Airbus, seeking an edge over Boeing Co. in the contest to supply single-aisle planes to US carriers, has begun pitching a version of its A320s with wider aisle seats that airlines can market for additional revenue. The planemaker has begun talking to several US carriers about the concept in recent weeks after getting B/E Aerospace Inc. to design a prototype. The A320\'s seven-and -a-half inch advantage in cabin width over the Boeing 737s would let Toulouse, France-based Airbus offer 20-inch aisle seats by reducing the middle and window seats to 17 inches, equivalent to the 737. \"Airlines are improving their margins by charging for bags, window seats and food,\" said John Leahy, chief operating officer for customers at Airbus. \"But what most people really want is space, and that\'s what we can offer. Every economy-class aisle seat would be almost as wide as a first class seat on competing aircraft.\" Adding two inches to one third of the seats in an A320 would hand US airlines a marketing tool that they could target at the obese population, which has swelled to more than one-third of US adults, according to Data from the National Health and Nutrition Examination survey. Airbus has sought to win more business with US airlines and wean them off the 737, which remains the world\'s most widely flown commercial aircraft.