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Nose wheel falls off Boeing 757 airliner waiting for takeoff
(www.theguardian.com)
This is a most excellent place for technology news and articles.
may be, it could also mean that boeing didn't adequately specify the kind and amount of maintenance that has to be done. it could also mean that delta changed the maintenance procedure so much that this failure could occur.
there have been many cases where either has led to catastrophic failure