The Economist has an article on aircraft designs that could cut fuel use by 50-70%, while still working with today’s airports (a challenge for flying wing designs). From the article:
Two groups working on the future of aircraft have come up with designs that could meet the practical needs of the industry and still cut fuel consumption by half. These researchers, at the Massachusetts Institute of Technology (MIT) and Imperial College, London, rely largely on existing technologies for many of their designs.
If a B737-800 was morphed into the shape of one of the D-series of aircraft on which Mark Drela is experimenting in MIT’s wind tunnel, then it would be about the same size, could fly the same routes and would carry a similar number of passengers. But the D8.1 version (which could be built conventionally, from aluminium) would use 49% less fuel. The D8.5 (similar, but constructed from composite materials expected to be available by 2035) would burn 71% less.
Read More: The aircraft of the future: Plane truths | The Economist.