Electra.aero on June 7 revealed the configuration of its first commercial product — a hybrid electric short take-off and landing (eSTOL) vehicle designed to operate out of take-off and landing sites “shorter than a soccer field.” The eight-seat aircraft will be able to land and depart at speeds below 30 miles per hour (48 kilometers per hour) and cruise at up to 200 mph (320 km/h), the company said.
The vehicle is powered by a hybrid-electric propulsion system incorporating eight electric motors and a small turbogenerator that allows the aircraft to recharge while in flight and have a higher load factor for cargo and passengers. STOL performance is enhanced through the use of “blown lift” technology, in which the electric motor-driven propellers blow air over the entire span of the wing and its flaps.
Electra.aero was founded by John Langford, best known as the founder of Aurora Flight Sciences, which was acquired by Boeing in 2017. It is one of a growing number of eSTOL challengers in the urban and regional air mobility markets, whose aircraft could make up in range and performance what they lack in VTOL capability. For example, Electra said its new configuration will be able to fly as far as 500 miles (800 km), while eVTOL developers Joby Aviation and Lilium are targeting maximum ranges of around 150 miles (240 km) at launch.
On June 8, another eSTOL developer, Airflow, announced a $200 million order from Ravn Alaska for up to 50 of its aircraft, which are targeted to enter service in 2025.
“As we evaluated the effectiveness of eVTOL technology, we always ended up with reduced payload and range performance,” Diana Siegel, Electra’s director of strategy, told eVTOL.com. Siegel has previous experience working on eVTOL aircraft at Aurora Flight Sciences, and “we didn’t feel this would serve the market well enough,” she said.
Siegel said Electra’s hybrid eSTOL model will allow for more flexible operations on both longer and shorter routes because it does not rely on a large charging infrastructure. This is a clear upside to the company’s hybrid propulsion system, even though it isn’t emissions-free.
However, Siegel said Electra plans to integrate a fully electric propulsion system in the future when battery technology capable of meeting the team’s performance specifications is available. “Sustainability is absolutely at the core of our mission,” she emphasized.
Federal Aviation Administration certification of the aircraft is targeted for 2026 under the agency’s Part 23 rules for small airplanes. Electra is testing the propulsion system this summer, and plans to start full-scale flight testing next year, Seigel said.