Flights servicing islands are an attractive target for early electrification, given their short-haul routes.

With that in mind, Hawthorne, California-based electric aviation startup Ampaire, Inc. plans to demonstrate a retrofitted hybrid-electric plane on a commercial route on the Hawaiian island of Maui later this year.

In partnership with Mokulele Airlines, and with backing from the Elemental Excelerator, a Honolulu-based nonprofit startup accelerator, Ampaire plans to launch regular test flights between airports in Kahului and Hana, Maui.

For now, Ampaire is focused on hybrid-electric flight. The company’s Electric EEL is a twin-engine Cessna 337 Skymaster retrofitted to include one conventional combustion engine and one Ampaire electric motor. The plane will have a range of about 200 miles, with reserves, according to Ampaire product manager Brice Nzeukou.

“We see the most practical step to bring the compelling benefits of electric aviation — lower operating costs, lower maintenance costs — to the market by starting with hybrid-electric first versus going full electric,” Nzeukou told Greentech Media.

Ampaire conducted its first public test flight above Camarillo, California on June 6. According to Nzeukou, the prototype Electric EEL performed as expected during its initial test flights.

“We’ve learned that the aircraft is able to recover safely. Our design targets have been validated. That’s been one of the major takeaways: The safety of the aircraft is exactly what we thought it would be,” he said.

Ampaire expects to receive a supplemental type certificate (STC) from the Federal Aviation Administration for the Electric EEL by the end of 2021.

Demonstrating hybrid-electric flight in Maui

Elemental Excelerator selected Ampaire as one of its portfolio companies, which receive up to $1 million in funding, in its 2019 cohort. For the team at Elemental Excelerator, Ampaire’s Electric EEL was the right plane at the right time for Hawaii.

“We targeted electric aircraft companies in our last round because our analysis indicated it was the right time for the market,” Ramsay Siegal, managing director of Elemental Excelerator, wrote in an email.

“With the expectation that regulatory frameworks governing electric air travel will come into focus globally, we wanted to support a near-term solution to satisfy flight-time requirements, charging infrastructure, and other commercialization elements so they are ready to scale the moment the FAA landscape enables them to do so,” she said.

The fact that Ampaire aims for the Electric EEL to be FAA-certified by 2021 was a deciding factor in Elemental Excelerator’s support.

“We were specifically excited about Ampaire because of their approach of retrofitting existing airplanes, rather than building an entirely new electric aircraft that could be years away. Ampaire's partnership with Mokulele Airlines is going to help make commercial electric flights a reality far faster than many people think,” said Siegal.

Siegal went on, “Electrifying the aviation industry can put a massive dent in global carbon emissions, but it's an extremely thorny problem. And it's especially pressing in Hawaii, where the aviation sector accounts for nearly one-third of petroleum usage.”

Elemental Excelerator is helping to fund the entire Maui demonstration, said Ampaire’s Nzeukou, from material purchases to operating costs.

“Without their funding, this project would have never happened,” he said.

Goal: An all-electric OEM

Nzeukou said Ampaire is committed to transitioning to all-electric planes over time. The company views all-electric flight as a technology maturation issue.

With billions of dollars being invested in battery technology globally, he said, “We’re hoping to see the fruits of those investments realized: higher energy density, different chemistries coming out and production costs going down.”

“As soon as it is practical and compelling and really viable for our business case and for our customers, that’s when we would consider doing an all-electric version."

The company sees its Electric EEL, the retrofitted Cessna 337 Skymaster, as a first step in a process that culminates in Ampaire selling planes designed to be all-electric from the start. The next step, according to Ampaire’s CEO Kevin Noertker, is likely the development of either a hybrid-electric or all-electric nine- to 19-passenger commuter or cargo aircraft.

Eventually, Ampaire will focus on its new-build, nine-passenger, all-electric Tailwind concept plane.

“We want to sell our planes under the Ampaire brand,” Nzeukou said. “Our primary focus, and our main strategy, is to be an aircraft [original equipment manufacturer], and to retrofit planes for the time being and eventually go into new-build, clean-sheet aircraft.”

“However,” he went on, “there are opportunities to license our technology to other aircraft OEMs that may want to be able to offer the benefits of electric propulsion to their customers.”

Last week, Ampaire began accepting letters of intent for the Electric EEL from general aviation pilots. The two versions of the plane will seat four or six passengers and be outfitted with a 215-horsepower (hp), 160-kilowatt electric motor and either a Continental IO-550 310-hp piston engine or a Continental CD-300 Jet A diesel 300-hp engine.

According to Ampaire, either version “will be cost-competitive with comparable current production piston twins.”

Ampaire is among the startups jostling to be first to bring hybrid-electric or all-electric planes to market. GTM reported in April that British Columbia’s Harbour Air is partnering with electric propulsion startup magniX to retrofit its entire 40-strong fleet of conventional seaplanes into an all-electric fleet.

Passengers could board Harbour Air’s first all-electric commercial flight by the end of 2021 or early 2022.