Loren Finnerty manages more than 300 shop floor workers and engineers at GE Aerospace’s giant Asheville plant in North Carolina, where thousands of advanced composite components are produced every year for GE jet engines, such as the GE9X, as well as the LEAP engine manufactured by CFM International — a 50/50 joint company between GE and Safran Aircraft Engines of France. A manufacturing site leader, she starts work at 6 a.m. and doesn’t leave until late afternoon, a schedule that allows her to see something of all three shifts at the factory.
“It’s all about purpose,” she explains, “which is why I try to make people feel like what they’re doing matters.” She continues: “They’re not just pushing a button, but making a crucial part that goes into an engine that allows air travel to be more affordable and more sustainable.”
Finnerty’s ability to grasp fine detail and never lose sight of the bigger picture has earned her a reputation as one of GE’s shop floor gurus. She’s chalked off nearly 20 years at GE businesses, using her engineering, people, and project management skills to enhance safety, motivate teams, and boost production and efficiency everywhere she goes. “I love my job,” she says. “There’s a huge sense of satisfaction in learning how to make these parts in high volumes while using the least amount of resources.”
Finnerty’s story begins back in 2003, when she started an internship at GE Lighting in Cleveland, working in regulatory packaging, while studying mechanical engineering at Case Western Reserve University. Although she shone as bright as a bulb, she felt a little out of her element. “Packaging was kind of random for me,” she remembers. “I felt that I was probably much better at the engineering side of things.”
Her bosses agreed. Two years later, after graduating from college, Finnerty won a place with GE Lighting on the Edison Engineering Development Program, a fast track for entry-level engineers. She felt more at home, ticking off nearly seven years as a design engineer at the iconic lighting unit. While she was interested in halogen and incandescent technology, she was also developing a fascination for the production lines that the bulbs rolled off.
She started coming to grips with the orchestra of equipment, people, and processes required for the manufacturing symphony. She learned about process development, high-speed automation, project management, and factory ramp-ups. She unearthed a particular talent: harnessing her design skills to eke out additional manufacturing capability from shop floor equipment.
It wasn’t long before she transitioned from engineer to manager, overseeing capacity programs for halogen production lines and leading teams of engineers who squeezed extra output from the shop floor via conversions and refurbishments of manufacturing machines. She mastered the art of managing a program budget, organizing schedules, and integrating her production line with the factory’s other shop floors.
Her people skills came to the fore. “I was good at getting others on board, listening to them, and communicating what my team needs to run effectively,” Finnerty says. She learned that effective communication in a giant factory was a two-way street of deft talking and deep listening, and required a dash of empathy. “Why should the rest of the factory care what it is my team is working on? What might they need from us to be able to run effectively for years and years?”
Finnerty also became something of a workplace polyglot. “I’m always translating,” she says. “I might take strategy from senior leaders and put that into language that people working in that area can easily understand,” she adds. “I think: What is it that they actually care about? How’s it going to affect them six months from now?”
Finnerty was keen to spread her shop floor savvy beyond GE Lighting. In 2015, she took a role as a manufacturing engineering manager at GE Aviation in Dayton, Ohio, heading teams of engineers who were scaling up production on advanced manufacturing of turbine blades. Her work now played to all her strengths: people, cutting-edge technology, and rapidly growing shop floors.
She quickly settled in, and has performed roles as an operations manager, service manager, and plant manager at GE Aerospace over the past seven years. This included a stint at the business’s venerable Lynn facility, which was home to the first U.S. jet engine in 1942 and is now a key U.S. Department of Defense hub. Not to mention her time on the overhaul lines in Texas, overseeing the repair of used parts for the GE90, which for several years held the mantle of world’s largest and most powerful jet engine. Along the way, Finnerty has also completed no fewer than three accelerated leadership programs.
It’s been a fast track, but the experience is standing her in good stead in her current role, where she oversees output of one of the most promising technologies in the aviation industry, materials called ceramic matrix composites (CMCs). These “super ceramics” are as tough as metals, but they are also one-third as heavy and can operate at 2,400 degrees Fahrenheit — 500 degrees higher than the most advanced alloys. This combination allows engineers to design lighter components for engines that don’t need as much cooling air, generate more power, and burn less fuel. “That’s something we can all get behind,” remarks Finnerty.
The 170,000-square-foot Asheville facility was purpose-built in 2014 for CMC manufacturing, and as demand for the cutting-edge technology has soared, she has witnessed the factory floors filling up. She estimates that equipment and workstations occupied around 30% of its shop floor space in 2017. “The rest was clean white floor space with enough room for a basketball hoop,” she remembers. “Now it looks full.”
Purpose might be Finnerty’s management mantra, but her day-to-day work requires problem-solving. She employs continuous improvement, the business philosophy incorporated into lean management that is at the core of GE’s culture. “At 6 a.m. I’ll be asking how it went last night, who’s stuck, what machines are down?” she explains. “Lean is now ingrained into every aspect of the way that we work.”
But she also encourages sensible risk-taking among her team of engineers, such as trying out new production tools and techniques. “I love the fact that people feel free to come up with ideas, no matter where they work,” she says. “It’s a very curious workforce.” Nurturing an open, innovative culture on her shop floor is crucial, given the relative youth of CMC technology. “We don’t have the luxury of 30 or 40 years of experience to say, ‘Well, we did this or that before.’”
One priority is boosting the manufacturing speed of components such as shrouds to keep pace with the production ramp-up of the LEAP engine. “It’s not just volume, but variety,” she says. “We’re also getting ready for the new [families of] engines, and trialing more intricate component designs.”
There’s another big item on her list of responsibilities, which is improving access for women on GE’s shop floors. “For young female engineers, a career in lighting or aviation can seem intimidating, but if somebody has the desire and the willingness to learn, it can be a great career.”
At the Dubai Airshow this week, one of the most anticipated sights will be the Boeing 777X, Boeing’s new plane powered by the GE9X, the most powerful jet engine in the world. But thrust is just one of the engine’s many attributes. It’s also tough, and the United Arab Emirates, a hot, desert country that also happens to be the base for two of the world’s largest airlines — Emirates and Etihad Airways — is an ideal place to talk about the engine’s brawn.
The GE9X has just passed a series of 1,600 grueling dust ingestion test cycles at GE Aviation’s test site in Peebles, Ohio. GE Aviation engineers injected a stream of fine dust debris straight into a demonstration engine to simulate some of the world’s toughest flying conditions. The verdict?
“We’ve pushed this engine to the limits of what it might experience in the harshest conditions that we can imagine,” says GE9X program manager Karl Sheldon. But when they inspected the inside of the engine with a tool called the borescope, the “images of the engine looked good. Its core looks excellent, and all components are functioning as expected.”
Proving the durability in dusty conditions is just the latest drill at Peebles, where the GE9X already spent the past several years completing rigorous tests to meet strict regulatory and industry requirements. Last year, the engine received certification from the U.S. Federal Aviation Administration (FAA), a key milestone in its journey to power the twin-engine Boeing 777X family. GE Aviation is the sole engine supplier for the planes.
“These dust ingestion tests aren’t even part of any certification effort,” says Sheldon. “We’ve now put this engine through more testing than any engine in our history prior to entry into service.” According to Boeing, the 777X is expected to enter service within the next two years.
Dust can cause a slew of issues for jet engines, explains Eric Aho, GE9X systems engineering manager. Silt-sized airborne particles that sneak into an engine’s core, where the compressor, burner, and turbine are located, can wear down crucial components. This affects an engine’s efficiency and performance, meaning that the aircraft needs to burn more fuel to generate the same amount of thrust, thereby emitting more carbon dioxide.
The risks of ingesting a lot of dust is the highest during takeoff, because the first few thousand feet of altitude are relatively dense with particulate matter, Sheldon says. Takeoff is also when a plane’s engines run at full throttle, reaching temperatures over 1,000 degrees Celsius. “At that level, the dust can melt and infiltrate into the system,” Aho says. The engine’s high-pressure turbine, which is just downstream of the combustion chamber and the hottest part of the engine, is particularly susceptible to the molten debris.
To demonstrate that the GE9X could resist dust throughout the entire flight “envelope” — takeoff, cruise, and landing — GE Aviation engineers used a special rig to simulate the volume, trajectory and velocity of airborne debris that the engine might encounter in a typical journey.
GE Aviation even manufactured its own dust in partnership with scientists from GE Research Center in Niskayuna, New York. Engineers positioned the rig in front of the GE9X, and the mighty engine pulled in the specially engineered dust.
In the bowels of the engine, an array of innovations and technology keep the dust at bay. This includes a 3D-printed particle separator, which sifts out dust from the stream of air, or flow path, that cools the turbine. “Traditionally, dust blocks those cooling passages and the blades heat up, leading to durability issues,” Sheldon says.
The lining of the GE9X’s combustor and turbine shroud is also made of next-generation materials called ceramic matrix composites (CMCs), which can withstand much higher temperatures than most metals.
The GE9X engine has passed the dust test at every stage of the flight envelope. “That’s important, because the flying environment and mission will wary widely from customer to customer,” says Sheldon. He uses car drivers as an analogy: “Some people might drive their car at 4,000 RPM, but others might be driving at a completely different speed,” he says. “There’s different wear and tear on the vehicle as a result.”
At GE Aviation, engineers are always thinking about new ways to test the limits of their design, see how they do, and get new insights from the results. They are conducting 3,000 cycles of additional ground testing on the GE9X to support Extended Operations (ETOPS) approval, a certification that permits twin engine aircraft to fly routes at a prescribed distance from the nearest airport that is suitable for an emergency landing. GE Aviation anticipates ETOPS testing to conclude in the first half of 2022.
“These tests help us set a baseline going into service,” Sheldon says. “We know what the customer is going to get.”
Given these technological leaps and bounds, engineers at GE Research in Niskayuna, New York, decided a decade ago that it was time to give Santa’s sleigh a 21st-century upgrade. Seeking to optimize the present-delivery system and deliver value for stakeholders (all the good little girls and boys), they re-envisioned what the craft would look like if Santa added superefficient lighting for optimum night vision, ice-phobic coatings for the chilly North Pole air, asset intelligence tracking technology and sodium batteries. Also, Santa wore a wireless medical sensor to make sure he stayed in flying trim.
But progress stops for no man, and that includes white-bearded folklore figures, and so this year GE’s engineers went back to the drawing board to see if they could trick out Santa’s ride even further in time for the all-important Christmas Eve run.
The team started with the engines, knowing Santa would need a hypersonic rotating detonation engine (RDE) to circle the globe in record time. The hypersonic engines would propel Santa at speeds of Mach 5, or faster than 3,600 miles per hour. That would allow him to fly from New York City to Sydney in less than three hours.
But it turns out moving as fast as Santa needs to travel to circle the globe in one night requires not only the RDE but also a whole host of additional state-of-the-art technologies. GE formed a multidisciplinary team to develop them.
This sleigh needs materials to manage and withstand temperatures generated by hypersonic flying, which superheats air up to 1,800 degrees Fahrenheit — three times as hot as a backyard barbecue. The red sleigh would be glowing yellow from the heat, and the presents would be vaporized.
The engineers came up with two technologies to dissipate the heat and protect the presents, and Santa. Heat-resistant ceramic matrix composites (CMCs) would be used to build the sleigh body and jet engine blades. The CMCs can withstand temperatures in excess of 2,400 degrees Fahrenheit, while still remaining as tough as metal. Engineers also included a 3D-printed ultra-performance heat exchanger, a device that moves the heat away from the engines. It will operate at temperatures exceeding 1,650 degrees F and pressures greater than 3,600 psi. A standard scuba tank is designed to withstand just 3,000 psi. The exchanger has the added benefits of improving engine power output and reducing emissions.
To make sure Santa drinks enough milk to stay hydrated during his long ride, GE engineers suggested a sweat sensor patch. The patch, worn on the arm, will monitor Santa’s vital statistics. The team also wanted to protect Santa from data breaches, so they added digital ghost cyber protection technology to the sleigh. This advanced cyber protection platform can detect and neutralize any cyberattacks on the list of who’s been naughty and who’s been nice.
Finally, GE would embed Humble AI into the sleigh to optimize the efficiency of Santa’s travels. Engineers program the AI with an awareness of the limitations of its simulations of the real world, and give it an alternative way of proceeding that removes any uncertainty from its behavior. In other words, it gives the AI a plan B. This industrial artificial intelligence will help Santa plot his route on Christmas Eve to ensure he minimizes travel time and maximizes present delivery.
But, in the event of a sudden gust of wind or other changes in the flight conditions that the AI doesn’t recognize, it will relinquish control of the sleigh back to Santa. That ensures his flight is as safe and reliable as can be — and that Santa can deliver his presents faster than ever to children around the world.
After examining the possibility of ceramics being used in flight in 2001, scientists from the Institute for Defense Analyses starkly concluded, “There may be more pigs flying than ceramics in the future.” It’s easy to see why when you think of a coffee mug: The material is great for handling heat but breaks catastrophically when met with force.
Less than two decades later, ceramics are the most exciting part of the aviation business, as a series of scientific and manufacturing innovations have combined to create ceramic matrix composites (CMCs), advanced materials that are as tough as metals while being lighter and retaining the superior heat-handling characteristics of glass. At GE, CMC development is the culmination of $1.5 billion in investment and decades of research, which have led to crucial advances in GE engines used in military and civilian aircraft. “We are at generation one with CMCs,” says Gary Mercer, vice president of engineering at GE Aviation.
CMCs are made of silicon carbide (SiC), ceramic fibers and ceramic resin, manufactured through a sophisticated process and further enhanced with proprietary coatings. CMCs are one-third the density of metal alloys and one-third the weight, yet can handle temperatures up to 2,400 degrees Fahrenheit, when most every metallic alloy will begin to soften. This heat resistance means that turbines need less air from the flow path of a jet engine to be diverted to cool the hot-section components. By keeping more air in the flow path instead of cooling parts, the engine runs more efficiently at higher thrust.
That part directing the airflow into the hottest part of the engine — the turbine shroud — has been the first turbine component to be widely manufactured. GE has made more than 40,000, including for the best-selling LEAP turbofan that powers hundreds of single-aisle commercial jetliners. The LEAP is produced by CFM International, a 50/50 joint-venture between GE Aviation and Safran Aircraft Engines.
Engineers started seriously looking at CMCs in the 1970s with funding and encouragement from the U.S. government. By 1986, GE engineers had patented ceramic technology used in large natural gas turbines, which eventually found their way into power plants. Evolving ceramics for use in jet engines led to a decade-long effort by GE to establish America’s first fully integrated CMC supply chain, which includes a network of four interrelated GE production sites in Ohio, Delaware, North Carolina and, most recently in 2018, Alabama. The Alabama plant, located in Huntsville, is where the raw CMC fibers are made in a joint venture among GE, Safran and Nippon Carbon of Japan, an innovator in raw CMC material.
Having control over the whole supply chain means that GE can work on boosting production rates and lower costs through honing the manufacturing process. As CMCs become more integrated in GE jet engine cores, the expectation is that engine thrust will increase by 25% and fuel efficiency by 10%. Additional engine advances are expected too: Not long ago, GE engineers successfully built a military demonstrator engine that achieved the highest jet-engine temperatures ever. GE is also fine-tuning CMC-based rotating parts. The material’s characteristics also mean that CMCs will likely be essential components to spacecraft in coming years.
“As you think of the future of flight, light and hotter are two constants. With the reemergence of supersonic, hypersonic, and reusable space vehicles, it is easy to see how CMCs will add value to future propulsion and airframes alike,” says Mercer.
GE technology has been listed in the Guinness Book of World Records for years. In 1963 a locomotive powered by a pair of its J47 jet engines became the world’s fastest jet-propelled train. In 2002, the GE90-115B engine powering many Boeing 777 passenger jets locked up the title of world’s most powerful jet engine. Last June, GE’s HA gas turbine at an EDF power plant in Bouchain, France, got the nod from Guinness as the world's most efficient combined cycle power plant.
The HA turbine clocked in at 62 percent efficiency, but that record’s unlikely to remain intact for long. That’s because GE Global Research labs are applying the next generation of space-age materials called ceramic matrix composites (CMCs), new combustion technologies, and other technologies to push tomorrow’s turbine efficiency to 65 percent.
The GE labs just entered into an $8.4 million partnership with the U.S. Department of Energy (DOE) and Clemson University to develop CMC turbine nozzles for the HA gas turbine. The project is part of several others the department is supporting to improve gas turbine efficiency.
“Achieving just a 1 percent efficiency gain at the scale GE turbines work at is huge,” says John Lammas, chief technology officer for GE Power. “To put it in perspective, a 1,000-megawatt power plant using a pair of GE’s HA turbines could save $50 million on fuel over 10 years.”
CMCs are an excellent example of technology benefiting multiple GE businesses and the GE businesses learning from one another. GE’s research and development of CMCs started more than 30 years ago, also with DOE support. GE gained is first operational experience with the material on prototype parts in gas turbines. This paved the way for CMCs to make their mark in jet engines, where they provide a lighter, more heat-tolerant alternative to the metal parts they’re replacing. The lighter weight and higher heat translate into efficiency gains that can represent billions of dollars in fuel savings and lower emissions for the industry.
Building on the GE Aviation successes, and with this new DOE award, GE researchers are hoping to achieve the same benefits in GE’s gas turbines by replacing turbine nozzles made from high-grade metal alloys with CMC nozzle. But the new CMC gas turbine nozzles will be much larger and more complex, pushing the learning curve further.
But it’s not just the technology that matters. Speed is important, too. Lammas said that it used to take a decade to get a 1 percent increase in efficiency. “But with our Bouchain plant, we went from approximately 60 percent to more than 62 percent efficient in just six years,” he said. “Now, we’re looking ahead to be able to set new records in power-generation efficiency with the development of CMC parts for gas turbines,” says Don Lipkin, who works as a senior principal scientist in the Ceramics & Metallurgy group at GE Global Research.
In addition to the CMC project, the DOE also picked GE to lead a gas turbine efficiency project focused on developing an advanced combustion part to more optimally manage the mix of fuel and air in the combustion process. This is another critical step in achieving higher turbine efficiency.
Correa and his team at GE say that a new class of materials called ceramic matrix composites (CMCs) is set to revolutionize everything from power generation to aviation, and allow engineers to build much more powerful and efficient jet engines before the end of the decade. “This is a huge play for us,” he says.
A pair of the first commercial jet engines with CMCs inside debuted on Tuesday at the Farnborough Internal Airshow in England, when they powered Boeing's next-generation 737 MAX jet.
Correa has an inside view. He leads the CMC program at GE Aviation, which is investing $200 million to build two new CMC factories in Huntsville, Alabama.
The Rocket City factories —a nickname tied to Huntsville's role in launching Americans to space —will be supplying raw material to the first American CMC plant, which GE opened last year in Asheville, North Carolina. The company also already operates two CMC “lean labs” in Newark, Delaware, and Cincinnati, Ohio, that are looking for new applications for the materials and new ways to make them. “Opening the new plants in Alabama is a key step in building up the supply chain we need to make CMC parts in large volumes,” Correa says.
GE scientists have been working on CMCs for two decades. These “super ceramics” are as tough as metals, but they are also one-third as heavy and can operate at 2,400 degrees Fahrenheit—500 degrees higher than the most advanced alloys. This combination allows engineers to design lighter components for engines that don’t need as much cooling air, generate more power and burn less fuel.
Correa and his team believe that CMCs could allow designers to increase jet engine thrust by 25 percent and decrease fuel consumption by 10 percent by 2020.
While these numbers are pregnant with promise, CMCs have been extremely difficult to mass-produce. Until fairly recently, their use was limited to the space industry and fighter jet exhaust systems.
GE’s first applications were less lofty, but also more practical. Starting in 2000, GE’s Oil & Gas business tested CMCs inside a 2-megawatt gas turbine in Florence, Italy. By the middle of the decade, turbines with CMC shrouds—special parts directing the flow of air into the hottest parts of the machines—were running for thousands of hours without a hitch.
GE’s aviation business picked up the technology in 2007 and started looking for jet engine applications at its lean laboratory in Delaware. (This is an example of the vaunted “GE Store”—the transfer or technology and knowledge between GE businesses.)
GE Aviation first used the material for CMC shrouds in the hot section of its F136 fighter jet engine, but their application quickly spread. Static CMC parts are already flying inside the LEAP on the Boeing 737 MAX, Airbus A320neo and Airbus A321neo jets. The LEAP's maker, CFM International—a 50/50 joint venture between GE Aviation and Safran Aircraft Engines of France—has received more than 10,800 orders and commitments for the engines valued at more than $150 billion (list price).
In 2015, GE started testing CMC components in a GEnx engine – the type used by many Boeing Dreamliners – to mature the technology for its latest large engine: the GE9X. Now on a test stand at GE's boot camp for jet engines in Peebles, Ohio, the GE9X engine is the largest jet engine ever built with 11 feet in fan diameter, and it is capable of producing of titanic air compression (60:1, if you ask)—arguably the highest ever in the history of aviation. “We expect a 10-fold increase in demand for CMCs when these and other engines take off by the end of 2020,” Correa says.
Correa’s team is far from finished, though. Earlier last year, it tested the first spinning parts inside the latest-generation ADVENT adaptive cycle engine, a demonstrator engine for the U.S. Department of Defense. GE Aviation just received a $1 billion contract to develop the engine further. The machine which has 45,000 pounds of thrust could one day also power the F-35 Joint Strike Fighter. "This is extremely important to us," says Jean Lydon-Rodgers, GE Aviation's vice president and general manager for military affairs.
GE researchers have now started replacing rotating metal components with CMCs. This is a big deal because shedding their weight by two-thirds will produce a knock-on effect by lowering the centrifugal force inside the engine. For example, it will allow designers to reduce the size of the engine’s main shaft and cut engine weight further.
GE makes CMCs from tiny silicon carbide fibers embedded in a silicon carbide matrix. The fibers are five times as thin than a human hair and coated with a “very highly proprietary coating,” Correa says. The result is “tough like a metal [but] not brittle like a ceramic,” he says.
GE first started producing the fibers in Japan in 2012, after it formed a joint venture company, NGS Advanced Fibers Co., with Nippon Carbon and Safran. NGS owns one-half of the company and the GE and Safran split the rest. One of the new Huntsville plants will be the first such facility of its kind in the U.S. It will supply GE businesses and also the U.S. Department of Defense. The second facility will take the fiber and make a highly-proprietary CMC tape for use by the GE CMC plant in Asheville.
The other two components of GE’s CMC ecosystem—the lean labs in Ohio and Delaware—are already looking for new applications for the materials and new fabrication methods, respectively.
Before long, you maybe flying to China in a plane powered by ceramics.
Starting on Feb. 1, Emirates launched the world’s longest passenger flight between Dubai and Panama City. A westbound Boeing 777-200LR powered by a pair of GE90 engines covers the 8,950 miles that separates them on a single tank of gas in 17 hours and 35 minutes. But that record may soon topple. In January, Qatar Airways announced plans to launch a 9,034-mile flight lasting 18 hours and 30 minutes between Doha and Auckland in New Zealand. That route would use an Airbus A350 plane, which has GE composite components in its wings. Finally, United launched the longest flight originating at a U.S. airport between San Francisco and Singapore in June. It's the world’s longest scheduled route flown by a GEnx-powered Boeing’s 787 Dreamliner. The eastbound leg lasts 15h 30min and the westbound trip back clocks in at 16h 20min.
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These new efficiency benchmarks have their origin in the oil shock. NASA, in particular, began a quest to develop an energy-efficient engine for commercial aircraft known as the E3 (E-cubed) program. GE joined early on and developed a new generation of high-bypass turbofan engines starting with the GE90. It has since added the GEnx for the Dreamliner and 747-8, and the GE9X, which is currently in development.
To reduce weight, GE equipped the engines with light, carbon-fiber composite fan blades. To this day no other engine maker has engines with composite fan blades in service today. (The design for the GE90 was so fetching that one blade is now on display at New York’s Museum of Modern Art.). “This was a huge, expensive and risky project,” says Shridhar Nath, who leads the composites lab at GE Global Research. “We planned to replace titanium with what is essentially plastic. We were starting from scratch and we did not know how carbon fiber blades would respond to rain, hail, snow and sand, and the large forces inside the engine.”
But it paid off. “The engines essentially opened the globe up to incredibly efficient, twin-powered, wide-body planes,” says David Joyce, president and CEO of GE Aviation.
The latest engine in the GE family, the GE9X, will power Boeing’s next-generation 777X long-haul jets. Lightweight carbon composites allowed engineers to design an 11-foot fan that can suck a maelstrom of 8,000 pounds of air per second inside the engine. The air will flow into the combustor, where it meets parts made from ceramic matrix composites (CMCs), another breakthrough material developed by GE scientists.
Carbon fiber composites work with cold air at the front of the engine. But CMCs, which were originally developed for massive gas turbines for power plants, operate in the engine’s hot section, at temperatures where even metals grow soft. The extra heat gained by the ceramics gives the engine more energy to work with and makes it more efficient.
CMCs also have twice the strength and just a third of the weight of their metal counterparts. This allows designers to make parts from them thinner and much lighter, further reducing the weight of the engine. Says GE researcher Krishnan Luthra, who spent two decades developing the material: “I thought it would be the Holy Grail if we could make it work.”