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| The new Air New Zealand Dreamliner; photo from CNN.com here |
This strays from "Geology In Motion," but I can't resist--the Boeing 787 "Dreamliner" is truly a beautiful plane in flight! It's wings can flex up to 26' (150% of max load). All aircraft are required by the FAA to be able to withstand at least three seconds of 150% maximum loads (on all structures). In January, 1995, a 777's wings deflected 24' at 154% max load (I couldn't find the actual data to check the facts--I'm using www. flightglobal.com.) Boeing actually did a break test, which you can see in this Boeing produced video. They do not say how flexed it was when it failed, however, only that it was beyond 150%! Here's a cool video (in German) of a lab test showing the flex in a way that you can actually see-it's huge--definitely worth watching this one all the way to the end to see the failure! Here's an explanation that I found on this aviation.stackexchange.com site:"The amount of flex is really a product of the material. The wing requires a specified ultimate strength; with metal, that translates into a given amount of flex. This can be varied within limits, but it is really the material, its stiffness to yield point ratio, and its fatigue properties, that control how much flex you are going to end up with. CFRP is a very different material, and has much less stiffness for the same yield point, and has essentially no fatigue problems. This is beneficial in that it provides a smoother ride in turbulence; the wing acting essentially like a giant leaf spring. There is some lift lost due to the nature of the curvature, though. However, this is relatively small."
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