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Concorde crash: Continental Airlines cleared by France court

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Concorde crash: Continental Airlines cleared by France court

Old 19th Dec 2012, 00:36
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Hi jcjeant,

The little exercise I made just above gives me the opportunity to use its data for a follow-on about that discussion we had some pages ago:
Originally Posted by AlphaZuluRomeo
Originally Posted by jcjeant
I really have no difficulty to imagine the strip being swept along the trajectory of the aircraft, as its 200 tons rolled over it... but it seems that notion eludes some people anyway.
Yes I have really difficulty to imagine the strip being swept along the trajectory (over such a large distance) of the aircraft ...
It is a concept that escapes me completely .. seems some"magic" at work there ..
What is the definition of "such a large distance" for you?
I'm fond of Harry Potter, but not so fond of magic regarding aviation safety.
Please, see this pic I made by adding things to the Annex 12 from final report.

Let's compare to the testimonies:
- Firefigther #1 said "black smoke" (tyre) around S6;
- Firefigther #2 said "black smoke" (tyre) around S5, then small fire;
- Firefigther #3 said small fire around S5, then big fire;
- Captain @ E5 (near the firefighters building) said fire begun at +/- 100m around W7.

I consider Firefigther #1 probably made a mistake between S6 & S5, because 'his' location (S6) is consistent neither with the other testimonies, neither with the material evidences.

Hence we can write:
1,500 m -> S5 TWY, the strip lay around there before Concorde rolled over it;
1,642 m -> first parts found from the water deflector, from slab 139 and onwards;
1,740 m -> the titanium strip finally lay there, at slab 152, along with a big part of tyre (transversally cut);
1,820 m -> the unburnt kerozen mark at slab 163;
1,860 m -> the first traces of soot (hence: big fire);
1,950 m -> the other 'fitting' part of the transversally cut tyre at slab 180;

=> The strip "travelled" ~240 m in the wake of Concorde and/or being for a moment stuck into the tyre.
=> Such a distance really doesn't feel 'magic' to me. Nor 'such a large distance', considering the forces involved.
=> The provided pic also shows that there is no inexplicable discrepency between the firefighters/captain testimonies and the events reported by the BEA, contrary to what some lawyers and/or TV shows would have us believe.

Last edited by Jetdriver; 19th Dec 2012 at 14:58.
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Old 19th Dec 2012, 00:41
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Lyman (nee Bearfoil)

Your credibility and our sanity would be massively enhanced if after all these years and thousands of posts you could demonstrate the ability to learn and make use of the rudimentary tool for block quoting others.
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Old 19th Dec 2012, 00:44
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Originally Posted by Lyman
The runway pictures that show carbon deposition are aerial, long distance, no?
Honestly? No. That's not what I see.

Originally Posted by Lyman
I think the report compelling, but it is too loose, and presumes things that are not shown, nor discussed, imho....
That's your opinion indeed, I acknowledge that but don't agree.
I have the advantage of being perfectly able to read French, hence I have access to the (rich) appendix 6 which was never translated to English (AFAIK).
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Old 19th Dec 2012, 07:53
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I have offered possible approaches to glean some understanding of the affect of tyre rupture, and my suggestions have been ignored.
Not ignored – maybe not agreed with or understood, but not ignored as evidenced by the number of responses you get


Likewise, an attempt to quantify would be based on data supplied from BEA, data I believe is lacking in sufficiency.
There is quite a lot of data in the BEA report that could be used in a quantitative way if one was so inclined.


It is BEA who proffered the photography, and begged the work, then did not perform it. Neglectful.
Or did not report it, which is not quite the same thing.

It was BEA who did not provide the chemical analysis of the rubber that may have proven the Titanium had been present in the tyre's carcass. In neglecting even the attempt to prove conclusively the strip was involved, they demean the discipline itself. Lazy.
But the BEA report stated


black marks were noted on the outer side of the strip and black elastomer debris was found jammed in one of the rivets. The spectra of these marks and deposits are similar to the Concorde tyre.


I don’t know what sort of chemical analysis you had in mind, but for me a spectral analysis of the material counts as a valid chemical analysis.


It was BEA that neglected elimination of material other than Titanium as the cause of tyre rupture, Cowcatcher/mount?

Are you now suggesting that the water deflectors somehow failed and got caught under the tyre? If so, how do you explain the curved failure on the tyre and the fact that the water deflectors were made of frangible material?

Was the area of the truck's mount inspected/analysed by BEA for abnormal wear? The landing gear had travelled several miles carrying two hundred tons, was the spacer's saddle worn?
Again I say yes, witnessed by their remarks...

The condition of the various pieces (shear rings, bronze bearings, seals) show that the inner shear ring had moved from its position incrementally during the last few flights. The marks indicate that the mechanism was operational although the shear ring was no longer in its position on the bronze bearings of the shock absorber and bogie.
The exact chronology of this displacement is, however, difficult to determine since the ring was not new and certainly bore marks related to its previous usage. The only marks observed on the mechanical parts correspond to movements in the vertical plane alone or to normal oscillations of the bogie.

Has anyone found an opinion on why the Captain's rudders were not planted full right? And held?

Yep! Just take a look at the figure presented in section 1.16.13.2.
By the time he got to the point you are discussing he was 2 deg off runway heading but heading back to the runway centreline (heading 270 against the runway’s 268). In addition the lateral acceleration at the cockpit had dropped to essentially zero. The aircraft was way above Vmcg even at the point of engine thrust loss, so why would he think he needed more drag producing rudder?


The report can be described in many terms. Exhaustive is not one such term.

Not many would agree with you there.

There is no reason to assume the shimmy was established in consistent fashion at any time, except for the three arcs of tread deposit we see. It could have been extremely irregular.

OK, so we can eliminate shimmy as a factor anywhere except where you found it after the aircraft left the tarmac?

An admission. I have not found the reference to shimmy in the Report. Therefore I do not know BEA's conclusions. I'm extrapolating on evidence I see, and read elsewhere and in the BEA work.

But the BEA report did contain a reference to shimmy

The Concorde landing gear manufacturer indicated that no cases of landing gear bogie shimmy had been reported. Examination of the parts revealed no such phenomenon.
Furthermore, the tyre marks left by tyre No 2 showed no signs of vibration or instability.

Therefore, the side load is left, and LEFT.....no balancing side load right. This demonstrates that at least in the area of the photographic evidence, the net load is constantly left. This means a bogie that is tracking well left of the longitudinal axis of the airframe.
Actually no, it doesn’t show any such thing, because the aircraft longitudinal axis was itself inclined to the aircraft path (sideslip).
Let me try another scenario on you.
The inclination of the bogie beam to the ‘normal’ setting would have been dependent on the balance of vertical and horizontal forces as BEA stated. Statically that would put the contact point at “12 o’clock” in the bearing housing., but again as the BEA state, the gear would be inclined to the vertical (camber). When rolling with intact tyres there would be no sideforce and the horizontal forces would be limited to the rolling friction – about 2~3% of the vertical forces. Not enough, I suggest, to move the contact point very far from 12.00.
It all changes after the tyre burst and loss of thrust. Now the horizontal force on each tyre is predominantly sideforce which would be proportional to ground reaction and tyre slip. When the aircraft started to diverge left under the action of asymmetric thrust the tyres became subject to right sideslip. When gear and tyres are intact this slip would produce forces pushing the aircraft left towards the runway edge and, because they act behind the CG, they would also make a small contribution to the yawing moment trying to return the aircraft to its original heading.
However, with the combination of a burst tyre and a sloppy bearing, the asymmetric side loads (two wheels aft, only one forward) would drive the bogie out of alignment in a sense to reduce the effective slip on the tyres to zero. In other words, if sideslip were numerically below the play in the bogie bearing the tyres would not be producing any side load at all!

So far as I can see, the aircraft was above this 2.75 deg limit for only a very short period between 97608 and 97613, which of course spans the time period at which you noticed shimmy, hence you can detect side load at that time.
This loss of sideforce would have reduced the lateral acceleration to the left (and runway edge) but would also have reduced the restoring yawing moment. But as argued above, the pilot had, and used enough rudder authority to bring the aircraft back towards the runway centreline.
Now factor in that the wing was carrying an increasing amount of lift in this period.
All of which of course begs the question as to whether this lateral displacement had any real consequences on the final outcome. My answer to that would be no, it didn’t, because when push comes to shove it was the failure to achieve a safe flying speed that mattered, and that was due to loss of engine thrust in a critical flight phase.
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Old 19th Dec 2012, 14:37
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Howdy Lyman
I can accept that the horizontal rotation is “abnormal” but as I said in post 223 “Where I do agree with those who don't accept the report or parts of it, is that the many other failures brought to the fore after this sad crash should be addressed but that doesn't mean that they actually caused the crash.” Can you therefore show where in the BEA report it says that the horizontal rotation paid a significant part in the outcome of the crash? A quote out of context cannot be considered proof.
Regards Nick
p.s Lyman: My forename is actually Nixon which will forever be linked with an attempted cover up!
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Old 19th Dec 2012, 14:56
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CliveL

Thank you for a reasoned and patient response. Here are some concerns I have.

I would not have entered the thread if France had upheld the verdict. Their reasons, I assume, have to do with a lack of compelling evidence in the public domain such that a standard of proof is unmet.

I would not be here if the accident had occurred in the USA. That France considers an accident scene as a crime scene is the threshold for my interest.
As such, the BEA document is thready, and missing some important work that imo should be present in a criminal prosecution.

Evidently France considers culpability on a par with crime. That makes no sense, imo.

The major issue is the apparent speed with which the report issues opinions, yet there is no lab or field work to support.

The strip was tested for evidence of non indigenous elastomer, with success. Yet an opportunity to take a further step was ignored, I think, when they apparently rejected the opportunity to test the tyre for presence of foreign material that may have been supplied by the chemically coated Tittanium strip.

As an example, then, BEA failed to provide irrefutable evidence that the Titanium strip destroyed the tyre(#2). WHY?

Simple. If they tested and found material, the case is made. If material was not found, the strip is found only to have generic elastomer, not necessarily Concorde elastomer.

So why risk it? The mission is not compatible with the purpose of the Court. Since BEA knows criminal prosecution is a given, their standards are low, by definition.

The Shimmy? Again an example of evidence that was taken, and left 'alone'....

You see the tyre skids, and can imagine the loads put on this airframe. I think your conclusion is that the shimmy would even itself out, and provide no net effect. What about vibration? Vibration may supply no net 'load', but have a very profound effect on the pilotage.

I contend that shimmy is not normal to heavy aircraft, and can be quite destructive, yet somehow the conclusion is that since the only evidence is after the fire, it was "inconsequential". Lack of evidence through lack of attempt is not sufficient; again, the prose in the report is used to put people in prison...

I don't disagree, necessarily, but again, the possibility is demanded to be explored to lack of consequence, not assumed to be so....

I value your time, as you know, and am grateful for the opportunity to discuss this with you.

Best regards
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Old 19th Dec 2012, 15:08
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Originally Posted by Lyman
I would not have entered the thread if France had upheld the verdict. Their reasons, I assume, have to do with a lack of compelling evidence in the public domain such that a standard of proof is unmet.
It was more to do with the fact that the opinion of the judge who oversaw the appeal differed from that of the judge who oversaw the original case.

As such, the BEA document is thready, and missing some important work that imo should be present in a criminal prosecution.
Have you read it thoroughly? It's a weighty document and I haven't covered all of its contents but it's about as thorough as one could hope it to be.

The BEA report is not intended to be (nor was it ever or should it be) a basis for criminal prosecution, it is simply a collection of facts and evidence (including the detail that - contrary to your earlier assertions - AF stopped using retread tyres since January 1996, BA having done the same since 1981) from which conclusions are drawn about the circumstances surrounding the accident. The document itself covers every aspect of the evidence and the accident sequence without assigning responsibility on the part of any of the parties involved.

The judges in the case had access to it simply as one piece of evidence, and the decisions regarding prosecution hinge on the representations made by the legal representatives of the involved parties - not the report.

As an example, then, BEA failed to provide irrefutable evidence that the Titanium strip destroyed the tyre(#2).
Incorrect - they (and others) used every technology available to them to assess the probability of the strip being the initiator of the destruction of the tyre, a process which was neither simple nor cheap (see report sections 1.16.5-1.16.5.4).

Their conclusion was that based on the probability of all the scenarios, the scenario whereby the strip contact was the initiator of the tyre's destruction made the most sense. They could not, and did not say any more than that.

As you correctly assert, the content of the report was not sufficient to prosecute on its own - and it was not intended to be. At the risk of repeating myself, the decision to prosecute was made by the judge based on the representations made by the legal teams of the parties concerned.

To make it as crystal-clear as I can, this and other BEA reports (like those of the AAIB) are never written with the intent of being used as prosecutorial aids. They tend to be very dry and scientific in nature (unlike those of the NTSB, which tend to be more forthright on assigning responsibility) and anyone who believes that the BEA has any say in the legal outcome of cases involving accidents is labouring under a significant misapprehension. The outcome of such cases is purely in the hands of the lawyers.

Last edited by DozyWannabe; 19th Dec 2012 at 15:34.
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Old 19th Dec 2012, 15:41
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Lyman,


As such, the BEA document is thready, and missing some important work that imo should be present in a criminal prosecution.
But that is where it all goes wrong, because BEA are at pains to state that their work is simply to establish causes not to present evidence for a criminal prosecution. You do them an injustice, I think, to view their work as preparation of a prosecution case.

Evidently France considers culpability on a par with crime. That makes no sense, imo.
In that you are at one with most of the Anglo-Saxon world brought up under common law, but it (Napoleonic law) is what they live by and we should respect that.

The major issue is the apparent speed with which the report issues opinions, yet there is no lab or field work to support.
I can't agree with you there - the report devotes fifty pages to discussion of laboratory work and testing. The long gap between the accident and issue of the report does not support your implication that it was all done in a hurry though does it?

Yet an opportunity to take a further step was ignored, I think, when they apparently rejected the opportunity to test the tyre for presence of foreign material that may have been supplied by the chemically coated Tittanium strip.
Others have commented earlier in this thread that the surface treatment of the strip might have hardness characteristics that would deter any transfer of material to the tyre. But I'm no tyre expert.

As an example, then, BEA failed to provide irrefutable evidence that the Titanium strip destroyed the tyre(#2). WHY?
Simple. If they tested and found material, the case is made. If material was not found, the strip is found only to have generic elastomer, not necessarily Concorde elastomer.
So why risk it? The mission is not compatible with the purpose of the Court. Since BEA knows criminal prosecution is a given, their standards are low, by definition.
As I said earlier, the BEA mission was not to provide evidence for the judiciary. If the latter wanted additional 'proof' to cement their case they were perfectly entitled to demand it.

You see the tyre skids, and can imagine the loads put on this airframe. I think your conclusion is that the shimmy would even itself out, and provide no net effect. What about vibration? Vibration may supply no net 'load', but have a very profound effect on the pilotage.
I don't like to 'imagine' loads put on any airframe. What I see is that in the time period where shimmy appears to be present the ground reaction on that gear was modest indeed, and the loads transmitted to the airframe would be correspondingly modest. So far as vibration is concerned I have already agreed (with Chris Scott) that vibration continued into the airborne part might have been a contributory factor to the decision to shut down #2 engine.

I have to say though that there is no sign of any 7 Hz variation in the lateral acceleration trace, and the normal acceleration traces show nothing higher than 1 Hz and even that dies out once airborne.

I contend that shimmy is not normal to heavy aircraft,
Indeed so but as part of my researching this topic I found a presentation that implied the C17a gear might be shimmy prone. I have no more evidence but that, although the implication of the presentation was that four wheeled bogies are not usually prone to shimmy, and of course most heavy aircraft are so equipped. The C17a gear however is a three wheeled device if I have understood it correctly

Lack of evidence through lack of attempt is not sufficient; again, the prose in the report is used to put people in prison...
And again, the purpose of the BEA report is specifically NOT to put people in prison. If other parties seek to use it so that is their affair. We would all agree however that seeking to use data accumulated in accident or incident analyis is counter productive to the cause of improving aircraft safety standards

Regards

PS Writing that whilst Dozy was posting changed the phasing, but I see that we are both saying essentially the same thing re the purpose of the BEA report.

Last edited by CliveL; 19th Dec 2012 at 16:32. Reason: deleting a comment
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Old 19th Dec 2012, 16:29
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CliveL

Yes, I referred back to my post thanking you for yours and found yours missing.



Until its return, may I make a single point? From the photographic evidence at the area around the shorn runway lamp, we seem to be in agreement that horizontal movement of the wheel truck is apparent. it suggests a powerful oscillation (to me), one that may have had an effect on the early rotation, subject thus far only to speculation, and dependent perhaps on my observation of the tyre marks....

Since BEA have provided the photographic evidence to the public, and have also dismissed the possibility of horizontal oscillation gleaned from that very image, may I suggest that that constitutes the possibility of a glaring error in the report?


And one question? Do you believe the skid marks evident parallel the centerline in the BEA photo (of the carbon trail and kero stain) represent the Concorde's path?

************************************************************ **

Nick Thomas

Howdy do. There is no record to my knowledge that BEA made any representation at all of Bogie involvement in the wreck, So allow me to offer the importance of the spacer in the accident.

Let us for now say that there was no Titanium strip, and the tyre did not burst. Let us offer further that engine failure did occur, for reasons unrelated to fod, and the a/c veered leftward. This sets up horizontal movement of the bogie, and side loads on the tyres of the left MLG. Without the spacer, the bogie oscillates and vibrates. Depending on the mechanism of bogie disablement, and the clues and cues in the cockpit, might the FE have pulled #2 as he did in the actual wreck?

This was the third take off for this bird without the spacer, essentially each one a test flight, as regards landing gear. The shimmy is denied, as we see, in the report, while I maintain that it is quite possible the wreck was doubly damned, it might have crashed due the landing gear issue alone. (grantng engine failure/shut down).

Last edited by Lyman; 19th Dec 2012 at 16:48.
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Old 19th Dec 2012, 16:41
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Originally Posted by Lyman
Since BEA have provided the photographic evidence to the public, and have also dismissed the possibility of horizontal oscillation gleaned from that very image
Your language is misleading - they have not "dismissed the possibility" or anything of the sort. In fact Section 1.18.2 goes into considerable detail regarding the evidence they were presented with regarding the bogie (in spite of your claim that they made no reference to it at all). They simply consider it to be less likely to have had a significant effect than the metal strip contact, and with good reason.

If you're not inclined to take my word that the BEA report is merely a presentation of evidence (in the manner of an initial crime scene report with ballistics and forensics) - would you consider Clive's word on the matter?

Last edited by DozyWannabe; 19th Dec 2012 at 16:52.
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Old 19th Dec 2012, 16:51
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I have been searching CliveL's post for the quoted language from BEA that rejects any involvement of the oscillation, that there even was one. It seems to have been censored out.

Would you be able to locate it?

From the ruddering the Captain did, and the direction of the a/c well left of the runway heading, is it possible to surmise that something about the ruddering prompted Captain to give up, and accept a takeoff off runway as his best chance?

At the beginning of the veer left, to the take off point, there appears no correction right. Right rudder may have exacerbated the side load on the left bogie, and made any problem with the gear bad enough to cause him to abandon rudder as correction?

Last edited by Lyman; 19th Dec 2012 at 17:02.
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Old 19th Dec 2012, 16:54
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The (English version of the) report is here:
http://www.bea.aero/docspa/2000/f-sc...-sc000725a.pdf

Read it at your leisure, but the content regarding the bogie is in section 1.18.2 (and its subsections).

Regarding rudder input:

Originally Posted by BEA Report S1.18.2.5 P155
During the takeoff run, the aircraft would have had a tendency to deviate to the left if the left main landing gear had created abnormally high drag. However, its track was straight before the loss of thrust on engines 1 and 2 and there are no observable right rudder inputs. On the contrary, some slight actions to the left are even noticeable before V1.
In effect, the rudder inputs were *opposite* what would be expected if the missing spacer had an influence on the aircraft track prior to contact with the strip.

Last edited by DozyWannabe; 19th Dec 2012 at 17:05.
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Old 19th Dec 2012, 17:03
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Many thanks Doze...

aloha

Here it is...From BEA report

(from CliveL post #264)

Quote:
"The Concorde landing gear manufacturer indicated that no cases of landing gear bogie shimmy had been reported. Examination of the parts revealed no such phenomenon.

Furthermore, the tyre marks left by tyre No 2 "showed no signs of vibration or instability."

That is what is known as a discrepancy......

Last edited by Lyman; 19th Dec 2012 at 17:25.
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Old 19th Dec 2012, 17:09
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It suggests a powerful oscillation (to me), one that may have had an effect on the early rotation, subject thus far only to speculation, and dependent perhaps on my observation of the tyre marks...
By the time any evidence of oscillation is observed the aircraft was 9 seconds into a 10 second rotation, so I can't see how it could have had any effect on the earliness of the rotation. There is, as I said, no evidence of any vibration at the frequency you suggested for shimmy (7 Hz if I recall correctly) during the airborne part of the rotation through to the screen, so I conclude the oscillation had no practical effect.

Since BEA have provided the photographic evidence to the public, and have also dismissed the possibility of horizontal oscillation gleaned from that very image, may I suggest that that constitutes the possibility of a glaring error in the report?
You wouldn't have found any prior remarks in any of my earlier postings (your #271) - this is the first. They didn't, so far as I can see, dismiss the possibility of horizontal oscillations during rotation - they simply did not discuss it. All their remarks on loads and shimmy seem to be related to the conditions existing prior to development of any significant sideslip. Fig 73 (English version) for example specifically shows the force balances in a possible bogie deflected condition but with the aircraft following a zero sideslip path.

I have no idea why they did not discuss the bogie behaviour in the rotation unless, like me, they came to the conclusion that it had no significant effect. This at least would be consistent with their statement that the missing spacer was not a factor. Even so they might, perhaps should have mentioned it - but that omission doesn't really change anything.

That is what is known as a discrepancy......
Not if I am correct in suggesting that all their comments relate to the conditions prior to any significant deviation from straight path. NB, I have edited the original to correct the reference to pre-tyre failure conditions.

Last edited by CliveL; 19th Dec 2012 at 17:35. Reason: additional remark
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Old 19th Dec 2012, 17:16
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Originally Posted by CliveL
They didn't, so far as I can see, dismiss the possibility of horizontal oscillations during rotation - they simply did not discuss it.
Well, they mention it in the section you quoted (18.2.3.3), and then go on to discuss what effect that would have had, compare that effect to the evidence presented and conclude that it was unlikely.

I have no idea why they did not discuss the bogie behaviour in the rotation unless, like me, they came to the conclusion that it had no significant effect.
Also, at rotation, the fuel fire had been ignited and presented a significantly more clear and present threat to the safety of the aircraft than anything else. I'd say it's understandable that the report focuses on that from that point onwards.

There are a couple of paragraphs which refer to the camber of the bogie post-tyre failure compared with normal:

When the four tyres are correctly inflated, the vertical load transmitted by the bogie beam takes the axle to its upper stop on the bronze bearing of the fork on the shock strut (shock absorber). This generates a camber angle of around 2.5°. The load applied on the two outer tyres (No 1 and 5) is then increased by around 20% whilst the load applied on the two inner tyres (No 2 and 6) being diminished by the same amount.

After the burst of tyre No 2, the load that it was bearing was redistributed between the outer tyres. Consequently, a new equilibrium was generated around its axle on the outer shear ring, the camber angle returning to practically zero.
so there is evidence that the behaviour post-failure was at least studied.

Last edited by DozyWannabe; 19th Dec 2012 at 17:22.
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Old 19th Dec 2012, 17:18
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CliveL

When the BEA mention "tyre marks made by tyre No. 2", are they referring to only prior to tyre burst? That means there were tyre marks visible prior to burst, so I ask again, do you note the tyre marks in the photo of the kero stain, carbon trail?

Well certainly the bogie may not have been involved, but we see it was, though post burst/fire......

I am sorry to harp, if it appears so, if you say it is not relevant, I accept that, certainly.....

I understand the possibility of oscillation in the horizontal is believed to be of no consequence to the accident. But I will not admit it did not happen in the take off roll, and dismissing that portion of a serious anomaly seems counter to a full understanding of the events....
best

Last edited by Lyman; 19th Dec 2012 at 17:28.
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Old 19th Dec 2012, 17:26
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Originally Posted by Lyman
When the BEA mention "tyre marks made by tyre No. 2", are they referring to only prior to tyre burst?
Think about it logically. Post-tyre burst there would be no "tyre marks" in the usual sense of the term, as the tyre has been destroyed. From that point on it would be "debris trail" or "rubber marks".

Last edited by DozyWannabe; 19th Dec 2012 at 17:27.
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Old 19th Dec 2012, 17:31
  #278 (permalink)  
 
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Dozy, there are marks of tyre number two up to leaving the ground.

There are marks that likely show the shape of the carcass deficit caused by the rupture/burst.

So let me ask you.

Describe the tyre marks you see prior to the kerosene stain in the long photo. the ones that continue along the centerline.

I have some follow up questions.

Last edited by Lyman; 19th Dec 2012 at 17:32.
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Old 19th Dec 2012, 17:37
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so there is evidence that the behaviour post-failure was at least studied.
Yes, but not in the phase where there was appreciable aircraft sideslip
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Old 19th Dec 2012, 17:40
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But I will not admit it did not happen in the take off roll,
OK, if that is your view then fine; but I see no evidence or know of any physical explanation that would support your position.
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