United Airlines has begun consultations with Airbus and Boeing over a potential replacement for the airline’s 757 narrowbodies, United fleet vice president Ron Baur told a gathering of financiers in Phoenix at the International Society of Transport Aircraft Traders (ISTAT) conference on Tuesday.

While participating in a morning panel discussion on fleet management, Baur said the choice could depend on what Boeing eventually offers as a successor to the 757, the last of which the company built at its plant in Renton, Washington, in 2004.

Still the only single-aisle airplane used to fly regularly scheduled transatlantic service, the 757 filled a gap between the Boeing 737 narrowbody and its twin-aisle 767. That gap remains today between the 737-900ER and 787-8 Dreamliner, prompting Airbus to introduce plans for a long-range version of the A321neo that could fly as far as 4,000 nautical miles.

“When we look at the A321LR we think it’s a decent airplane,” said Baur. “But since we have the luxury of time in terms of waiting, we can see what Boeing’s going to do.”

Baur stressed that the 757s United flies across the Atlantic age well; airplanes flying shorter hops, of course, age much faster. “We have a fairly young 757 fleet, flying mainly to Europe; these are the Rolls-powered international airplanes and they’re aging pretty well, so we have time to retire that airplane,” he said. United has already begun the process of replacing 757s flying domestic services with new Boeing 737s.    

Also appearing at ISTAT, Boeing vice president of marketing Randy Tinseth told AIN that airlines have asked for an airplane bigger than the 757 and one that flies 20- to 25 percent farther, reliably from Europe to the East Coast of the U.S. without a fuel stop.

“The Airbus A321LR and a 737 Max 9 if you put a couple of [fuel] tanks in on paper look to have the same range as a 757, but in practice, if you put them to airline rules, both of them come up about 500 miles short,” he said.

The launch of any new midsize airplane would likely have to wait as long as a decade, after Boeing starts delivering the 777X, he added.

 “We’re looking at the market, not an airplane we used to deliver,” said Tinseth. “We all know there’s a space [in the marketplace], but is there a market there between the 737 and 787 and what does that market look like, what would an airplane in that market look like...We’re at that stage now where it’s about collecting information.”