CFM began developing innovative solutions for tomorrow’s engines more than 15 years ago. In 2004, CFM partners Snecma and GE began to examine the development of a brand-new engine to succeed the CFM56. The following year CFM launched LEAP56™, an advanced research & technology program. In July 2008, Snecma and GE announced that CFM was officially launching a new engine, dubbed LEAP (Leading Edge Aviation Propulsion), to power the next generation of single-aisle commercial jets.
Meeting aircraft manufacturer and airline requirements
LEAP combines the best technologies from the two partners. For example, Snecma developed a fan case and blades made of a 3D woven composite using the resin transfer molding (RTM) process. These blades are significantly lighter than conventional metal blades, with greater durability and reduced maintenance needs. Snecma’s other contributions to LEAP include new alloys, such as titanium aluminide (TiAl).
The LEAP engine core was developed by GE through the eCore program. It comprises a ten-stage high-pressure compressor with a high compression ratio, driven by a two-stage high-pressure turbine. It also incorporates a second-generation lean-burn, low-emissions combustor dubbed TAPS II (Twin Annular Pre Swirl), fourth-generation 3D aerodynamic design airfoils and advanced materials and cooling technologies.
These innovative yet mature technologies make LEAP the new-generation engine of choice, ready to meet the challenges faced by aircraft manufacturers and airlines alike. When it enters service in 2016, it will give operators significant reductions in fuel consumption, noise and emissions (CO2 and NOx). Largely exceeding regulatory and environmental requirements, now and in the future, these qualities will also minimize the engine’s operating costs.
Development on schedule
After an intensive test program since 2009 on different engine modules, the first complete LEAP-1A engine started ground tests on September 4, 2013 at GE’s facility in Peebles, Ohio, two days ahead of the schedule set with Airbus three years ago. The 1A version is very similar to the 1C. On September 6, the engine reached maximum takeoff thrust. Tests by Snecma in France will start in early 2014, including vibration endurance tests.
The entire certification program for the three versions of LEAP will spread over the next three years. These tests will call on 28 engines up to certification, then 32 compliance engines for aircraft entry into service. Half of these engines will be assembled (and the development engines tested) by Snecma. A total of 60 engines will be used throughout this phase, logging some 40,000 cycles. In other words, Snecma and GE will have simulated more than 15 years of airline operations before the engine enters service.
Three LEAP versions
The LEAP-1A was chosen by Airbus in December 2010 as one of the engines offered on the new A320neo. The new airplane/engine combination should enter commercial service in 2016, after engine certification in 2015.
The LEAP-1B was selected by Boeing in August 2011 as the exclusive powerplant on the 737 MAX. Engine certification is planned in 2016, with entry into service in 2017.
The LEAP-1C was selected by Comac of China in December 2009 to power the new C919 single-aisle jetliner. Engine certification is slated for 2015.
At October 31, 2013, the three versions of the LEAP engine had totaled more than 5,600 orders and commitments.
Thrust range: 20,000 to 33,000 lb
Applications: A320neo / Boeing 737 MAX / Comac C919