(Bloomberg) -- Boeing Co.’s boss knocked down speculation that the company might unveil an all-new airplane this decade to counter the Airbus SE airplane that’s dominating sales of large, single-aisle models.

Dave Calhoun, the US planemaker’s chief executive officer, said Wednesday he doesn’t see breakthrough technology looming that would justify a multibillion-dollar investment in jetliners intended to last 50 years or longer. Boeing’s customers wouldn’t sign up for a plane that isn’t at least 20% more efficient than current models, and there’s no engine on the horizon that could deliver such fuel savings this decade, Calhoun told investors and analysts in Seattle.

“There is nothing proven on the propulsion side of the house,” Calhoun said.

The CEO also squelched talk that Boeing is working on a so-called “clean sheet” design similar to the midrange jetliner that he canceled soon after taking the top job in 2020. “They’re not typically invented to fill a niche or some of the product gap you have relative to portfolios,” Calhoun said of all-new jet programs.

Airbus has claimed about 60% of the narrowbody market due to the success of its A321neo, which carries 200-plus passengers and has emerged as the heir to Boeing’s out-of-production 757 jetliner. While US planemaker doesn’t have an offering that matches the Airbus jet’s range and passenger capacity, Calhoun indicated he isn’t angling for the 50-50 split that the two manufacturers traditionally shared.

“I want to get to stable,” Calhoun said. “Whether we are tied, one, or two in that market is not going to be the be-all and end-all.”

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