The 787 is the first airliner made mostly from lightweight composite materials, which increases an aircrafts fuel efficiency.

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Part of the Dreamliner's appeal to airlines is its increased fuel efficiency due to its construction of lightweight composite materials instead of metal.

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Airbus' A380 superjumbo and Boeing's upcoming 787 Dreamliner both use new engine designs, lightweight composite materials and advances in aerodynamics to improve performance, increase fuel efficiency and lower emissions.

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