https://boeing.mediaroom.com/2010-03...20295_1138-117
As to body - how many large autoclaves with several hours cycle times plus layup and bagging tooling would it take to maintain a high production rate- and then there is the making of carbon fiber,etc. probably an overall cost versus rate issue compared to possible improvements.
As to wet conditions- A6 REwings of composite have been around for over a decade
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