Composites Delamination

[prionsa]

How's it goin guys,

I'm doing a study on delamination in composite materials,(Aeronautical Approach) Wondering if anyone has any knowledge of a past important incident where it was a factor?

Cheers.

[gas path]

Try a goooogle for 'concorde rudders'

[prionsa]

yeah ive been looking around for a while and im struggling to find an solid incident to write on, concorde hasnt come up before but ill give it a go.
thanks!

[nodrama]

Try Airbus 300-600. I seem to remember that the a/c that crashed days after 9/11 due to the tail coming off was because the tails composite attachment lugs failed.

Also look for EC155 (helicopter) tail fin loss in flight. Also due to composite material failure.

[carholme]

Here is the link to Transport Canada review of the Air Transat 961 flight from Varadero, Cuba to Quebec City:

http://www.tsb.gc.ca/eng/rapports-re...7/a05f0047.pdf

Also type in any search engine "Air Transat Rudder failure" and you will also find the series of photos of the failed unit.

Regards

carholme

[prionsa]

thanks very much carlhome, i appreciate your help.

[carholme]

prisona;

You are welcome and I hope it helps with your study.

carholme

[prionsa]

if anybody is interested, there's a nice report of concorde rudder delamination here, unlike others its straight to the point. must have been written by an engineer

ASN Aircraft accident Aérospatiale / BAC Concorde 102 G-BOAB North Atlantic

[blakmax]

Delamination or disbond?

I hate to be pedantic, but the use of the generic terms "composites" and "delamination" can lead to entirely confusing outcomes. Many people uderstand the term "composites" to mean a laminated material fabricated from fibres and resin, while others (including unfortunately the FAA) include adhesive bonding in that terminology.
Similarly, many people use the term "delamination" to describe the separation between plies in a laminated composite, while others also use the term to include a separation at a bonded joint. Again, these are distinctly different failure modes with different causes. Delamination in a laminated composite is often associated with impact damage, while disbonding of an adhesive bond is often a direct result of manufacturing processes and in most cases has little to do with the service history (even if manufacturers often try to blame the user).
The Concorde failure referred to in the previous posts is a classic case of this confusion. The report assigns the failure to bonding issues, not delaination of laminated composite materials.
These are two enitrely different technologies in which the only common factor is that the stuff used is initially sticky and is cured by heat. There are very distinct differences in design methodology, materials, processing methods, training and failure modes. Just because a technician knows how to laminate a composite component does not necessarily imply competency in surface preparation to bond that component. So why do people still continue to use poor and confusing terminology?

[Lightning5]

Try AA A300-600 that went down in NY suburbs shortly after TC accident. Flight was NY to Santo Domingo and the rudder and fin came off after following Jal 747 out of JFK.