These days, a sedan that only runs 5 miles per gallon would be laughed off a car lot.
Yet in the air - where Boeing 747s get about .2 miles to the gallon - that kind of gas mileage would be revolutionary.
Like their automobile counterparts, airplane engineers have been looking for ways to safely send those 70-ton metallic birds into the air on a leaner fuel diet to cut down on carbon emissions and rising transportation costs.
Earlier this year, engineers Geoffrey Spedding at the University of Southern California and Joachim Huyssen at Northwest University in South Africa put their heads together to tackle that airplane fuel efficiency conundrum.
After reconfiguring the typical plane design in order to maximize the plane's aerodynamics, they came up with a brilliantly basic answer: Airplanes should look more like birds.
A more aerodynamic plane would reduce drag (resistant friction) as it cruises through the air and increase lift (upward propulsion), which translates to better fuel economy.
"The design of an aircraft is a complex and large system design problem, with many interacting components and constraints," Spedding said. "Our logic is to first of all look at the aerodynamic consequences alone of this proposed aerodynamic improvement. If that does not work, then there is no sense in going further."