Ok, even I’m prepared to admit this article is a little biased towards the Euro’s, just a little, bit it makes interesting reading….
From The Engineer, 11 June 2004
Rushed and ridiculous
By Richard Fisher
Airbus has attacked the high proportion of composites used in Boeing’s 7E7 Dreamliner, branding the aircraft’s development ‘rushed’ and ‘ridiculous’.
The 7E7 will contain double the amount of composites used in the Airbus A380 – including most of the fuselage and wings. But Airbus claims Boeing has rushed through the technology before it is sufficiently matured.
Colin Stuart, Airbus vice-president of marketing, said composites should be introduced with caution in aircraft design. ‘If you start to look at the various loads on composites [in an all-composite fuselage], it is absolutely the wrong thing to do.’
Current composite material is unsuitable for many areas of the fuselage claimed Alain Garcia, executive vice-president of engineering. ‘It’s perfect for tension and fatigue, but poor for compression.’
Airbus has stepped up the war of words with Boeing after the US company criticised weight increases in the A380. Airbus claims the 7E7 will be heavier than Boeing has admitted. ‘The 7E7 carries the weight penalty of a compromised and rushed design,’ the company said.
Dr Jürgen Klenner, Airbus senior vice-president of structure engineering, said today’s carbon fibre is often no more than ‘black aluminium’ — with the same attributes as traditional materials — offering few benefits for the extra cost. Carbon fibre does have weight advantages, but according to Klenner the cost of the raw material is up to 500 per cent higher. ‘We do not apply a material because it is trendy, we do it when we are convinced it is mature enough. There are crucial questions that have not yet been answered,’ he said.
There are concerns that composites present a higher fire risk, delaminate in humid conditions, and are more expensive to repair. Prof Phil Irving, civil aviation authority expert in damage tolerance at Cranfield University, said engineers should dripfeed composites into aircraft design to avoid ‘unexpected failures. ‘There is always a risk when introducing something new on to an aircraft, no matter how many tests. There’s always something we haven’t realised.’
Bird strike, stones or taxiing accidents would greatly reduce the compressive strength of composites such as carbon fibre. ‘You can avoid the problem by making it thicker, but that has economic implications. It’s rather difficult to see how you can have a whole fuselage made of composites.’
Airbus chief executive Noel Forgeard claimed the 7E7 would have identical technology to the A380. ‘This is why Boeing has strongly discounted it to sell it,’ he said. Airbus accused Boeing of tinkering with the 7E7’s supposedly advanced technology during its development, saying the final product will be more conventional and heavier than originally claimed.
Stuart said: ‘They have rushed this aircraft through in a ridiculous way.’But Boeing denies this, pointing out that the aircraft was developed in parallel to, rather than after, the company’s now-cancelled project, the Sonic Cruiser.
A Boeing spokesman said: ‘We’ve put a great amount of work into composites, drawing on the work we’ve already done on the 777 and a whole variety of military aircraft. The 7E7 is a bold move, but if you look at the efficiency and environmental advantages it’s a move in the right direction.’
The 7E7 will contain 50 per cent of its weight in composites, making it lighter and more fuel-efficient, Boeing claims. The A380 structure contains under 25 per cent composites, while Airbus chose not to use the carbon fibre wing planned for its future military aircraft.
Boeing announced this week it expects up to 200 orders for the 7E7 in 2004. Only Japan’s All Nippon Airways and Air New Zealand have placed orders, compared with 129 orders to date for the A380.
Airbus’s approach for the A380 is in sharp contrast to Boeing’s claims for the smaller Dreamliner. Airbus is focused on shipping up to 550 people between megahub airports, while Boeing believes flying faster and lighter point-to-point is the future of air travel.
By: coanda - 17th June 2004 at 20:00
thanx for that post distiller, it mostly makes for interesting objective reading.
Airbus plainly have nothing to hide, and the only problem they face is the fact that statistically thare is more chance of injury during a practice evac. why impose harm during a practice if it can be done differently but safely?
the pyschology paper points the finger of blame at hesitation due to height and or confusing constructions. given the urgency of an evacuation procedure, i certainly wouldnt be hesitating!!
The problem of injury due to jams at the bottom of the slide seems to be somthing that needs dealing with.
I agree that actual practices need to be carried out, but a full scale evac could (and is allowed by faa regs by the looks of things) be missed quite legally and acceptably.
if there is research going on at cranfield, then you will have a hard time trying to disprove the validity of it.
coanda
By: Distiller - 17th June 2004 at 17:55
FAA evac guidelines:
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/B06344339E7CC2BF8525667200515170?OpenDocument&Highlight=25.803
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/E04D912FA5C6E72785256673004F714B?OpenDocument&Highlight=25.803
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCir…
Airbus fears evac tests and wants to avoid a real-world test:
http://www.iasa.com.au/folders/Safety_Issues/others/airbus_in_fear_of_full_emergency.html
On the psychology of evacs:
http://www.gp.tu-berlin.de/users/j/helmut_jungermann/artikel/atlantic%20city.pdf
FAA on the A380 evac:
http://www.faa.gov/ats/asc/nlaweb/Downloads/PPT/DCN%20ARFF%20for%20NLAFG%2005-13-03.ppt
By: Bmused55 - 17th June 2004 at 17:44
I still think Airbus should have to put the exits to a real live test.
Or do Airbus have something to hide?
By: coanda - 17th June 2004 at 15:54
exactly…….
and would running through with real practice show up these problems any better than computer models??
i think that models have been validated against existing escape practices on other aircraft.
coanda
By: GZYL - 17th June 2004 at 15:50
I seem to remember that the regulations concerning evacuation of aircraft say that you have to get everyone off the aircraft in 90 seconds, using only half the exits. This means that you’ve got to get somewhere in the region of 1 person going down the slides every second… roughly speaking! The problem with evacuation of the A380 comes in the top deck… it’s high off the ground… so if you have say an 80 year old frail woman… terrified, because of the emergency…. stood looking out of the door on the top deck of an A380 thinking it’s a bloody long way down to the ground… and just freezing… not moving… this means people are trapped and could make the difference between life or death.
By: coanda - 17th June 2004 at 15:16
apparantly airbus have researched and helped put together (monetarily and otherwise) ground breaking research in the field of emergency evacuation, as they were breaking new ground, i seem to recall. there was a RAeS article on it a while ago.
perhaps the caa is happy with this information??
By: Bmused55 - 16th June 2004 at 15:39
interesting.
It is at all possible for an aircraft to get certified without a physical certification of the evacuation procedures and slides? Surely not??
A lame excuss by Airbus who are no doubt sh!tting their pants that the A380 could fail to be certified on grounds of the evacuation slides.
no certification means no flying that mean no sales and no more airbus.
By: coanda - 16th June 2004 at 14:30
any fibrous panel composite is worthless in compression, the only thing that can resist compression forces in a panel type fibrous composite is the matrix. and the matrix has a small resistance to compression.
As long as the forces are planar there will be little risk of delamination. this is probably the reason that its used where it is, the forces will be trasmitted along the material.
force direction means allot in composites.
that article sounds like airbus think boeing havnt done their homework on composites. in reality both companies have a relatively long experience and exapnsive knowledge of composites. They also have the right tools to analyse the problem.
composites are relatively new in the manufacturing world, in the scales we are talking about here, so things like the fracture mechanics of all the different lay-ups and the all the different materials is going to be junior to alloys….but its advancing quickly.
there is a substantial field for things like modelling escape procedures and exits. these things include a factor for human randomness under pressure…statistics is good for somthing after all!!
airbus are right that it is likely that someone would be injured during emergency evac procedures given the height of the upper row of emergency doors. But i suppose that prevention of injury is a lame excuse for not testing these things.
does anyone have any information on the validity of emergency escape tests and the frequency with which these systems are used???
coanda
By: Bmused55 - 16th June 2004 at 11:55
Talking of GLARE … I never understood why they use fibreglass and not some other fibre.
And I think the chances for GLARE to de-laminate are as high or even higher than for the carbonfibre/epoxy composite and titanium graphite laminate Boeing uses on the 7E7.
And I hate when the PR-guys spit out their gloom-and-doom propaganda about something being unsafe. That hurts the industry. And esp Airbus and EADS have a very aggressive and non-factual based propaganda. There is a difference about saying “we are better” or saying “they are bad”. Typical negative European propaganda. And I’m not whining. Just the facts.
And the sole reason for the A380’s aluminum wing is the huge and expensive milling machinery BAE Systems has at Broughton. And they know that the 7E7 is more advanced and now they run their FUD campaign to obscure that fact.
You hit it on the nose Distiller!
By: Tempest - 16th June 2004 at 10:33
That sounds like a plausible explanation, Distiller. Sound’s like BAE are trying cover themselves for not investing money in more modern techniques. Makes sense – the article coming from a UK Engineering mag.
I must say also I find it pointless when B and A fight over these things. Boeing used to carp endlessly about Airbus’s FBW system when they launched the A320, so this kind of thing goes back a long way.
By: Distiller - 15th June 2004 at 15:29
Talking of GLARE … I never understood why they use fibreglass and not some other fibre.
And I think the chances for GLARE to de-laminate are as high or even higher than for the carbonfibre/epoxy composite and titanium graphite laminate Boeing uses on the 7E7.
And I hate when the PR-guys spit out their gloom-and-doom propaganda about something being unsafe. That hurts the industry. And esp Airbus and EADS have a very aggressive and non-factual based propaganda. There is a difference about saying “we are better” or saying “they are bad”. Typical negative European propaganda. And I’m not whining. Just the facts.
And the sole reason for the A380’s aluminum wing is the huge and expensive milling machinery BAE Systems has at Broughton. And they know that the 7E7 is more advanced and now they run their FUD campaign to obscure that fact.
By: Whiskey Delta - 15th June 2004 at 15:21
Trying to skip an actual aircraft evacuation demonstration for certification doesn’t sound like Airbus trying to take extra measures.
By: Bmused55 - 15th June 2004 at 15:05
LMAO! Thats a good one.
I don’t think airbus should not be allowed to forgo such a test, its just not right.
EDIT: Erm, forgot the word NOT after should :rolleyes:
By: Whiskey Delta - 15th June 2004 at 15:02
It would be to large to handle safe evacuations was something I recall Boeing said.
I don’t remember Boeing ever calling the A380 unsafe but they did attack the attempt by Airbus to skip a full A380 evacuation demonstration for certification purposes. Airbus claimed that such a demonstration would only result in injuries of the participants.
By: Bmused55 - 15th June 2004 at 11:59
Freudian slip of spelling :rolleyes:
By: Dutchy - 15th June 2004 at 11:57
Hear hear you mean? If it doesn’t kill them it will make them stronger yes.
By: Bmused55 - 15th June 2004 at 11:35
I’m delighted that after many years of Airbus forcing Boeing to be on their toes Boeing are now going to give Airbus the shove that they need to avoid complacency. A good war between manufacturers can only be good for the end user with improving products. Long may it go on (in both directions)!
here here
By: wysiwyg - 15th June 2004 at 11:19
I’m delighted that after many years of Airbus forcing Boeing to be on their toes Boeing are now going to give Airbus the shove that they need to avoid complacency. A good war between manufacturers can only be good for the end user with improving products. Long may it go on (in both directions)!
By: 4 engines good - 15th June 2004 at 11:07
Both companies are as bad as each other trying to undermine the other one, instead of concentrating on their own projects. Boeing does have a tendency of announcing the development of new aircraft, sometimes when it has no intention or realistic chance to build it, to undermine Airbus’s new projects. And Airbus does have a tendency of having a go at Boeing on the safety or alleged carelessness of its new products.
That kind of policy is reprehensible and it is high time both companies learnt to work in a more positive way. This cut-throat business is not good for the industry and if either of the companies were to go bust there would be many more losers than winners on both sides of the Atlantic.
By: skycruiser - 15th June 2004 at 10:47
Hmm
Airbus: A spoiled child having a tantrum because things aren’t going the way it wants them to go.
The thing about the weight is utter crap. Boeing have a long long history of exceeding their targets. They were doing so 30 years before Airbus was established, they continue doing so and will go on doing so.
Airbus are the opposite, they have a history of barely meeting and sometimes failing the targets they set out in regards to weights and performance. Airbus know this, they know that the A380 is already overweight and are probably worried.
Yes, definately a strop by airbus. Expect a counter claim by Boeing soon
spot on B55.
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June 13, 2004 at 7:20 pm