Composite material
 

Hope its not a repost, I've searched:)
Just thought I share:cool:
Quote "very crack resistance". Still extremely expensive, but could be part of aviation's future, or should I say commercial aviation future
http://www.space.com/businesstechnol...l-CentrAl.html

Interesting article, CH274. My perception is that helicopters are more conservative in materials usage than fixed wing. This is most likely because the level of vibration that a helicopter fuselage and mounting structures have to withstand are an order of magnitude above their fixed wing counterparts. Also a big part of fixed wing loading is the pressurisation, which tends to dictate the material thickness

Fatigue on a good day can be a tricky beast to predict. I also get the impression that crack repairs are more acceptable on helicopters, probably because the crack will not immediately cause a catastrophic decompression. Obviously a newer composite will not have had the repair techniques developed yet.

A laminate of several layers would obviously be more crack resistant as is true of all laminates.
But how it would be 25% stronger as the article stated than solid 7075-T6 aluminum is unclear to me, since the layers of fiberglass will not carry much of the load. Fiberglass has a much lower modulus of elasticity than the aluminum layers.