When Boeing’s Vice President and general manager of Product Development Mike Sinnett shares new concept aircraft, media are usually quick to depict them as THE potential new aircraft from Seattle. That’s why Boeing during Monday’s presentation on the Future of Flight and sustainable aviation was quick to explain that three concepts are just that - concepts. Cascade will help Boeing to shape its future aircraft. Sinnett, who has presented countless Boeing concepts in his career, showed what a potential hybrid, electric, or hydrogen-powered could look like. Which could be a 787-sized conventional-looking airliner (hydrogen), a high-wing turboprop with four electric motors (hybrid), and a small, business-jet like aircraft (electric). They could all emerge from demonstrator programs like the current ecoDemonstrator, the Transconic Truss-Braced Wing demonstrator to be developed together with NASA, the Hybrid Propulsion demonstrator with General Electric, and NASA, and the battery-powered Wisk eVTOL, which is on static display in Farnborough. From the current product portfolio via demonstrators through the potential concepts: the roadmap of Boeing towards zero-emission aircraft. (Boeing) Sinnet, Chief Sustainability Officer Chris Raymond, and Brian Yutko, Boeing chief engineer and vice president of Sustainability and Future Mobility, were all teased to mention when these concepts could become a reality. But they weren’t prepared to go into specifics of years and dates. In fact, the joint message during the presentation was that more time is needed (by Boeing, at least…) to figure out what is the best, most realistic, and feasible technology available to get aviation to zero emissions by 2050, as the aviation industry has set itself as a target. Boeing is using a specific tool for that and has gone public with it in Farnborough. Called Cascade, it is a digital toolbox in which input produces different scenarios and visualizes the effects they have on emissions. It looks at fleet renewal (-17 percent emissions), future aircraft (-7.4 percent), operational efficiencies (-6.1 percent), sustainable aviation fuels of SAF (dependent on the blend or pure -26 to -36 percent). Together, carbon emissions could be reduced by 44 percent in the example, Yutko showed. A slide from the Boeing presentation on Cascade, showing how the input of different data impacts net CO2 emissions. (Boeing) When it comes to adding renewable energy like electric and hydrogen to the picture, things start getting is a bit more blurred. Is it black, grey, or green electricity, grey, blue, or green hydrogen? What is available in which quantities and in which regions of the world? “You can see there is a tipping point in which hydrogen airplanes make the systems worse or better. What is interesting of these tools, is the ability for us to go into a particular region and sit down with particular stakeholders and talk about potential grids or the grid outlook they have”, said Yutko. He continued: “The ultimate goal is how these different technology interventions get us to net zero. What we are building is the ability to pick a particular airplane, insert that into the fleet, and chose which introduction date you’d like to have and which grid you would like to have over time and being able to model scenarios for 2050.” In all scenarios, SAF is a key factor: “SAFs are required, we can’t let ourselves into scenarios that this is an either/or, that it is SAF or these things. If we wait, we will wait too long. Our view is that SAF is required, no matter what happens with those other technologies”, said Chris Raymond, who added that aviation will need 77 times more SAF in 2050 to meet requirements. But aviation will also need hydrogen, dependent on renewable electricity. “As the hydrogen source becomes more renewable because we are making it more often with electrolyzes and renewable energy grids, this is a spectrum that is driving great innovation.” A careful approach to new fuels But Boeing is taking a careful approach to new fuels, in particular hydrogen, as it already said last year in its sustainability report. Whereas Airbus has firmly opted for hydrogen as the energy source for its ZEROe next-generation of aircraft for the mid-30s, Boeing is careful. As Mike Sinnett said: “We would never move to the next thing until we know for sure that it can be as safe or safer than what we have today. Fuel is a really important piece of this. Before we move to the next fuel type, we need to know as much as possible to ensure that it is as safe as what we have today. What I love about the Cascade tool is that it allows you to start exploring what design choices will have, and what impacts from a climate perspective. Because it isn’t just about emissions from the tailpipe, it is about total climate impact.” Developing a new generation of sustainable aircraft will have the next generation of engineers busy until 2050, says Brian Yutko. (Richard Schuurman) “Every airplane design we have ever done and designs that will follow, start with: do the physics work? You can’t pick an answer until you know that. Is there enough room for fuel, can you contain the fuel safely? Once we are convinced that the physics work, we ask: can it be both safe and certifiable?”, Sinnett explained. “Then there is potentially an aircraft that comes back at the end of that. But then you have to ask what the value proposition is. What is the cost of the fuel versus the cost of operations, can you make it work, and will it make a meaningful difference? Will it increase or decrease the amount of climate impact.” Intersection of new technologies Cascade will help Boeing determine where the intersection is of all the new technologies that it is developing before it will commit to a new aircraft concept. Yutko acknowledged that meeting the targets is ambitious. “There will be a generation of engineers whose life goal is to get this done. This doesn’t happen overnight, there are 27.5 years between now and 2050. (…) We have an incredible research portfolio at Boeing, so we are going to execute a substantial amount of research and technology programs related to battery-electric systems, related to fuel cell systems, and related to all the enabling and underlying technologies. We will also be conceiving potential future demonstrators, potential future products someday may be.” “We are still learning what is the right thing to do. Before you move, you have to move what is the right thing to do. And our industry doesn’t yet know what is the right thing to do”, said Mike Sinnett. “Hydrogen is a good example: until we understand the impact of hydrogen on contrails at altitude and the climate impact of these contrails, we aren’t sure hydrogen is the right answer yet. But we are doing the homework to make sure that we understand. Cascade will help us with that.”
