The brains over at MIT have come up with a new, fuel-efficient airplane design that is purported to use 70 percent less fuel than current airliners. Though modern day jet engines burn less fuel at slower speeds than the early designs of jets in the '50s and '60s, airplane designs haven't been updated to take full advantage of this efficiency. “From a purely design viewpoint, they’re really mismatched," said Mark Drela, the lead designer on the MIT team. "The big engines want to go slower, which means the airplanes really want to have less wing sweep.” Though the new jets would fly at a slower speed, overall flight time wouldn't be dramatically longer, according to the designers, because of a wider fuselage, which means less time for loading and unloading passengers. The fuel-efficient design was presented to NASA, which could potentially develop and test the next-generation planes.