CFM unveils new next generation turbofan engine that promises 16 percent reduction in CO2 emissions
LEAP-X TAPS II combustor sector testing (photo: CFM)
Mon 14 July 2008 – As the 2008 Farnborough Air Show gets under way, engine manufacturer CFM International (CFM) has formally launched LEAP-X, an entirely new turbofan engine to power future replacements of narrowbody aircraft like the Airbus A320 and Boeing 737. CFM claims new technology will reduce fuel burn and CO2 emissions by 16 percent, NOx emissions by 60 percent and noise by between 10-15dB compared to its current CFM56 Tech Insertion engines.
The company says a full demonstrator engine is scheduled to run in 2012 and could be certified by 2016. However, its entry into service is dependent on progress by Airbus and Boeing in developing successors to their current narrowbody generations.
The launch coincides with the signing of an agreement by the two joint owners of CFM, General Electric Company (US) and Snecma, part of the French SAFRAN Group, to extend the partnership that started in 1974 to the year 2040.
“Our industry is in the midst of perhaps the most challenging times we have ever faced,” said Jean-Paul Herteman, CEO of SAFRAN Group. “In the early 1970s, the GE/Snecma partnership brought the benefits of high-bypass turbofan technology to reduce fuel burn by 20% compared to the low-bypass engines they replaced, while introducing a new standard in reliability. We are now in a position to bring that same magnitude of improvement to the industry for the next 30 years.”
David Joyce, President and CEO of GE Aviation, commented: “Together, through the LEAP-X engine, we are bringing an advanced suite of revolutionary technologies to market that will take the next generation of single-aisle aircraft to a whole new level of fuel efficiency, while also reducing NOx emissions, carbon emissions and noise. We understand the pressures the airlines are under.”
LEAP-X benefits from developments in composite materials technology, so that fan blades will be stronger, more durable and lighter, with the result that the number of blades can be reduced by 25% compared to the current CFM56-7B narrowbody engine. Further use of new composites within the LEAP-X engine could bring a total 1,000-pound (454kg) weight benefit per aircraft, claims CFM. A new TAPS II combustor is expected to achieve reductions of 60% in NOx emissions compared to ICAO CAEP/6 regulations that took effect earlier this year.
“When we launched the LEAP56 technology development programme in 2005, fuel was at $1.30 a gallon,” said Eric Bachelet, President and CEO of CFM International. “Today, airlines are paying nearly $4.00 a gallon. Our customers are hurting and we are responding. LEAP56 is the single largest investment in technology in our history. We have set aggressive targets for LEAP-X and the technology plan is in place to achieve them.”
CFM admit, though, the LEAP-X engine falls short of ACARE industry targets on CO2 and NOx emissions for new aircraft entering service in 2020, which look for reductions in engine CO2 emissions of 20% and NOx emissions by 80%.
However, the engine manufacturer is already building on LEAP and is currently developing open rotor technology that could lead to even better improvements in fuel burn, and therefore CO2 emissions, with reductions of 26% compared to current engines, exceeding ACARE. One of the trade-offs with open rotor engines is increased noise levels and CFM is working on developing pitch change technology to address the issue, but is uncommitted as to when such a revolutionary engine could become a reality.
CFM is supporting a biofuel test programme with Continental Airlines, in which one of the airline’s Boeing 737 aircraft powered by CFM56-7B engines will perform a biofuels demonstration flight in 2009. CFM and parent GE are currently working to identify a suitable biofuel source that can be produced in suitable quantities to support extensive engine ground testing prior to the flight. CFM says it is evaluating second-generation, non-food or water competing alternative fuels produced from biomass.
Along with GE, CFM is participating in a number of emissions-focused initiatives, including the US Climate Action Partnership. It is also involved in several alternative fuels research programmes, including the French CALIN and European Alpha-Bird programmes, dedicated to researching third-generation molecules for biofuels, as well as the European DREAM programme, tasked with demonstrating the ability to operate aircraft with existing alternative fuels.
Last year, CFM completed an initial ground test of a CFM56-7B engine using a biofuel blend consisting of 30% vegetable oil methyl ester blended with 70% conventional Jet-A1 fuel that aimed to validate the operation of one of its engines using biomass without having to make any technical changes.
