As the push for sustainability within business aviation grows, so too do efforts by startup and established firms to offer all-electric fixed-wing aircraft. Though not anywhere near as voluminous as the seemingly hundreds of proposed eVTOL offerings and designs, a smaller group of companies are proposing more traditional business aircraft with electric powerplants.
They include Pipistrel in Slovenia, which last year certified in Europe an electrically powered light trainer; Ampaire in California, which in 2019 first flew a Cessna 337 Skymaster converted to hybrid-electric propulsion that it calls the Electric EEL; and Magnix and AeroTec, which last May completed the first flight of a Cessna 208B Grand Caravan with an all-electric propulsion system.
In addition, two other proposed electric airplanes—one hybrid, the other all-electric—are on the drawing board that could mark the emergence of battery-powered business aircraft: the Daher-Airbus-Safran EcoPulse and Bye Aerospace eFlyer 800. While these two models and others that are sure to follow don’t represent an immediate threat to the turbofan-powered product lineup from traditional business aircraft OEMs, these electric aircraft pioneers bear watching by them. “If you’re them, I think you have to keep an eye out on it,” Teal Group v-p of analysis Richard Aboulafia told AIN.
In reality, it may be several years before all-electric aircraft become a viable option for operators and serious competition to business aircraft OEMs, independent business aviation analyst Brian Foley explained to AIN. Business jet-size electric aircraft "are probably a little further down the path,” he said.
Nevertheless, with flight shaming on the rise and the desire by corporate clients to demonstrate their commitment to leaving a smaller carbon footprint to shareholders and the public alike, it’s clear to analysts like Foley that the push to move away from fossil-fuel-powered aircraft is here to stay. “It’s creeping up,” Foley said, and “eventually it will touch the corporate aircraft sector.”
In 2019, Daher, Safran, and Airbus announced an effort to develop the EcoPulse, a distributed propulsion hybrid aircraft demonstrator backed by the French government that is based on a TBM airframe with six electric thrusters, three each mounted on the leading edge and tip of the TBM’s wing. The project has completed its preliminary design review and is entering the assembly and integration phase at Daher this year.
Meanwhile, Safran has finalized the technical configuration of the EcoPulse's electric thrusters that will be fitted with 50-kW Engineus electric motors, as well as integrated electronics and patented air cooling. DUC Hélices will supply the propellers. For Safran, the next step will be to deliver an electric thruster to Airbus for wind tunnel and endurance testing as a precursor to qualification for EcoPulse’s first flight, which is scheduled for 2022.
“With this demonstrator, Daher intends to develop the key architectural principles for future hybrid aircraft,” said Daher chief technology officer Pascal Laguerre. “The project reaffirms our commitment, as a general aviation manufacturer with our Kodiak and TBM product lines, to more efficient and eco-responsible aviation.”
Recently, Bye Aerospace, which is working toward FAA Part 23 type certification for its two-seat eFlyer 2 model, unveiled plans for the eFlyer 800, an all-electric aircraft with seating for seven passengers and two pilots on flights of up to 500 nm at 320 ktas. Powered by a pair of Safran's Engineus electric motors, the eFlyer would compete with existing turboprops such as the Beechcraft King Air 260 and Daher TBM 910.
“The time is right, the technology readiness is right at hand, the FAA regulatory process is becoming much better understood, and the program's progressing through to the normal category FAR Part 23 amendment 64 certification,” Bye Aerospace CEO and founder George Bye told AIN. “All of that is the building blocks for the eFlyer 2 and the eFlyer 4, and then the 4 to the eFlyer 800.”
Even with less than a third of the range of the King Air 260 and TBM 910, Bye believes the eFlyer 800 will more than effectively compete with those and other business turboprops. He argues that the range of the eFlyer 800 is consistent with the distance a turboprop flies on a typical mission and at a lower cost.
“The 500-nautical-mile number is a key number for this category of aircraft,” Bye said. "Ninety percent of the turboprop missions, 90 percent, take place in 440 nautical miles or less. I mean, if you can accomplish 90 percent of your missions for one-fifth of the operating costs on a brand new, high-tech, no CO2, no-noise aircraft, bravo. Bravo.”
Foley believes the path to electric business aircraft the size of light, midsize and super-midsize jets is a ways away simply because an electrically powered aircraft the size of a Cessna Citation Longitude or Bombardier Challenger 350 would require enough batteries with “nothing short of a Mack truck in weight.”
“But fast-forwarding to when that day arrives, where there’s some kind of change in business jet propulsion, it could likely begin with some kind of hybrid set up first where you might have the traditional turbine jet-A powered engine for doing the heavy lifting, like the takeoffs and getting up to altitude, and then you could potentially switch over to some form of electric and cruise at least,” Foley added.
Neither Foley nor Aboulafia thinks the current lack of participation in electrically powered business aircraft by the major business aviation OEMs means they will ultimately be left behind in coming to market with such an aircraft. Aboulafia believes that once the demand for such aircraft is there, OEMs could simply acquire the intellectual property necessary to fielding such an aircraft, given that there are a lot of players in the electric powerplant space, albeit for largely eVTOL designs.
Foley noted that new propulsion and battery technology will follow the same path in business aviation that it always has. “Generally, in aviation, the technology that’s available to one manufacturer is available for the next, too. So maybe we’re waiting for the battery suppliers and the electric powerplant suppliers to come to them with some solutions. There will be a first adopter but the second will be right behind.”
But not all business aviation OEMs are sitting on the sidelines, however. The parent company of Textron Aviation announced in late March the launch of an eAviation division headed by former Textron Aviation senior v-p of global sales and flight operations Rob Scholl. According to Scholl, the division will bring together the work being done across Textron’s fixed-wing and vertical-lift businesses around emerging electric technologies.
“eAviation is looking at all options when it comes to the development of electric, fixed-wing as well as VTOL aircraft for urban air mobility,” Scholl told AIN. “Electric propulsion is just one such technology and we will continue to evaluate its potential role with our future aircraft development plans. The role of eAviation is to drive collaboration on a variety of new technologies and capabilities across the Textron enterprise. We continue to evaluate new aircraft technologies to determine how to best serve our customers and operators.”