Boeing Co. will roll out new versions...

Boeing Co. will roll out new versions of its 737 and 747 airliners today, two aircraft which should help the Seattle-based company hold its position as the world’s leading commercial aircraft maker. The new 747-400 is a fuel-efficient model able to fly 16 hours nonstop. The short- to medium-range 737-400 will make it possible for Boeing to continue delaying the development of its 7J7, an aircraft driven by a new type of prop fan engine. The company has advance orders for 117 of the 747-400 aircraft and 88 orders for the 737-400.