Board sent an Aviation Safety Advisory (615-A020026) to Transport Canada suggesting that they may wish to review current regulations and TCAS guidance material with a view toward developing clear procedures to prevent a risk of collision in the event of conflict between ATC instructions and TCAS RA commands."
This conflict between TCAS commands and ATC instructions is also addressed in FAA Advisory Circular 120-55B which is available in PDF format at this link: FAA AC 120-55B - Air Carrier Operational Approval and Use of TCAS II
Bottom line? TCAS is the final line of defense. Follow your RA!
The Transportation Safety Board of Canada recently released its final report (A01C0155) and made this finding: "Risk of collision was increased because TCAS and air traffic control are not coordinated. Each flight crew independently decided to disregard the TCAS resolution advisory commands because they were contradictory to instructions the controller had already issued."
The report also said that "On 27 September 2002, Transportation Safety Board sent an Aviation Safety Advisory (615-A020026) to Transport Canada suggesting that they may wish to review current regulations and TCAS guidance material with a view toward developing clear procedures to prevent a risk of collision in the event of conflict between ATC instructions and TCAS RA commands."
This conflict between TCAS commands and ATC instructions is also addressed in FAA Advisory Circular 120-55B which is available in PDF format at this link: FAA AC 120-55B - Air Carrier Operational Approval and Use of TCAS II
Bottom line? TCAS is the final line of defense. Follow your RA!
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suggesting that they may wish to review current regulations and TCAS guidance material with a view toward developing clear procedures to prevent a risk of collision in the event of conflict between ATC instructions and TCAS RA commands
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A few thoughts have crossed my mind about this thread ...
It seems that some pilots who posted their remarks know more than they are allowed to say, some obviously being rather bitter it seems ...
One thing that catches my attention is that this incident is being investigated because of Lufthansa 's request. From the report of Der Spiegel one gets the impression that neither Mexican ATC nor Mexicana seemed to be bothered by this and did not report it to the responsible authority to be further investigated. If this is true then ...
A question for ATC Watcher or other controllers:
If there is a "near-miss" in your airspace or a flight crew follows their TCAS RA, are you (as an air traffic controller) required to submit a report?
Captain 104 :
Will the final report be officially published by Lufthansa or the LBA?
7 7 7 7
It seems that some pilots who posted their remarks know more than they are allowed to say, some obviously being rather bitter it seems ...
One thing that catches my attention is that this incident is being investigated because of Lufthansa 's request. From the report of Der Spiegel one gets the impression that neither Mexican ATC nor Mexicana seemed to be bothered by this and did not report it to the responsible authority to be further investigated. If this is true then ...
A question for ATC Watcher or other controllers:
If there is a "near-miss" in your airspace or a flight crew follows their TCAS RA, are you (as an air traffic controller) required to submit a report?
Captain 104 :
Will the final report be officially published by Lufthansa or the LBA?
7 7 7 7
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what happens with mode s
Correct me if I'm wrong but I thought that mode s was supposed to send the data up and down the link. I'd sort of assumed that the ATC rad would show an TA/RA indication through that?
Maybe mode s is not as widely used as I thought?
Maybe mode s is not as widely used as I thought?
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Hello SQUAWk7777
To answer your question:
1)LBA( or BFU) I don't know.
2)DLH safety department CF definitely yes(cockpit crew info only).
Just my guess.
Some facts:
CF published the incident for internal info to cockpit crews in the briefing room in FRA some days after it happened.
I never did and never will publish internal info from a company in PPRuNe. For nearly 2 weeks nothing in the media.
On 24th Oct. the german magazine DER STERN published a breathtaking version( pilot pulled rapidly....). That is the magazine which published Hitlers falsified diary years ago and not very trustworthy.
AIR SAFETY NET followed in moderate style and in english.
2 days later the magazine DER SPIEGEL published a version so
close to facts and the official LH report that one could think they are very well informed.
There is room for speculation:
Since LH for sure considered the incident as serious as we would expect ( why should they send their experts to MEX?) and at the same time mexican authorities kept more than quiet: could it be that someone tickled the press to overcome mexican resistance to mention or even talk about it?
Amazing: still today no one talking or writing about an incident which is to be classified according to my information as serious and for sure more than a "non-event".
To answer your question:
1)LBA( or BFU) I don't know.
2)DLH safety department CF definitely yes(cockpit crew info only).
Just my guess.
Some facts:
CF published the incident for internal info to cockpit crews in the briefing room in FRA some days after it happened.
I never did and never will publish internal info from a company in PPRuNe. For nearly 2 weeks nothing in the media.
On 24th Oct. the german magazine DER STERN published a breathtaking version( pilot pulled rapidly....). That is the magazine which published Hitlers falsified diary years ago and not very trustworthy.
AIR SAFETY NET followed in moderate style and in english.
2 days later the magazine DER SPIEGEL published a version so
close to facts and the official LH report that one could think they are very well informed.
There is room for speculation:
Since LH for sure considered the incident as serious as we would expect ( why should they send their experts to MEX?) and at the same time mexican authorities kept more than quiet: could it be that someone tickled the press to overcome mexican resistance to mention or even talk about it?
Amazing: still today no one talking or writing about an incident which is to be classified according to my information as serious and for sure more than a "non-event".
Last edited by Captain104; 7th Nov 2002 at 19:34.
Pegase Driver
in reply to questions :
7777 : an airprox filed by a crew will of course be logged by ATC and investigated by the authorities responsible for ATS at the time the incident occurred. So if an airprox has been filed by either DLH or MEX, an investigation will be made and a report will be made . That report will be sent to the safety dept of the airline(s) involved and the ATC facility involved . That is what the (ICAO) book says. Some States (e.g UK) go further and really make public SOME of the airprox investigations reports.
I doubt very much that Mexico Civil aviation authority will do so ( but I might be wrong )
A TCAS RA deviation will only be logged if it interferd with ATC or is abnormal in nature ( like the many RAs caused by ghost tragets for instance ) Some States ( or Eurocontrol in Europe ) have special forms for this that are centralised and investigated ( Bretigny is doing this for Eurocontrol member states for instance )
A TCAS RA that results in a loss of separation will not necessarily result in an airprox being filed , especilally if the "error" is made by one of the crews ( e.g over-reaction to an RA , a very frequent case ) as an airprox can only be filed by aircrew.
ATC should in that case log the loss of separation on the TCAS report and on their logs. What happens further depends on the safety culture of the place. Again the UK and the USA for instance have firm procedures for this, but they are the very minority unfortunately.
Not knowing what really happenned in Mexico, the above is only generic info of course.
Quack driver : It is quite complex but the quick answer would be : Mode s transponders broadcast altitude that are picked up by TCAS. They do not broadcast RAs to be picked up by the ground. From a world wide perspective , very few ATC centres have acess to mode S or use Mode S. Of those only a couples ( e.g Miami in the US or Maastricht in Europe ) have a data link receiving capability. TCAS RAs ( or Altitude ) is not (yet) part of the grounds receivers capabilites.
Capt 104 : Since you seem to have access to the original DLH/CF data , can you check that the DLH crew stayed within RA max deviation ( i.e max 400ft from asigned Alt ) if they did not that could explain the sequence of events and the controller reaction )
7777 : an airprox filed by a crew will of course be logged by ATC and investigated by the authorities responsible for ATS at the time the incident occurred. So if an airprox has been filed by either DLH or MEX, an investigation will be made and a report will be made . That report will be sent to the safety dept of the airline(s) involved and the ATC facility involved . That is what the (ICAO) book says. Some States (e.g UK) go further and really make public SOME of the airprox investigations reports.
I doubt very much that Mexico Civil aviation authority will do so ( but I might be wrong )
A TCAS RA deviation will only be logged if it interferd with ATC or is abnormal in nature ( like the many RAs caused by ghost tragets for instance ) Some States ( or Eurocontrol in Europe ) have special forms for this that are centralised and investigated ( Bretigny is doing this for Eurocontrol member states for instance )
A TCAS RA that results in a loss of separation will not necessarily result in an airprox being filed , especilally if the "error" is made by one of the crews ( e.g over-reaction to an RA , a very frequent case ) as an airprox can only be filed by aircrew.
ATC should in that case log the loss of separation on the TCAS report and on their logs. What happens further depends on the safety culture of the place. Again the UK and the USA for instance have firm procedures for this, but they are the very minority unfortunately.
Not knowing what really happenned in Mexico, the above is only generic info of course.
Quack driver : It is quite complex but the quick answer would be : Mode s transponders broadcast altitude that are picked up by TCAS. They do not broadcast RAs to be picked up by the ground. From a world wide perspective , very few ATC centres have acess to mode S or use Mode S. Of those only a couples ( e.g Miami in the US or Maastricht in Europe ) have a data link receiving capability. TCAS RAs ( or Altitude ) is not (yet) part of the grounds receivers capabilites.
Capt 104 : Since you seem to have access to the original DLH/CF data , can you check that the DLH crew stayed within RA max deviation ( i.e max 400ft from asigned Alt ) if they did not that could explain the sequence of events and the controller reaction )
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Follow up
Found this today in an official Bulletin on the BFU-website:
http://www.bfu-web.de/Bulletin/Bulletin0210.PDF on page 6 only in german.
The reason I would like to revive this thread is to quote the mexican duty supervisor: "IN THE APPROACH SECTOR OF MEX DO NOT FOLLOW TCAS COMMANDS." Nice statement and worth some discussion.
Try to translate highlights:
On flight FRA to MEX 7th Oct. 2002 occured a dangerous airprox. On board of B747-400 were 388 PAX and 19 crew.
Planned was an ILS DME #2 for RWY 05R i.e. approach via VOR PACHUCA (PCA) to LUCIA(SLM) and than MATEO(SMO) with a left turn to ILS 05R. Due to TS returns on WX radar between MATEO and Mexico City, LH Cpt. asked for direct course to MEX VOR and than an ILS DME #1 approach to avoid thunderstorms. Controller refused request, so they continued to MATEO. Controller ordered step descends to 13000', than to 12000' and finally to 11000'. Just prior reaching MATEO passing 11800' the crew noticed an AC on TCAS left in 10 o'clock position about 600' lower approaching rapidly. TCAS indication changed quickly from white to yellow with TA "traffic traffic." Immediately followed a RA (resolution advisory) "climb climb." FO as pilot flying reacted immediately and initiated a climb. The flight path of both AC crossed. According
to LH cockpit crew the vertical distance was about 100'.
The Cpt. called MEX approach and reported "TCAS climb". The controller answered "negativ climb, hold altitude due traffic". He repeated this 2 times than said "continue approach." On request of ATC the approach was discontinued. The AC was now send to OTUMBA first, than to MEX VOR to enter the hold. The LH crew indicated their decreasing fuel reserves and and received a clearance for an uneventful approach and landing.
After landing the crew had a conversation with the "Duty Supervisor" of MEX ATC. He declared that a mexican AB 320 on another frequency had received a descend clearence to 11000' and a left turn to MATEO VOR. The mexican Airbus followed this command very slow, which caused the airprox. The LH crew followed the TCAS RA contradictory to orders of ATC.
According to the mexican "Duty Supervisor" in the approach sector to MEX there is a rule:"DO NOT FOLLOW TCAS COMMANDS."
..................
The evaluation of CVR indicated that RT communication around MEX was mainly handled in spanish language. Only foreign AC were handled in english. At the time of the incident the frequency was quite busy........
The ATC tape with communication between A 320 and controllers is not available.... CVR or FDR of mexican A 320 is not available to BFU.
Please excuse my goofy pidgin english. What do you think?
http://www.bfu-web.de/Bulletin/Bulletin0210.PDF on page 6 only in german.
The reason I would like to revive this thread is to quote the mexican duty supervisor: "IN THE APPROACH SECTOR OF MEX DO NOT FOLLOW TCAS COMMANDS." Nice statement and worth some discussion.
Try to translate highlights:
On flight FRA to MEX 7th Oct. 2002 occured a dangerous airprox. On board of B747-400 were 388 PAX and 19 crew.
Planned was an ILS DME #2 for RWY 05R i.e. approach via VOR PACHUCA (PCA) to LUCIA(SLM) and than MATEO(SMO) with a left turn to ILS 05R. Due to TS returns on WX radar between MATEO and Mexico City, LH Cpt. asked for direct course to MEX VOR and than an ILS DME #1 approach to avoid thunderstorms. Controller refused request, so they continued to MATEO. Controller ordered step descends to 13000', than to 12000' and finally to 11000'. Just prior reaching MATEO passing 11800' the crew noticed an AC on TCAS left in 10 o'clock position about 600' lower approaching rapidly. TCAS indication changed quickly from white to yellow with TA "traffic traffic." Immediately followed a RA (resolution advisory) "climb climb." FO as pilot flying reacted immediately and initiated a climb. The flight path of both AC crossed. According
to LH cockpit crew the vertical distance was about 100'.
The Cpt. called MEX approach and reported "TCAS climb". The controller answered "negativ climb, hold altitude due traffic". He repeated this 2 times than said "continue approach." On request of ATC the approach was discontinued. The AC was now send to OTUMBA first, than to MEX VOR to enter the hold. The LH crew indicated their decreasing fuel reserves and and received a clearance for an uneventful approach and landing.
After landing the crew had a conversation with the "Duty Supervisor" of MEX ATC. He declared that a mexican AB 320 on another frequency had received a descend clearence to 11000' and a left turn to MATEO VOR. The mexican Airbus followed this command very slow, which caused the airprox. The LH crew followed the TCAS RA contradictory to orders of ATC.
According to the mexican "Duty Supervisor" in the approach sector to MEX there is a rule:"DO NOT FOLLOW TCAS COMMANDS."
..................
The evaluation of CVR indicated that RT communication around MEX was mainly handled in spanish language. Only foreign AC were handled in english. At the time of the incident the frequency was quite busy........
The ATC tape with communication between A 320 and controllers is not available.... CVR or FDR of mexican A 320 is not available to BFU.
Please excuse my goofy pidgin english. What do you think?
Last edited by Captain104; 9th Jan 2003 at 12:45.
Pegase Driver
Capt 104 ; the BFU unfortunately only reports the facts as reported by the DLH crew + data collected on the 747.
The Mexicans have another story, but not official yet, so difficult to argue their case .
I hesitate to post their version on the net .
Let's say that the interesting points to be looking for would be :
Did the MEX A320 received a heading and did not comply ?
Was the rate of decent of the A320 in excess of 4000 ft/min ?
Did the MEX A320 had its TCAs on ?
Was the actual minimum lateral distance in excess of 2NM ?
Was the 3rd aircrfat involved 1000ft above the 747 and what was his transponder ?
Was the holding full due Cbs over the field ?
From what I read, and if it is confirmed officially, the R/T reaction of the controller could be well justified.
But I find the remark of the Mexican ATC supervisor astonishing . I guess (hope ) some language / communication problems might be at the source of that statement.
As to the R/T, well in Mexico spanish is the official R/T language.
in any case the A320 was in another frequency, so the 747 would not have heard the original clearance, and should it had, and it had been in English, it would not have meant much to the 747 anyway.
The Mexicans have another story, but not official yet, so difficult to argue their case .
I hesitate to post their version on the net .
Let's say that the interesting points to be looking for would be :
Did the MEX A320 received a heading and did not comply ?
Was the rate of decent of the A320 in excess of 4000 ft/min ?
Did the MEX A320 had its TCAs on ?
Was the actual minimum lateral distance in excess of 2NM ?
Was the 3rd aircrfat involved 1000ft above the 747 and what was his transponder ?
Was the holding full due Cbs over the field ?
From what I read, and if it is confirmed officially, the R/T reaction of the controller could be well justified.
But I find the remark of the Mexican ATC supervisor astonishing . I guess (hope ) some language / communication problems might be at the source of that statement.
As to the R/T, well in Mexico spanish is the official R/T language.
in any case the A320 was in another frequency, so the 747 would not have heard the original clearance, and should it had, and it had been in English, it would not have meant much to the 747 anyway.
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Something's lost in the translation (both of them).
Gentlemen,
What an un believable statement! If this person meant to say what is translated here, then he has put himself in an indefensible position. What for?
Cap 104:
I flew all over Mexico for 4 years and I can tell you that I NEVER EVER heard of any such rule. Just the thought of it is ridiculous.
Mexico follows ICAO's procedures and if a report of a Nearmiss was filed by Lufthansa I'm sure The DGAC (Mexico's CAA) will have to come up with a response and carry out an investigation of their own. It may take longer than it would in Germany that's for sure.
In all Mexican Operator's training and operating cultures TCAS RA's are perfectly understood. If the situation had been reversed, the Mexicana would have followed his RA too.
You should go back a little bit on this thread and read The Rooster's post.
Since the statement has been translated from Spanish to German and on this thread onto English, I have to think that something got lost...
ATC Watcher claims to know the Mexican version...What's with all the secrecy?
According to the Mexican "Duty Supervisor" in the approach sector to MEX there is a rule: "DO NOT FOLLOW TCAS COMMANDS"
Cap 104:
I flew all over Mexico for 4 years and I can tell you that I NEVER EVER heard of any such rule. Just the thought of it is ridiculous.
Mexico follows ICAO's procedures and if a report of a Nearmiss was filed by Lufthansa I'm sure The DGAC (Mexico's CAA) will have to come up with a response and carry out an investigation of their own. It may take longer than it would in Germany that's for sure.
In all Mexican Operator's training and operating cultures TCAS RA's are perfectly understood. If the situation had been reversed, the Mexicana would have followed his RA too.
You should go back a little bit on this thread and read The Rooster's post.
Since the statement has been translated from Spanish to German and on this thread onto English, I have to think that something got lost...
ATC Watcher claims to know the Mexican version...What's with all the secrecy?
No translation here
"Do not follow TCAS commands" is not a translation.
While the report is written in German, this quote is given in English on page 6. My surmise is that the conversation with the ATC Duty Manager was conducted in English.
While the report is written in German, this quote is given in English on page 6. My surmise is that the conversation with the ATC Duty Manager was conducted in English.
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ATC watcher:
Fully agree with your questions concerning A 320 involved. Have still no access to any statement by mexican officials but it seems that language problems refering to the duty managers statement
are not likely. If there is a "mexican version" of the story I would enjoy any enlightment.
Did not talk to the crew myself but I have information that the conversation between crew and duty manager was conducted in plain clear english.
As RatherBeFlying states the quote "do not follow TCAS commands"( in the approach sector to MEX) is original and as I understand varified by the BFU.
Thank you for your replies.
Regards
Fully agree with your questions concerning A 320 involved. Have still no access to any statement by mexican officials but it seems that language problems refering to the duty managers statement
are not likely. If there is a "mexican version" of the story I would enjoy any enlightment.
Did not talk to the crew myself but I have information that the conversation between crew and duty manager was conducted in plain clear english.
As RatherBeFlying states the quote "do not follow TCAS commands"( in the approach sector to MEX) is original and as I understand varified by the BFU.
Thank you for your replies.
Regards
Last edited by Captain104; 9th Jan 2003 at 08:50.
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Could this not be a reference to switching from 'TA/RA' to 'TA only' in some busy terminal areas?
When I used to fly into Orlando Sanford on the 767 the brief for the airport was to switch to 'TA only' due to the intense light a/c traffic in the area, often on a parallel runway.
Similar reason why QRH for engine failure calls for 'TA only' on the TCAS, as an RA may lead to more problems than it solves when overloaded with targets.
Does anyone know the maximum number of resolutions current TCAS systems can resolve at anyone time?
When I used to fly into Orlando Sanford on the 767 the brief for the airport was to switch to 'TA only' due to the intense light a/c traffic in the area, often on a parallel runway.
Similar reason why QRH for engine failure calls for 'TA only' on the TCAS, as an RA may lead to more problems than it solves when overloaded with targets.
Does anyone know the maximum number of resolutions current TCAS systems can resolve at anyone time?