<img src="https://spectrum.ieee.org/media-library/color-photo-of-a-small-gray-airplane-with-a-man-standing-beside-it-and-plugging-in-a-charging-cable.jpg?id=68517917&width=1245&height=700&coordinates=0%2C141%2C0%2C141"/><br/><br/><p><strong>In the cockpit </strong>of Beta Technologies’ Alia CX300, pilot <a href="https://linkedin.com/in/christopher-caputo-80a470157" rel="noopener noreferrer" target="_blank">Chris Caputo</a> steers onto Runway 33 at <a href="https://btv.aero/" rel="noopener noreferrer" target="_blank">Patrick Leahy Burlington International Airport</a> in Vermont. Cleared for takeoff, he releases the brakes and nudges the throttle forward.</p><div class="rm-embed embed-media"><iframe height="110px" id="noa-web-audio-player" src="https://embed-player.newsoveraudio.com/v4?key=q5m19e&id=https://spectrum.ieee.org/beta-technologies-electric-aircraft&bgColor=F5F5F5&color=1b1b1c&playColor=1b1b1c&progressBgColor=F5F5F5&progressBorderColor=bdbbbb&titleColor=1b1b1c&timeColor=1b1b1c&speedColor=1b1b1c&noaLinkColor=556B7D&noaLinkHighlightColor=FF4B00&feedbackButton=false" style="border: none" width="100%"></iframe></div><p>At the back of the aircraft, the five-blade pusher propeller snaps awake, and the Alia bolts forward. There’s no shriek of a turbofan spooling up, no shudder of a piston engine, and no wait for thrust. Just the low hum of an electric motor and a shove of instant acceleration.</p><p>Within a few seconds, we’re at 85 knots (almost 160 kilometers per hour), and Caputo rotates the nose upward. The runway drops abruptly away as we climb. Gaining speed and altitude, we head northwest over Lake Champlain. Through the wraparound canopy, I watch the hunched shoulders of Vermont’s Green Mountains shrink under the right wing, with New York’s taller Adirondacks to the left.</p><p>Caputo, a former Air Force fighter pilot, flicks the control stick hard left, then right. Despite its 15-meter wingspan, the Alia feels snappy, its fly-by-wire system automatically coordinating aileron and rudder inputs. The machine, he says, is much simpler to manage than the <a href="https://cessna.txtav.com/en/piston/cessna-skylane" rel="noopener noreferrer" target="_blank"> Cessna 182</a> I flew around Australia in my student-pilot days.</p><p>What’s more, our half-hour flight in the Alia will consume only about US $9 worth of electricity. The same flight in a comparable <a href="https://cessna.txtav.com/en/turboprop/caravan" rel="noopener noreferrer" target="_blank">Cessna 208 Caravan</a> would burn roughly 25 to 30 gallons of Jet A fuel, costing about $210 to $255 at press time. “Even at full throttle, we’re not burning any fuel up here,” says Caputo, as he takes the Alia into a sweeping left turn and heads south over the lake. “We’re not polluting the environment. [There’s] no noise pollution.”</p><p class="shortcode-media shortcode-media-rebelmouse-image"> <img alt="Color photo of three men building the body of a small airplane that\u2019s sitting on a yellow platform." class="rm-shortcode" data-rm-shortcode-id="36d5d7f2584471d10504b70a2bf1a164" data-rm-shortcode-name="rebelmouse-image" id="2d9ac" loading="lazy" src="https://spectrum.ieee.org/media-library/color-photo-of-three-men-building-the-body-of-a-small-airplane-that-u2019s-sitting-on-a-yellow-platform.jpg?id=68518111&width=980"/><small class="image-media media-caption" placeholder="Add Photo Caption...">At Beta’s South Burlington, Vt., facility, workers assemble the body of an Alia A250. The company says it has an order and option-to-buy backlog of nearly 1,000 aircraft.</small><small class="image-media media-photo-credit" placeholder="Add Photo Credit...">Beta Technologies</small></p><p><span>This ride is happening during an unusually lively time for electric aviation. The promise of lower operating costs and cleaner flight has pushed electric aircraft from a fringe experiment to one of the aviation industry’s most closely watched frontiers. After years of renderings, prototypes, and overly optimistic timetables, companies are now flying full-size aircraft, submitting hardware to regulators for certification, building factories, and testing routes with prospective customers.</span></p><p>Among the top three U.S. developers of electric planes, <a href="https://www.archer.com/" target="_blank">Archer Aviation</a> and <a href="https://www.jobyaviation.com/" target="_blank">Joby Aviation</a> are concentrating on piloted vertical-takeoff-and-landing air taxis, otherwise known as eVTOLs. <a href="https://beta.team/" target="_blank">Beta Technologies</a> is taking a broader—and in some ways more innovative—path into the market. Rather than betting first on air taxis, Beta is looking to enter electric aviation through short-haul freight planes that use conventional runways, fed by an open charging network that’s designed to make electric aircraft—both Beta’s and its competitors’—part of a working transportation system.</p><p>To that end, the company is developing two variants of its Alia airframe: the runway-based CX300 I’m flying in and the <a href="https://www.beta.team/aircraft" target="_blank">A250</a>, which adds four lift propellers for vertical takeoff and landing. Beta says its test pilots have flown the Alia family more than 300,000 kilometers, including doing multiple U.S. crossings and overseas demonstrations. The company claims an order and option-to-buy backlog of 991 aircraft.</p><p class="ieee-inbody-related"><strong>RELATED: </strong><a href="https://spectrum.ieee.org/kyle-clark-profile/kyle-clark" target="_self">From Hockey Enforcer to High-Flying eVTOL CEO</a></p><p><span>“We’re taking a pragmatic stepwise approach for both certification and market entry,” says Beta’s CEO and founder </span><a href="https://investors.beta.team/governance/leadership-team" target="_blank">Kyle Clark</a><span>. “We’re ready to go today with medical and cargo aircraft that fly from airport to airport.” Next up, he says, will be passenger aircraft with conventional takeoff and landing, followed by cargo eVTOLs, and finally passenger eVTOLs.</span></p><h2>Reducing the Risk of FAA Certification</h2><p>Beta’s 17,500-square-meter production facility sits beside the Burlington airport and looks more like a giant sunlit workshop than a conventional airplane factory. Geothermal heat pumps help heat and cool the structure. The roof will eventually hold a megawatt of solar panels. On the floor, technicians make composite structures and join aircraft sections beneath American and Pride flags.</p><h3></h3><br/><table border-collapse:="" border:="" collapse;="" none;="" style="white-space: unset;" width="100%"><tbody><!-- Row 1: Header / Title --><tr><td style="padding: 24px 16px 18px 16px; border-bottom: 0px solid #000; background-color: #000000; color: #ffffff;"><p style="font-size: 24px; line-height: 1.2;"><strong>3 Competing Paths to Electric Aviation</strong></p><p>The top three U.S. electric-aircraft makers are taking different approaches to the same challenge: how to make short-hop flight cleaner, quieter, and commercially useful.</p></td></tr><!-- Row 2: Joby Image --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #DFD5C1"><p class="shortcode-media shortcode-media-rebelmouse-image"><span class="shortcode-media-positioning"><a class="shortcode-media-lightbox__toggle shortcode-media-controls__button material-icons" style="background: gray;" title="Select for lightbox">aspect_ratio</a></span><img alt="Illustration of a small airplane viewed from above with 6 propellers." class="rm-shortcode rm-lazyloadable-image" data-rm-shortcode-id="55e60872c085035d08f5578f863d56dc" data-rm-shortcode-name="rebelmouse-image" height="537" id="f3a2b" lazy-loadable="true" src="https://spectrum.ieee.org/media-library/image.png?id=68518506&width=980" width="976"/></p><style class="image-media media-photo-credit">Chris Philpot</style></td></tr><!-- Row 3: Joby Text --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #DFD5C1"><a href="https://www.jobyaviation.com/" target="_blank"><strong>Joby Aviation</strong></a>’s piloted, four-passenger S4 aircraft has six tilting propellers to provide both vertical lift and cruise propulsion. It’s optimized for fast, quiet air-taxi service. The company is also working on <a href="https://spectrum.ieee.org/joby-air-taxi-2676635230" target="_self">hydrogen fuel cells for longer-range transport</a>. Joby says the S4 is in the final stage of the Federal Aviation Administration’s certification process and has flown trials in <a href="https://www.jobyaviation.com/news/dubai-air-taxi-network-takes-flight-joby-completes-landmark-flight-and-announces-next-vertiport" target="_blank">Dubai</a>, <a href="https://ir.jobyaviation.com/news-events/press-releases/detail/181/joby-brings-electric-air-taxis-to-new-york-city-in" target="_blank">New York</a>, and <a href="https://www.jobyaviation.com/news/joby-launches-eipp-flights-in-texas" target="_blank">Texas</a>.</td></tr><!-- Row 4: Archer Image (Placeholder) --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #E9E3D6"><p class="shortcode-media shortcode-media-rebelmouse-image"><img alt="Illustration of a small airplane with 12 propellers, not all of which are visible." class="rm-shortcode rm-lazyloadable-image" data-rm-shortcode-id="484e33c9e0069dd459fc2ac7579752ea" data-rm-shortcode-name="rebelmouse-image" height="549" id="02b51" lazy-loadable="true" src="https://spectrum.ieee.org/media-library/image.png?id=68529864&width=980" width="976"/></p><style class="image-media media-photo-credit">Chris Philpot</style><!-- Insert Beta Image Shortcode Here --></td></tr><!-- Row 5: Archer Text --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #E9E3D6"><a href="https://archer.com/" target="_blank"><strong>Archer Aviation</strong></a>’s piloted, four-passenger Midnight has 12 propellers—six tilting rotors and six stationary rotors. The aircraft, which Archer has been testing in both vertical and conventional takeoffs and landings, is aimed at air-taxi service in urban areas. The company says Midnight is in Phase 4 of the FAA certification process and has completed trial flights.</td></tr><!-- Row 6: Beta Image (Placeholder) --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #DFD5C1"><p class="shortcode-media shortcode-media-rebelmouse-image"><img alt="Illustration of two small airplanes, the one in the foreground having propellers and the one in the background having no propellers." class="rm-shortcode rm-lazyloadable-image" data-rm-shortcode-id="5e545723288d28d78b4f5f8d2835f2d8" data-rm-shortcode-name="rebelmouse-image" height="549" id="16c3b" lazy-loadable="true" src="https://spectrum.ieee.org/media-library/image.png?id=68529944&width=980" width="976"/></p><style class="image-media media-photo-credit">Chris Philpot</style><!-- Insert Beta Image Shortcode Here --></td></tr><!-- Row 7: Beta Text --><tr><td style="padding: 10px; border: 0px solid #ccc; background-color: #DFD5C1"><a href="https://beta.team/" target="_blank"><strong>Beta Technologies</strong></a>’ piloted Alia aircraft comes in <a href="https://beta.team/aircraft" target="_blank">two flavors</a>: The A250 eVTOL has separate vertical-lift rotors and a rear cruise propeller, while the CX300 is a conventional-takeoff fixed-wing plane. The two models use the same pusher motor, battery pack, flight control computer, and fixed-pitch propeller. The company is initially focusing on cargo and medical transport, regional logistics, and airport-to-airport operations, with passenger service later. Beta expects <a href="https://www.flyingmag.com/beta-technologies-electric-aircraft-media-day/" target="_blank">FAA certification</a> for the CX300 in 2027 and for the A250 a year later.</td></tr></tbody></table><h3></h3><br/><p><a href="https://spectrum.ieee.org/kyle-clark-profile/kyle-clark" target="_self">Kyle Clark</a>, a native of Vermont, founded Beta in 2017 to realize his long-held dream of building a hybrid-electric aircraft. (For his bachelor’s thesis at Harvard University, he designed a flight-control system for such an aircraft.) <a href="https://achievement.org/achiever/martine-rothblatt-ph-d/" rel="noopener noreferrer" target="_blank">Martine Rothblatt</a>, CEO of the biotech company <a href="https://www.unither.com/home" rel="noopener noreferrer" target="_blank">United Therapeutics</a> and cofounder of <a href="https://www.siriusxm.com/" rel="noopener noreferrer" target="_blank">SiriusXM </a>satellite radio, invested $48 million in Beta to fund its first prototype, with the eventual goal of using the aircraft to transport organs for transplantation.</p><p>The company has kept much of its design and manufacturing in-house, partly because the pieces are closely coupled and partly because suitable aviation components didn’t exist when development began. Vertical integration gives Beta’s engineers control over the interfaces and any failure data. But it also means the company must be competent at several businesses simultaneously: airframes, electric motors, inverters, batteries, software, chargers, and aircraft production.</p><p>The production line can build both the fixed-wing CX300 and the vertical-lift A250, which share the same fuselage, wings, pusher motor (for horizontal propulsion), batteries, avionics, and much of the tooling. This results in some one-size-fits-all decisions: The CX300’s twin booms, which connect the wing to the tail surfaces, look superfluous until you see the A250’s four lift propellers mounted on similar structures.</p><p>On the CX300, those booms add weight and drag even though they serve no lift function. But the trade-off—a simpler overall design—is part of Beta’s central strategy: Rather than applying for FAA certification for the more novel and complex eVTOL A250, with its multiple lift systems and transitions between hover and wing-borne flight, the company is bringing the runway version forward first. It’s certifying the motor, batteries, fly-by-wire controls, and much of the airframe in the simpler aircraft; it will then reuse evidence and manufacturing experience when it certifies the A250.</p><p>The other big reason to start with the CX300 is logistical: The United States has more than 5,000 public-use airports, so the CX300 can operate from infrastructure that already exists. The cargo and medical flights that the aircraft will initially tackle offer tightly defined missions in which lower energy and maintenance costs matter more than cabin amenities. Hence the company’s decision to leave cabin air-conditioning off the CX300, at least for now. “Things that don’t exist on an airplane don’t weigh anything,” Clark says. “They can’t break. You don’t have to service them…. You don’t have to certify them.”</p><p><span></span>“This strategy, at the beginning, was seen as a failure of their VTOL,” says analyst <a href="https://www.linkedin.com/in/sergiocecutta/?isSelfProfile=false" target="_blank">Sergio Cecutta</a>, a managing partner at SMG Consulting. “But I think a lot of people were very myopic. It was a way for [Beta] to break up the certification in two pieces, and so they have retired a lot of the risk. [A majority] of the [CX300’s] parts are shared with the VTOL, and that means that a lot of the documentation for certification can be easily reused on the VTOL side when that certification starts.”</p><h2>How Redundancy Enhances Safety</h2><p>A decade and a half after electric cars began making significant inroads into the automotive market, electric airplane technology is advancing rapidly. In some ways, an electric car has more complicated power-engineering requirements than an electric aircraft. An electric car’s power demands change constantly, while an electric aircraft operates in a narrower set of power regimes: takeoff, level flight, and descent.</p><p>But if your car’s drivetrain fails, you can just pull over to the side of the road. That’s not an option for a pilot 1,000 meters up. The hurdle isn’t that electric motors are inherently fragile; it’s that aviation safety standards are extraordinarily demanding. Catastrophic failure conditions generally must be held to roughly one chance in a billion flight hours or less.</p><h3></h3><br/><img alt="Color photo taken from above showing a gray and white small airplane in a high-ceilinged space, being worked on by people on ladders." class="rm-shortcode" data-rm-shortcode-id="7d631a484d9dc840ba3c5ee8aa65a1f2" data-rm-shortcode-name="rebelmouse-image" id="9810c" loading="lazy" src="https://spectrum.ieee.org/media-library/color-photo-taken-from-above-showing-a-gray-and-white-small-airplane-in-a-high-ceilinged-space-being-worked-on-by-people-on-lad.jpg?id=68518124&width=980"><h3></h3><br/><p>Because individual electrical components cannot meet that standard on their own, electric aircraft rely on layered redundancy: duplicate power paths, independent inverters, fault isolation, monitoring, and backup capacity. Each layer helps close the safety gap, but each also adds weight and complexity.</p><p>To close the reliability gap and satisfy regulators who have little experience with electric aircraft, Beta engineers have built redundancy into <a href="https://beta.team/motor" rel="noopener noreferrer" target="_blank">the motor</a> itself. When I visit the company’s motor shop, technicians are assembling the H500A pusher motor, which splits up critical components like the inverters and stator sections.</p><p>“You could lose an entire half of the system, and it would still function the same,” says <a href="https://www.flyingmag.com/beta-technologies-electric-aircraft-media-day/" rel="noopener noreferrer" target="_blank">Adam Lowe</a>, Beta’s flight operations lead.</p><p>The H500A’s broad diameter gives the magnetic forces greater leverage, producing high torque at low rotational speed, a useful trait when turning large propellers. The H500A weighs about 75 kilograms and produces about 640 kilowatts of power. The motor achieves 97.5 percent efficiency, based on internal testing; typical conventional turboprops have an efficiency range of 25 to 35 percent.</p><p>Beta had aimed to have its motor certified in the first half of 2026, a deadline that passed without a public announcement. Although the company’s certification strategy is aimed at streamlining the process, getting clearance to fly from the <a href="https://www.faa.gov/" target="_blank">Federal Aviation Administration</a> is probably still its biggest obstacle. For Beta, and any company trying to bring an electric aircraft into service, the FAA must sign off first on the propeller, then the motor, then the aircraft. After that, the manufacturer must pursue a production certificate from the FAA, proving that the company can build the same approved aircraft again and again, with the right tools, records, inspections, quality controls, supplier oversight, training, calibration, and parts tracking.</p><h3></h3><br/><span class="rm-shortcode" data-rm-shortcode-id="854a9dbb41782e37cf2b174a42adcea8" style="display:block;position:relative;padding-top:56.25%;"><iframe frameborder="0" height="auto" lazy-loadable="true" scrolling="no" src="https://www.youtube.com/embed/ohwqxK0BCtM?rel=0" style="position:absolute;top:0;left:0;width:100%;height:100%;" width="100%"></iframe></span><h3></h3><br/><p>Beta has found a narrow on-ramp to get the A250 flying before full certification. Under the <a href="https://www.faa.gov/newsroom/future-aviation-here-trumps-transportation-secretary-sean-p-duffy-and-faa-unveil-eight" target="_blank">FAA’s eVTOL Integration Pilot Program</a>, companies and public agencies can run FAA-supervised, real-world trials to test how advanced air-mobility aircraft might operate in the national airspace. For Beta, that included July flights across a Virginia-to-Maryland corridor carrying, among other things, a manufactured transplantable organ in a medical containment system. Beta has also been chosen for six other FAA-backed trials.</p><p>For the fixed-wing Alia CX300, customer trials are moving in parallel. In March, Beta’s CX300 successfully <a href="https://investors.beta.team/news-events/press-releases/detail/113/loganair-adds-beta-technologies-alia-ctol-aircraft-to-its-fleet-following-successful-demonstrations-in-united-kingdom" target="_blank">completed 23 flights</a> over 10 days on Loganair routes linking six Scottish cities. The airline has since signed a <a href="https://www.loganair.co.uk/news/loganair-adds-beta-technologies-alia-ctol-aircraft-to-its-fleet-following-successful-demonstrations-in-united-kingdom/" rel="noopener noreferrer" target="_blank">term sheet</a> for five Beta aircraft, with options for five more and service expected to start in 2029.</p><h2></h2><h2>Innovation in eVTOLs</h2><p>Beta is pushing so hard for the A250 because the case for electric flight gets even more interesting with vertical-lift aircraft. Helicopters and other VTOLs have a less orderly life than fixed-wing planes do. They must hover, sidestep, turn in place, settle, climb, and hold themselves in the air by main force. But conventional helicopters are built around a rotor speed that varies only a few percent because the engine, transmission, and rotor system are all designed around one narrow operating point.</p><p>“One of the dreams of vertical flight has been to vary the rotor rpm,” says<a href="https://aero.umd.edu/clark/faculty/525/Anubhav-Datta" rel="noopener noreferrer" target="_blank"> </a><a href="https://aero.umd.edu/clark/faculty/19/Anubhav-Datta" rel="noopener noreferrer" target="_blank">Anubhav Datta</a>, an aerospace engineering professor at the University of Maryland, College Park, who studies electric propulsion and vertical flight. Electric motors, he argues, have advanced enough to make that practical. A rotor that can slow down or speed up as conditions change can waste less energy, make less noise, and better match the odd assortment of tasks that vertical flight demands.</p><p>Electric propulsion also lets designers break up the work with multiple motors. The weight of an electric motor is tied closely to its torque. If you spread that torque among several motors, each of the motors can shrink, meaning that their combined weight is less than would be needed for one big engine. This is one reason why so many electric aircraft designs appear to have sprouted propellers wherever an engineer found a place to put one.</p><p>There is a downside to using multiple smaller motors: If one of the motors quits, the rotor it’s driving has little stored energy compared to the inertia in a conventional helicopter’s one large rotor. This inertia can come in handy if the engine dies, because the rotor will continue to spin and allow the pilot to descend under control, in an emergency technique known as autorotation.</p><h3>Beta Technologies, Made in Vermont</h3><br/><img alt="Large group of employees gathered in an aircraft hangar with planes in the background." class="rm-shortcode" data-rm-shortcode-id="b32dbd0a462cdc08f4c34062ac724dc0" data-rm-shortcode-name="rebelmouse-image" id="5f01c" loading="lazy" src="https://spectrum.ieee.org/media-library/large-group-of-employees-gathered-in-an-aircraft-hangar-with-planes-in-the-background.jpg?id=68530775&width=980"><p>According to Beta Technologies founder and CEO Kyle Clark, his native Vermont—known more for its maple syrup and outdoorsy lifestyle than its technological achievements—is a big part of the secret to Beta’s success at attracting talent. “The recruiting strategy is this: You find anybody who has vacationed in Vermont or went to school here. And you say, ‘You can actually live here and have a high-paying job in a mission-driven business, doing something that you care about with great people.’ ” The company currently employs about 1,500 people, most of them in South Burlington, Vt., and is actively hiring for its engineering, manufacturing, software, flight operations, and commercial teams.</p><p>As befits an aviation company, Beta offers flying lessons for all employees—a perk that is intended to give engineers, software developers, pilots, and mechanics a common language. The company also operates a health clinic for employees and their families and is building a day care center. Those programs have an idealistic Vermont flavor that is shaped by Clark and his wife, <a href="https://investors.beta.team/governance/leadership-team" target="_blank">Katie Clark</a>, who is Beta’s head of brand, creative, culture and spaces. But they also serve a practical purpose: attracting and retaining the best people in a small labor market. <em>—T.C.</em></p></img></img><p>Electric-aircraft makers compensate with redundant motors and electrical channels, but most leading designs also have wings to allow gliding. In Beta’s A250, that means that if all else fails, the pilot still has a shot at reaching a suitable landing spot.</p><p>That helps explain the convergence in today’s eVTOL designs. <a href="https://www.jobyaviation.com/aircraft/" target="_blank">Joby Aviation</a>’s S4 uses six propellers that tilt between lift and cruise. <a href="https://www.archer.com/aircraft" target="_blank">Archer Aviation’s Midnight</a> has six tilting propellers and six dedicated lift props. Beta’s A250 keeps its four lift propellers horizontal and uses a separate pusher motor for forward flight.</p><h2>Beta’s Approach to Batteries</h2><p><span><span>In Beta’s home state of Vermont, the electricity produced in the state comes almost entirely from renewable sources. Of course, electric aviation’s climate advantage depends not only on how clean the power grid is, but on how efficiently the aircraft uses energy. The turbines in conventional jet engines are marvelous machines, but they throw away a lot of energy as heat. Plus they need to carry the hardware to manage that heat—inlets, ducts, radiators, oil coolers—and the drag that comes with pulling air through all of it. </span></span></p><p class="shortcode-media shortcode-media-rebelmouse-image rm-float-left rm-resized-container rm-resized-container-25" data-rm-resized-container="25%" style="float: left;"> <img alt="A photo showing a bearded white man wearing a helmet and piloting an aircraft" class="rm-shortcode" data-rm-shortcode-id="de9c1c1df73c31dfba408a119d8b6f6e" data-rm-shortcode-name="rebelmouse-image" id="c7d60" loading="lazy" src="https://spectrum.ieee.org/media-library/a-photo-showing-a-bearded-white-man-wearing-a-helmet-and-piloting-an-aircraft.jpg?id=68518211&width=980"/></p><p class="shortcode-media shortcode-media-rebelmouse-image rm-float-left rm-resized-container rm-resized-container-25" data-rm-resized-container="25%" style="float: left;"> <img alt=" A photo showing a small white plane flying above a shoreline" class="rm-shortcode" data-rm-shortcode-id="51aab9f28f2a85e3bd828a40cb59c27e" data-rm-shortcode-name="rebelmouse-image" id="514ad" loading="lazy" src="https://spectrum.ieee.org/media-library/a-photo-showing-a-small-white-plane-flying-above-a-shoreline.jpg?id=68518209&width=980"/><small class="image-media media-caption" placeholder="Add Photo Caption...">Kyle Clark [in cockpit], founder and CEO of Beta Technologies, pilots the company’s Alia CX300, an electric plane that Beta expects to receive FAA certification in 2027. Clark began designing a hybrid electric plane while still in college.</small><small class="image-media media-photo-credit" placeholder="Add Photo Credit...">Beta Technologies</small></p><p><span><span></span>By contrast, an electric design, with no combustion, gearbox, or oil circuits, avoids much of that energy burden. The result is an aircraft that is more than twice as “slippery” in terms of its lift-to-drag ratio. Batteries will never come close to the fuel density of petroleum fuels. But because electric drivetrains are much more efficient than combustion engines, a battery doesn’t necessarily need to match the energy density of petroleum fuel to be useful.</span></p><p>While the motors on an electric aircraft provide the drama at takeoff and landing, the batteries set nearly every boundary: the range, payload, charge time, cooling load, reserve energy, and, ultimately, useful life. For now, the hardest limit on electric aviation is not imagination, software, or even motors. It is the stubborn weight of stored energy.</p><p>“One thing you notice about [electric] airplanes is that they are all small,” says Cecutta, the aviation analyst. “They are not small because someone has done a market study and decided that is the optimal size. They are small because you cannot make them big. This limitation is from the batteries.”</p><p>In a conventional aircraft, fuel accounts for a significant percentage of the takeoff weight. But that weight gradually disappears during flight. In an electric plane, the battery packs also account for a lot of the weight; in Beta’s CX300, they’re close to half the aircraft’s mass. But a drained battery at landing weighs the same as a fully charged one at takeoff. That means the rest of the aircraft must be light enough to lift a power source that never gets lighter, yet strong enough to endure vibration, turbulence, hard landings, and years of fatigue. The more engineers push to save weight, Datta notes, the more flexible the airframe becomes, making the wings and other structures more prone to bending, twisting, and vibration. In that sense, the battery problem becomes a structural problem, too.</p><p>Beta’s CX300 carries five liquid-cooled <a href="https://beta.team/battery" target="_blank">battery packs</a> of about 45 kilowatt-hours each, giving the aircraft roughly 225 kWh of rated capacity, though not all of that may be usable in flight. Each pack weighs 255 kg and contains 2,772 cylindrical cells. Altogether, about 14,000 cells sit beneath the occupied cabin, each one a tiny storehouse of energy, heat, and potential trouble.</p><p>The burden of the battery explains much of what I see elsewhere in Beta’s aircraft: the 15-meter wingspan, the composite structure, and the almost doctrinal effort to leave out every piece of hardware and creature comfort that’s not essential to the mission. The CX300 even does without flaps, which most aircraft use to generate extra lift at low speeds, so it must take off and land unusually fast for an aircraft of its size.</p><p>On Beta’s battery line, commercially supplied standard 21-millimeter-diameter, 70-mm-long cells are tested and assembled. Cells become modules, modules become subpacks, and eleven subpacks become a 45-kWh pack. Cooling plates manage heat during normal operation, while passive barriers and electrical isolation are designed to contain the ugly edge cases that Beta’s testing process intentionally triggers.</p><p>The modular design of the packs will give Beta’s planes a path to better batteries as the cells and battery chemistry improve. Caputo tells me that the company is already evaluating higher-density cells at its battery testing facility in nearby St. Albans, Vt. More watt-hours per kilogram could eventually mean more range, more payload, or both.</p><h2>Beta Technologies’ Electric Ecosystem</h2><p>What sets Beta Technologies apart from its competitors is the breadth of its ambitions: It’s not just building electric aircraft. It’s also cultivating a broader ecosystem to nurture the growth of electric aviation.</p><p>For instance, Beta intends its motor business to extend beyond its own aircraft. The company has delivered lift motors for <a href="https://www.eveairmobility.com/" target="_blank">Eve Air Mobility</a>’s proof-of-concept aircraft and has a contract to supply up to <a href="https://www.eveairmobility.com/eve-air-mobility-selects-beta-technologies-as-pusher-motor-supplier/" target="_blank">$1 billion in pusher motors</a> as Eve’s program develops. In addition, Beta is selling flight-control computers and software to <a href="https://www.horizonaircraft.com/" target="_blank">Horizon Aircraft</a>. It is also producing propulsion systems for the military, as well as the <a href="https://beta.team/defense" target="_blank">MV250</a>, a hybrid-electric autonomous aircraft for defense missions.</p><p class="shortcode-media shortcode-media-rebelmouse-image"> <img alt='Color photo of two cubelike structures, one labeled "charge" and the other labeled "thermal."' class="rm-shortcode" data-rm-shortcode-id="94f447b0439786defc0c96e106c7ed75" data-rm-shortcode-name="rebelmouse-image" id="61648" loading="lazy" src="https://spectrum.ieee.org/media-library/color-photo-of-two-cubelike-structures-one-labeled-charge-and-the-other-labeled-thermal.jpg?id=68518063&width=980"/><small class="image-media media-caption" placeholder="Add Photo Caption...">Beta’s fast-charging stations [left] have been installed at 138 locations. The thermal-management station [right] keeps the battery from overheating during charging. The company uses the open-standard Combined Charging System (CCS) so that other aircraft can use its chargers. </small><small class="image-media media-photo-credit" placeholder="Add Photo Credit...">Beta Technologies</small></p><p>Further evidence of Beta’s far-ranging plans is visible near the battery line in the South Burlington facility, where workers are readying a few of the company’s 1.5-meter-tall <a href="https://beta.team/charge-cube" target="_blank">Charge Cubes</a> for shipping. Intended for installation at airports, each cube takes 480-volt AC from the grid and can deliver up to 320 kW at as much as 1,000 volts DC. According to Beta, charging either model of its Alia aircraft takes about 35 minutes, from the minimum charge required under visual flight rules to full state. A separate thermal-management cube circulates water-glycol coolant through the aircraft to keep the batteries from overheating during charging.</p><p>The charge cubes use the Combined Charging System <a href="https://www.charin.global/technology/ccs-specification/" target="_blank">(CCS)</a>, an open standard increasingly shared across the electric transportation industry. Beta’s strategy resembles Tesla’s decision to treat <a href="https://www.tesla.com/supercharger" target="_blank">charging</a> as part of the vehicle business, with one important difference: Beta is courting other aircraft makers, airports, and operators to use its technology. Archer,<a href="https://www.signatureaviation.com/" target="_blank"> </a><a href="https://www.atlanticaviation.com/" target="_blank">Atlantic Aviation</a>, <a href="https://www.signatureaviation.com/" target="_blank">Signature Aviation</a>,<a href="https://www.atlanticaviation.com/" target="_blank"> </a>and government agencies have purchased or installed Beta’s charging equipment. As of October, Beta has 138 fast-charge locations, with additional sites in permitting or construction.</p><p>For charging beyond the fixed network, Beta offers a wheeled 40-kW <a href="https://beta.team/mini-cube?hsCtaAttrib=184705145623" target="_blank">Mini Cube</a> and a 65-kW Mini Cube+ that can ride inside an Alia and plug into more modest electrical service. The Mini Cube can also charge cars, buses, and trucks—any vehicle that uses the CCS standard.</p><p>Back above Lake Champlain, the CX300 levels off, and the motor recedes to a faint hum. Then Caputo switches it off, and there’s nothing but the rush of wind around the canopy. The aircraft glides on its long wings while the coasting propeller turns the motor into a generator, feeding about 9 kW back to the battery.</p><p>Then we turn to the east and slip into the landing queue behind a National Guard C-130 Hercules, and Caputo powers and slides the throttle forward. The motor springs to life again, pushing the airplane, and perhaps aviation itself, into the future. <span class="ieee-end-mark"></span></p>
Reference: https://ift.tt/4h5rMvq
