Meet Dr. Dale Carlson, the jet engine cardiologist. Every day, Dr. Carlson and his team of engineers strap their two-ton patients to a massive rig inside GE Aviation’s plant in Evendale, Ohio, attach probes and sensors, and put their cores through a rigorous workout. “Just like the heart is the most important organ in your body, the key piece in a jet engine is the core,” says Carlson, who received his doctorate in aeronautics and astronautics from MIT and serves as manager of advanced programs at GE’s aviation unit. “It’s where the fuel is burned and thus has the greatest impact on overall engine efficiency.” GE spends more than $1 billion on jet engine R&D, which includes the testing of cores. “It’s a very complex process with an enormous amount of data gathering,” Carlson says. “But over the last 20 years it helped us reduce fuel burn by one percent year after year.”
The Doctor Will See You Now: Dale Carlson runs tests on jet engine cores for CFM’s advanced LEAP engines. The cores are 15 percent more efficient that existing GE models, saving customers millions of dollars.
That will soon change. Engineers at GE Aviation built a brand new jet engine ticker called eCore that helps cut fuel use by 15 percent in one swoop, compared to current GE models. That means millions in savings for customers. The new heart will power CFM International’s new line of advanced LEAP jet engines for next-generation single-aisle aircraft like Boeing 737 MAX and Airbus A320neo. “The trick is to give the customer the same great performance, reliability and low maintenance costs, but keep boosting the engine efficiency,” Carlson says.
Just like the human heart, engine core has several key moving parts. The compressor squeezes the air to titanic pressures, the combustor blends in fuel and burns it, and the high pressure turbine then harvests the energy of the hot gas and powers the airplane. The eCore doubles the compressor pressure ratio of the previous CFM56 jet engine core to 22 to 1, which is the best in its class, and translates to higher engine efficiency. “Every time you try to compress the air that way, it fights back,” Carlson says. “If you don’t get this right, the air flow separates and introduces inefficiencies. The compressor is burping back at you. We call that stall.” Stall makes the engine lose the thrust that propels the plane .
GE engineers also used new technologies and materials like lean burning and heat-resistant ceramic matrix composites (CMCs) to perfect the core and prevent stalls, improve burn, and save fuel. “These are extremely tough, durable, engine-ready materials in which we have extensive experience,” Carlson says.
The LEAP, which is part of GE’s ecomagination portfolio, is the next step in the evolution of the CFM56 engine, the world’s best-selling jet engine. There are over 22,000 CFM56 engines in service today. They accrue one million flight-hours every 8.5 days. “What eCORE means for the LEAP is that we are now going to deliver additional 15 percent better fuel performance against the CFM56 baseline with the same maintenance costs and reliability, which is world class,” Carlson says. “Because of our innovation, we don’t need to use complex systems such as gearboxes and other tricks.”
Customers have noticed. LEAP orders and commitments reached $47.5 billion in 2011, from customers like Southwest Airlines, Virgin America, and Qantas. CFM has received more than 450 LEAP orders and commitments valued at billions more at the Farnborough International Airshow currently under way in England.