By John S. McClenahen Boeing Co., Seattle, is literally on the move -- again. Having announced that it will relocate its corporate headquarters to Chicago, Dallas, or Denver by fall, the aerospace company is shifting fuselage assembly of its 757 narrow-body, twin-jet from Renton, Wash., just south of Seattle, to Boeing's Wichita, Kans., site. The move, which is being done to increase production efficiency, is expected to be completed in two to three years. The move is expected to affect about 500 people in Renton, who will be offered jobs elsewhere in the company, Boeing says. Meanwhile, Boeing will be working on what the company terms a "radically different" commercial airplane. "We are developing designs that would reduce flying time as much as 15% to 20% while achieving ranges not possible with current airplanes," says Alan Mulally, president and CEO of Boeing Commercial Airplanes. "These airplanes also will fly higher than current models, offering a more comfortable ride for passengers," he adds. Although Mulally does not mention it, Boeing may be drawing on the R&D work it's already done for a U.S. supersonic transport as it designs its new aircraft.