Engine manufacturer CFM International reports that the Leap series of turbofans under development for the new Airbus A320neo, Boeing 737 Max and Comac C919 narrowbodies is performing as planned since full engine testing began last month. “I’m proud and really happy to tell you that the engine is running smoothly,” Chaker Chahrour, CFM executive vice president, told reporters in a teleconference on October 16. “This engine wants to run.”
CFM, the 50-50 joint venture of GE Aviation and France’s Snecma, started testing the first full Leap turbofan, a Leap-1A designed for the Airbus A320neo, two days ahead of schedule on September 4. “We quickly got to 50-percent power on that same day, and then got to full power a few hours later after we did all the break-in runs that we needed to do on the engine,” Chahrour said. “In fact, we achieved more than the 30,000-pound full rated thrust of the engine within 48 hours of [starting the testing].”
Chahrour said the joint venture had run the complete Leap engine for 174 total hours, during which it logged 269 test cycles and 164 starts, at GE’s outdoor test facility in Peebles, Ohio.
CFM promises the Leap engine will provide a 15-percent improvement in specific fuel consumption and an equivalent reduction in carbon emissions compared with its CFM56-7BE, which powers the Boeing 737NG. Chahrour said the major technological innovations that support that target, which include composite fan blades and fan case, titanium aluminide alloy low-pressure turbine blades, lean-burning combustor and ceramic matrix composite (CMC) engine shrouds, are performing well.
Chahrour ventured that the Leap engine will generate 1- to 2-percent better fuel efficiency than Pratt & Whitney’s competing PurePower PW1100G turbofan, a claim that Pratt & Whitney later contested in published reports. Airbus offers that engine for the A320neo. The Leap-1B and Leap-1C engines, respectively, will appear exclusively on the 737 Max and Comac C919.
The start of flight-testing on the Leap-1C engine for the Comac C919 on GE’s Boeing 747 testbed represents the program’s next major milestone, scheduled for May next year. Also next year, CFM plans to perform icing, ingestion and “torture” testing of the engine, during which it will run it at maximum speed and exhaust gas temperature for extended periods. The company plans to begin testing the first full Leap-1B engine for the 737 Max at midyear. Fifteen developmental engines will undergo testing next year, executives said.
Plans call for the overall engine certification program, encompassing all Leap variants, to consist of 28 CFM developmental ground- and flight-test engines and 32 “compliance” flight-test engines for delivery to Airbus, Boeing and Comac.
Airbus plans to deliver the first Leap-powered A320neo in 2016. Cedric Goubet, CFM executive vice president representing Safran, said the company aims to produce 1,700 Leap engines annually within three years, or at the start of 2019. That rate would exceed the current CFM56 series production rate by 200 engines annually.
Airlines have placed orders for more than 5,000 Leap engines. Jean-Paul Ebanga, CFM president and CEO, said the company has received orders for 2,196 Leap and CFM56 engines as of September, surpassing the orders for 1,972 in all of last year. Total Leap orders this year stand at 1,102 compared with 1,192 for all of last year.