AC

Boeing's 737 — the commercial jet that made its debut in 1968 and the one you've most likely flown on — is getting a makeover to fit with the new demands of air travel in the 21st century. The new version, the 737 Max, which is scheduled to make its debut in 2017, is designed with new engines to burn less fuel than its three predecessors, to help airlines pare costs and leave less of a carbon footprint on the global environment. But at its most basic, the Max will be the same 737 stalwart the traveling public has come to know the last 44 years. It's a single-aisle jet that will ferry up to 215 passengers on both short and cross-country trips, and offer efficiency that's helped make the 737 the best-selling commercial jet in history, with 9,745 sold. "They're known as the workhorse of the industry," says Mike Van de Ven, COO of Southwest Airlines, which has exclusively flown 737s since the airline's birth in 1971. "It really beats the competition on fuel burn. It really beats the...