CFM International comes to the Farnborough airshow with the first application for its new Leap-X engine under its belt and ready to offer more advanced versions to Boeing and Airbus for either new or re-engined versions of their respective single-aisle aircraft.

Which way will the airframers go is one of the big questions being asked at the show. “We’re ready and waiting to offer our engine,” CFM executive vice president Olivier Savin told AIN. “CFM is having talks with both with regard to both re-engining and a new aircraft. Leap-X is a committed product, so what Boeing and Airbus do is up to them. Our program is going forward.”

CFM revealed it will almost certainly build a final assembly line for the Leap X1C in China following Comac’s decision to power its C919 single-aisle airliner with the engine. “We anticipate this will be the case” said CFM executive vice-president Chaker Chahrour. He insisted, however, that the decision was not a sweetener for the engine sale. “It had absolutely nothing to do with it,” he said. “It is our own initiative to optimize the assembly process.”

The constraints of the existing Boeing and Airbus airframes mean the Leap-X offered for re-engining would be significantly different to the versions developed for an all-new aircraft. “Re-engined aircraft would be available a lot earlier, so we would expect the technology level to be somewhat lower,” said Chahrour.

Fan diameter, at around 71 inches, would, for example, be less than the optimum for re-engined aircraft than for new. The all-composite Leap-X fan provides a 10:1 bypass ratio at its maximum foreseen diameter of 76 inches, double that of the current CFM56. Coupled with further advances in core technology and with benefits of being integrated with a new airframe, it would yield a 15-percent improvement in fuel burn over the existing engine.

CFM has achieved “outstanding” results in tests of its latest development of the CFM56, the -7BE, which will become available to Boeing from mid-2011. From then on, said Chahrour, all new Boeing 737 engines will be built to this standard. As for an Airbus version of the engine, “We’re still in discussions. We hope for something this year,” he said. With continuing strong orders for both aircraft it is thought highly likely that a deal with Airbus will be reached sooner rather than later, possibly here at the Farnborough airshow.

CFM continues to reap the rewards of the pre-recession boom in narrowbody aircraft orders and expects a return to air traffic growth in 2010, which it predicts will remain stable for at least three years. “There is a strong perspective for increasing demand,” said Savin. “In the last five months we’ve seen the first signs of a return to service of parked aircraft.”

CFM believes there will be a sustained requirement for around 800 aircraft a year for the next 20 years. Most of the growth will come from emerging markets in Asia, Latin America and the Middle East.