Airlines have told the planemaker they are interested in something about 20 percent bigger than its out-of-production 757 and able to fly further, putting it beyond the reach of the latest A321LR single-aisle offering from rival Airbus, he said.
Speaking in an interview ahead of the Paris Airshow, John Wojick, senior vice president for global sales and marketing at Boeing Commercial Airplanes, said airlines were looking for an jetliner able to seat about 240 people with greater comfort, but just as efficiently as the smaller 737 workhorse.
"That is the secret sauce. If we can find a way to do that, we think we would have a really effective plane in the marketplace," Wojick told Reuters.
The last 757 was delivered in 2005, but remains popular with U.S. airlines because of its range and performance, while its larger contemporary, the 767, is being replaced by the 787 Dreamliner.
Many 757s will soon come up for replacement.
"We sold over 1,000 757s and several hundred 767-200s so it would make sense that (the market) was at least that big," Wojick said, adding there would also be growth on top of that.
The market is "certainly more than 1,000," he said.
Wojick declined to comment on how many orders Boeing expects to announce at this week's air show, but said it would be "tracking toward" the full-year target by the end of June.
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