Boeing South Carolina (copy)

Boeing Co. says a demonstrator fuselage used to test new manufacturing processes isn't related to a proposed mid-market commercial plane the company is thinking about building. Provided/Boeing Co.

Boeing Co. is testing potential manufacturing improvements on a demonstrator fuselage at its North Charleston campus, but the planemaker says the experiments have nothing to do with a proposed mid-market commercial plane dubbed the 797.

Lori Gunter, a Boeing spokeswoman, said the demonstrator used to test new methods of building with composite materials isn't geared toward any one commercial airplane program.

"What we learn will benefit any new program and could even lead us to improvements on existing programs," Gunter said.

The North Charleston campus currently builds the aft sections for all 787 Dreamliner wide-body jets and assembles the planes along with a Boeing factory in Everett, Wash.

Boeing hasn't said for certain whether it will build the 797, which would be designed to fill a market gap between single-aisle and wide-body jets. Officials in South Carolina and Washington are lobbying the planemaker to build the 797 in their states if the program moves forward.

"Boeing knows we are very interested and that we can be very competitive," Bobby Hitt, South Caroilna's commerce chief, told The Post and Courier.

Boeing reportedly has two versions of the 797 that it's considering, both of them single-aisle planes. The first is a 228-passenger jet with a range of 5,000 nautical miles. The second is larger, with 267 seats, and a range of 4,200 nautical miles. 

Meanwhile, there are conflicting reports over whether Boeing plans to use composite materials to build the 797 if it eventually pulls the trigger on the project. Leeham News & Comment reported that the high cost of composite materials has Boeing rethinking its manufacturing process for a new program.

However, Ihssane Mounir — Boeing's vice president of sales and marketing — said at last week's Farnborough Airshow that the company is still considering a composite structure for the plane.

Reach David Wren at 843-937-5550 or on Twitter at @David_Wren_