Airbus crash/training flight
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Clandestino
Habsheim accident was not power related,
Regards,
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Clandestino,
I agree with most of what you said, however, since we are on the topic:
According to the report, the overflight was planned and briefed as follows:
Whether or not they were aware of alpha-floor inhibition below 100ft agl is irrelevant, because, elaborating on point 4) above, ...
... they had disabled it anyway.
Note 1: The described procedure disables all autothrust functionality until a reset on the ground.
Although Alpha-Floor protection is a function of the autothrust system, it engages at high angles of attack approaching alpha-max, regardless of the prior autothrust state (disarmed, armed, engaged). Thus autothrust cannot be disarmed (as opposed to disabled) in such a way that alpha-floor protection is inhibited. It must be disabled to inhibit this protection.
Note 2:Concerning the unexpectedly long time the engines took to spool up, the report concludes that TOGA thrust application was planned from a thrust setting required for a slow, prolonged low-level flyby at alpha-max, i. e. a high power setting, from which maximum thrust would have been available very quickly.
Instead the engines had to spool up from idle. According to the FCOM I have seen it should have been in "Apprach Idle", which is a raised idle setting to allow faster acceleration to TOGA thrust, but this may have been introduced later than 1988, and it may still have taken several seconds to spool up.)
Bernd
I agree with most of what you said, however, since we are on the topic:
[...] flying at around 30 ft RA, with engines at idle, waiting for alpha-floor too kick in [...]
Originally Posted by Habsheim investigation report, section 2.2.3, p. 50
1) at 100ft
2) with flaps in position 3 and landing gear extended
3) in level flight decelerating to maximum angle of attack [...]
4) after disengagement of automatic go-around protection [...] (alpha-floor)
[...]
7) with go-around initiated by the first officer
2) with flaps in position 3 and landing gear extended
3) in level flight decelerating to maximum angle of attack [...]
4) after disengagement of automatic go-around protection [...] (alpha-floor)
[...]
7) with go-around initiated by the first officer
Originally Posted by Habsheim investigation report, section 2.2.3, p. 52
4) [...]
The inhibition in this case can only be achieved in practice by pressing and holding the two switches placed on the throttles. After 30 seconds, inhibition becomes permanent for the rest of the flight.
The inhibition in this case can only be achieved in practice by pressing and holding the two switches placed on the throttles. After 30 seconds, inhibition becomes permanent for the rest of the flight.
Note 1: The described procedure disables all autothrust functionality until a reset on the ground.
Although Alpha-Floor protection is a function of the autothrust system, it engages at high angles of attack approaching alpha-max, regardless of the prior autothrust state (disarmed, armed, engaged). Thus autothrust cannot be disarmed (as opposed to disabled) in such a way that alpha-floor protection is inhibited. It must be disabled to inhibit this protection.
Note 2:Concerning the unexpectedly long time the engines took to spool up, the report concludes that TOGA thrust application was planned from a thrust setting required for a slow, prolonged low-level flyby at alpha-max, i. e. a high power setting, from which maximum thrust would have been available very quickly.
Instead the engines had to spool up from idle. According to the FCOM I have seen it should have been in "Apprach Idle", which is a raised idle setting to allow faster acceleration to TOGA thrust, but this may have been introduced later than 1988, and it may still have taken several seconds to spool up.)
Bernd
Jofm5 - no intent to take the thread off topic and re-open the Habsheim issue - I was just pointing out that the accident occurred as indicated and that those who once again leap all over Airbus because it is Airbus have much to learn. The posting of this information (the graph) has nothing to do with the Perpignan accident and shouldn't be accepted as anything more than an attempt to foreshorten any discussion about stolen/falsified DFDRs. We need to let the events unfold and for some to stop painting devils on the wall.
I have my own theories of why this accident occurred but will hold onto them for now and wait for the DFDR and, what may be more important in this case, the CVR.
Clandestino;
Berndt's post handles these points very well.
PJ2
I have my own theories of why this accident occurred but will hold onto them for now and wait for the DFDR and, what may be more important in this case, the CVR.
Clandestino;
And despite rumors to the contrary, A/THR was not disabled but merely disconnected.
PJ2
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By the time they realised that there was no automatic TOGA forthcoming and manually selected it, it was too late. And despite rumors to the contrary, A/THR was not disabled but merely disconnected.
Dream Land;
The "Alpha prot" mode of the 320 is, of course, beyond the control of the crew but it is automatically disabled below 100' RA.
The decision was made by Captain Asselin to do the fly-past above 100' so he elected to permanently (for that flight only - it re-engages but only after the next landing), disengage the a/thr so it would not "spoil" a high angle of attack, gear-down, low-speed fly-past demonstration by engaging.
The fly-past was actually flown at and below 30' ostensibly because the grass strip was so narrow and so short that height perception made the field "smaller" and so they flew lower. Cockpit planning and discipline issues arise here but we won't be distracted from your question. When it became rapidly apparent to the First Officer first, that they were below the trees, Asseline "firewalled" (to TOGA) the thrust levers and the N1's, which were at about 29% or IDLE thrust, took the expected six to eight seconds to accelerate. They almost made it - another second or so and the airplane would have skimmed the treetops and the engines would have not have swallowed as much foliage. Academic though it may be, to some extent the fbw (yaw damper) kept the aircraft relatively straight as it descended through the trees.
That is the extent of the "intervention" with the autothrust and was never a "computer problem" as so many claim.
The "Alpha prot" mode of the 320 is, of course, beyond the control of the crew but it is automatically disabled below 100' RA.
The decision was made by Captain Asselin to do the fly-past above 100' so he elected to permanently (for that flight only - it re-engages but only after the next landing), disengage the a/thr so it would not "spoil" a high angle of attack, gear-down, low-speed fly-past demonstration by engaging.
The fly-past was actually flown at and below 30' ostensibly because the grass strip was so narrow and so short that height perception made the field "smaller" and so they flew lower. Cockpit planning and discipline issues arise here but we won't be distracted from your question. When it became rapidly apparent to the First Officer first, that they were below the trees, Asseline "firewalled" (to TOGA) the thrust levers and the N1's, which were at about 29% or IDLE thrust, took the expected six to eight seconds to accelerate. They almost made it - another second or so and the airplane would have skimmed the treetops and the engines would have not have swallowed as much foliage. Academic though it may be, to some extent the fbw (yaw damper) kept the aircraft relatively straight as it descended through the trees.
That is the extent of the "intervention" with the autothrust and was never a "computer problem" as so many claim.
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just a SUPOSITION
What happens if the aircraft being repainted, somebody puts adhesive tape on the static ports and nobody removes or spots the tapes before take-off on the flight test day...
Anybody remembering what happened on the Aéropéru 757 in a similar situation?
Indicated air speed lower than real, protection kicking in at the wrong time (stick shaker, pusher....)??? Any Airbus specialist to comment on these please?
Anybody remembering what happened on the Aéropéru 757 in a similar situation?
Indicated air speed lower than real, protection kicking in at the wrong time (stick shaker, pusher....)??? Any Airbus specialist to comment on these please?
Warning Toxic!
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Can Habsheim be discussed on another thread? It bears no relation to this incident, and all Habsheim matters are completely irrelevant. I was banned from this thread for a week, and look how out of control it has got!
I just want to come to this thread to read up on the latest news, not go through a discussion of some totally unconnected incident from umpteen years ago! What is going on?
I just want to come to this thread to read up on the latest news, not go through a discussion of some totally unconnected incident from umpteen years ago! What is going on?
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I find myself agreeing with Rainboe and would like The Habshiem subject dropped from this thread. I also find it hard to understand why things that I found out three weeks after the Habshiem accident are still being talked about years after the event as if it was new news.
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AH! But is it not the obfuscation of news with irrelevance that makes PPRune special? 
It is of concern to me how quickly a thread on a tragic loss of life can be dragged into the mire.
It is of concern to me how quickly a thread on a tragic loss of life can be dragged into the mire.
Last edited by BOAC; 6th Dec 2008 at 15:16.
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A simple and practical question.
The NTSB has an e-mail service, which personally I appreciate and find relevant.
Does the BEA have a similar service ? I haven't found one, but I may have been looking in the wrong place.
CJ
The NTSB has an e-mail service, which personally I appreciate and find relevant.
Does the BEA have a similar service ? I haven't found one, but I may have been looking in the wrong place.
CJ
The NZ media is openly discussing the compensation that the families of the perished Air New Zealand employees are believed to receive. Also, as the aircraft was officially operated by XL Airways Germany, they - or their insurance company - have agreed to compensate Air New Zealand for the value of the aircraft.
Aircrash: compo for families in new territory - Sunday Star-Times - National News
Aircrash: compo for families in new territory - Sunday Star-Times - National News
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I'm also with Rainboe about Habsheim from a technical point of view.
BUT at pprune are obviously serious concerns about accident investigation on french territory and AIRBUS involved. And dear mods, you can delete this post as many others about this concern (for whatever reason...), but it will NOT help to regain trust to BEA.
Cheers
BUT at pprune are obviously serious concerns about accident investigation on french territory and AIRBUS involved. And dear mods, you can delete this post as many others about this concern (for whatever reason...), but it will NOT help to regain trust to BEA.
Cheers
Back to the original thread...will the entire structure be recovered and reassembled for analysis?We have heard very little about what exactly has been taking place in the waters off Perpignan.
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tubby,
There is very little more news....
Which is mostly what prompted my question about a 'BEA e-mail service', actually....
The fact that there ARE people who feel directly concerned, and would like to keep track of the investigation, even if not being part of it, does not really seem to have sunk in.
CJ
There is very little more news....
Which is mostly what prompted my question about a 'BEA e-mail service', actually....
The fact that there ARE people who feel directly concerned, and would like to keep track of the investigation, even if not being part of it, does not really seem to have sunk in.
CJ
A reasonable summing up?
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press.co.nz - Get the latest local, national and world news from Christchurch's daily newspaper
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The wreck, or whatever is left, is at about 40m, so recovery will be slow and difficult.
I guess salvation won't be a big problem.
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Hi ChristiaanJ
I think this link is what you can use to contact the French BEA:
Bienvenue sur le site du Bureau d'Enquêtes et d'Analyses
Appart from that, good to see most people here have more hindsight than in France , and do not agree with the fancy theories about Habsheim.
I think this link is what you can use to contact the French BEA:
Bienvenue sur le site du Bureau d'Enquêtes et d'Analyses
Appart from that, good to see most people here have more hindsight than in France , and do not agree with the fancy theories about Habsheim.