Mokulele ready to test hybrid aircraft between Kahului, Hana

Prototype plane to land on Maui this fall

Ampaire, a California tech startup, plans to launch test flights of this hybrid electric aircraft from Kahului to Hana starting this fall. The Cessna 337 Skymaster has been retrofitted with an electric motor. Photo courtesy of Brice Nzeukou

A California startup plans to begin test flights of a hybrid electric aircraft between Kahului and Hana later this year, technology that could eventually prove a “game changer” for interisland carriers like Mokulele Airlines.

Ampaire is bringing the prototype plane to Maui this fall and will partner with Mokulele on a series of test flights over a period of six months, Mokulele President Rob McKinney said Thursday.

“I think we would be the ideal launch customer for this technology with the length of route that we fly and the conditions that we fly in,” McKinney said. “We don’t have to contend with super cold weather.”

Ampaire started in 2016 with a focus on retrofitting aircraft to fly on electric power, a less expensive alternative to building them from scratch. The company’s research on Maui will be funded by Elemental Excelerator, a Hawaii nonprofit that supports startups with innovative ideas in energy, water, food and agriculture and mobility. Every year, the nonprofit finds 15 to 20 companies that fit its mission and provides them with up to $1 million each. Ampaire is part of Elemental Excelerator’s 2019 cohort.

Brice Nzeukou, Ampaire product manager, said the company would be bringing a retrofitted Cessna 337 Skymaster to Maui.

“It’s a really unique aircraft because it has one combustion engine in the front and an electrical motor in the back,” Nzeukou said. “We’re bringing that aircraft to Maui and working with Mokulele to figure out how to operationally include a hybrid electric aircraft into a fleet.”

Nzeukou said the advantages of an electric aircraft come down to maintenance and fuel costs. Maintenance on a traditional combustion engine can be costly. For the kind of aircraft that Mokulele flies, it costs about $300,000 to $400,000 to overhaul the engine every 5,000 to 6,000 hours of operation.

“For an electric motor, it’s much less complicated,” Nzeukou said. “It really only has one moving part, so the time between major overhauls is much longer.”

Fuel is another huge cost. Switching to electric generation is much cheaper, even in a place like Hawaii where electricity is generally more expensive than other places, Nzeukou said. He estimated that an electric aircraft could reduce fuel costs for Mokulele by 50 to 70 percent.

McKinney said that Mokulele will offer Ampaire hangar space at the Kahului Airport, as well as parts, supplies, pilots and mechanics to help further the research. He said the tests are scheduled to start in September and run over a period of six months in various weather conditions.

The Kahului-to-Hana route “made sense” because it would take the plane across Maui and would be all over land, McKinney said. It’s also representative of a route that’s hard to drive but easy to fly.

Mokulele isn’t planning to retrofit any of its planes for now; the technology would first have to be approved by the Federal Aviation Administration and be “completely ready for the market before it would go on one of our airplanes,” McKinney explained. However, he’s hopeful it can eventually be “a game changer for the industry.”

“I think it’s going to have to start in the short-haul market, kind of like what Mokulele does, until the technology advances,” McKinney said. “I don’t see it replacing large jets any time soon, but it could really make a huge difference for the carriers like us that do 100- to 200-mile legs.”

The technology could also allow carriers to offer short trips between cities that currently aren’t as cost-effective with combustion engine aircraft. For example, McKinney said, there are “lots of tiny, short-hop” routes in the Los Angeles area, where Mokulele provides Essential Air Service.

Clean aviation technology is a fast-growing frontier, spurred on by everyone from startups to industry giants. In 2016, the experimental single-seated Solar Impulse 2 became the first solar-powered aircraft to complete an around-the-world journey. In 2017, Airbus, Rolls-Royce and Siemens announced that they planned to develop the E-Fan X, a hybrid electric aircraft, with test flights scheduled to start by the end of 2020 and public flights projected the following year. And, last year, aviation startup Zunum Aero set a goal of delivering hybrid electric planes to the market in 2022.

Nzeukou said that electric-powered aircraft could catch on faster than electric vehicles, because the cost of parts for an electric aircraft are comparable to the costs for a combustion engine. Components for electric vehicles, meanwhile, are more expensive than for gasoline-powered cars. In the long run, airports will have to start thinking about putting in the “robust charging infrastructure” needed for the new aircraft.

Nzeukou said Ampaire is “laser-focused” on bringing retrofitted planes to the market, but that doesn’t mean the company won’t look into building all-electric aircraft from the ground up in the future.

For now, “we see retrofitting as the most practical and most compelling proposition for aviation,” he said.

Nzeukou was excited for Ampaire to debut its technology in Hawaii, which has been on “the forefront of green technology” in many ways.

“This is kind of the perfect proving ground for us, especially given the challenges of geography,” Nzeukou said. “It kind of showcases really why electric aviation in the future is going to be really important. It will help make flights more accessible to more people.”

* Colleen Uechi can be reached at cuechi@mauinews.com.


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