In the United States (US), Los Angeles-based electric aircraft developer Ampaire Inc., has announced that is the first company to complete a demonstration flight of a hybrid-electric aircraft along an actual airline route. The company flew its Electric EEL aircraft on November 22, 2020, on a 20-minute flight in Hawaii (HI), from Maui’s Kahului Airport across the island to Hana and back on a single charge.
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According to a statement, Ampaire is now flying the route regularly in a one-month demonstration program with Hawai‘i-based Mokulele Airlines Inc., one of 15 airlines to have signed a Letter of Interest with the company.
We’re following the successful path of hybrid-electric automobiles in transforming ground transportation by taking that model to the sky. By upgrading current aircraft with hybrid-electric propulsion we can enter the market quickly and take advantage of existing infrastructure for fixed-wing aviation, said Kevin Noertker, CEO of Ampaire.
A wholly-owned subsidiary of Southern Airways Corporation, one of the largest commuter airlines in the United States, Mokulele Airlines currently serves 37 cities with more than 220 peak-day departures from hubs at Baltimore, Dallas/Ft. Worth, Honolulu, Kahului, Los Angeles, Memphis, Nantucket, Palm Beach, and Pittsburgh.
Ampaire flew the largest hybrid-electric aircraft at the time in May 2019 and is exploring larger aircraft conversions with support from NASA and the US Department of Energy’s ARPA-E research arm.
Demonstrate potential and robustness
The flight trials with Mokulele Airlines are supported by Elemental Excelerator, a global climate-tech accelerator of which Ampaire is a portfolio company.
We’re excited to partner with Ampaire to pave a path to electric aviation that unlocks more accessibility to rural and island communities and increases green jobs while invigorating the aviation industry. Building a climate-positive aviation industry is about much more than just a plane. It requires rethinking everything from airport infrastructure to pilot behavior, and that’s what this project is really proving, said Danielle J. Harris, Director of Mobility Innovation at Elemental Excelerator.
It is the first use of a hybrid-electric aircraft under the Federal Aviation Administration’s (FAA’s) Experimental-Market Survey category, allowing Ampaire to fly with their crew and essential personnel for crew training and other exploratory market activity.
According to Noertker, the trials serve two purposes: demonstrating electric aviation’s potential to reduce harmful emissions and evaluating the robustness of Ampaire technology.
We can take lessons from this series of flights and apply them to subsequent, larger aircraft designs already in the works, Kevin Noertker said.
The Electric EEL technology demonstrator used in the Mokulele trials is an upgrade of the popular six-seat Cessna 337 twin-engine piston aircraft. The aircraft has a 300-horsepower piston engine in the rear and a 160 kW-capable electric power unit in front, plus a battery pack carried in an under-fuselage aero-optimized shell.
Due to the contribution of the electric power unit, fuel consumption, and carbon dioxide (CO2) emissions are reduced by approximately 40-50 percent.
The future for regional airlines is electric. We expect to put hybrid- and all-electric designs into service as soon as possible, and we know other regionals are watching us with great interest, said Stan Little, CEO of Southern Airways.
Ground equipment a 3-phase power outlet
For the flight trials, the only change to ground equipment was the requirement to wire a Mokulele hangar with a 208-volt 3-phase outlet. Ampaire has been working with the Hawai‘i Department of Transportation and the Hawaiian Electric Company to explore longer-term infrastructure solutions to support a fleet of hybrid- or fully-electric aircraft.
The market for electric aircraft will expand as airlines perceive that electric aviation is not only environmentally desirable but economically advantageous. Electricity cost is an order of magnitude less expensive in comparison to fuel, which is the largest cost item for airlines, said Kevin Noertker.
According to Noertker, UBS, the Swiss investment bank, forecasts a US$178 billion market for hybrid-electric aircraft.
