Boeing has refined the timeline for a final decision on re-engining the 737 or opting for a clean-sheet replacement of its narrowbody family.
Jim Albaugh, chief executive of Boeing Commercial Airplanes, says that a decision will be made "probably this fall".
Joining Albaugh at a recent investor meeting, Boeing chief executive Jim McNerney added that increasing cashflow once the company begins 787 deliveries will enable Boeing to "ride high for a while" heading towards 737 and 777 development.
The decision scheduled for later this year is set against the backdrop of sold-out delivery slots for its existing 737 family and a planned production rate increase from 31.5 to 34 aircraft a month scheduled for early 2012.
McNerney acknowledges that increasing narrowbody production rates on both sides of the Atlantic are driven, in part, by new programmes such as the Bombardier CSeries.
"If we don't continue to ramp up, if Airbus doesn't continue to ramp up, my view is we're going to drive many of our existing customers to buy some of those new airplanes," he says. "And I think one of the ways that we protect where we are is to make sure that we have the capacity to address what their demands are, and we're working that very hard."