Who will supply all the parts?

A big factor in 7E7 site selection may be proximity to Boeing's suppliers, who would deliver major sections of the plane directly to Boeing's plant.

Boeing has long acknowledged that every plane it builds contains thousands of parts built by domestic and foreign suppliers. The "build vs. buy" ratio is normally 30 percent of parts built by Boeing and 70 percent built by suppliers.

The 7E7 would take Boeing's reliance on outside suppliers to a new level as it embodies high-level engineering and "systems integration." That means its suppliers would assemble parts into major sections of the plane. 7E7 suppliers could even do work that up to now has been closely guarded by Boeing, such as construction of the wings and assembly of large fuselage sections.

The composition of the parts themselves also would be dramatically different. Boeing announced Thursday that for the first time in commercial-airplane history, the wings, fuselage and tail of the 7E7 would be made primarily of lightweight carbon-fiber composite materials rather than aluminum.

Boeing did not say who would build those parts, but there is heavy betting that Japanese manufacturers would get much of the work.

Such outsourcing deals are anathema to Boeing's unions, but the company considers them essential to keep foreign airlines from flying Airbus jets.

Boeing is also expected to ask some suppliers to act more like investors on the 7E7. That means suppliers funding more of their own research and development and taking equity stakes in the 7E7, so they would have a greater financial incentive to minimize the costs of their parts and to help Boeing market the plane.