Ampaire flies its second technology demonstrator

Ampaire, a pioneer in electric aviation, flew its second technology demonstrator on Thursday September 10th The aircraft is a refined version of its Cessna 337 “Electric EEL” hybrid electric aircraft conversion.

The company refers to the new flight test aircraft as the Hawaii Bird, as it will be flown by Ampaire and Mokulele Airlines pilots on air routes in Hawaii later this year in a series of demonstration flights. When the aircraft flies on Maui, it will be the first time an electrically powered aircraft has flown under an FAA “market survey” experimental aircraft certificate in order to gain real world flight experience.

“Since flying our first Electric EEL last year, we have made substantial improvements to the power train for efficiency, increased performance, reliability and safety,” said Ampaire CEO Kevin Noertker. “This technology is scalable with wide applications for scheduled passenger and cargo services, as well as charter services. Our flights with Mokulele will be an opportunity to test both the aircraft and the infrastructure required to advance electric aviation and transport access in Hawaii.”

Noertker said he expected the company to leverage knowledge from the 337 conversion program into retrof its of larger regional aircraft that could enter service in just a few years.

The Hawaii Bird is powered by a conventional combustion engine a 310 horsepower/231 kW Continental IO 550) in the tail, and a 200kW capable electric motor in the nose, limited in this application to 120 kW. In this second conversion, the aircraft’s battery pack has been relocated from inside the cabin to the underside of the fuselage and enclosed in a composite aero optimized shell. The new configuration frees cabin space for flight test engineers, test equipment, and observers. An aircraft such as Ampaire’s Electric EEL can cut direct operating costs and emissions by 40-50% versus conventional aircraft, playing an essential part in helping Hawaii reach its goal of 100% renewable energy for electricity by 2045.

In this latest conversion, the Electric Power Unit (used by the aircraft is designed for improved energy efficiency with less weight. The EPU has better thermal margins thanks to a liquid cooling system versus the previous air cooling system. The aircraft also has improved cockpit instrumentation and power controls for monitoring outputs from the combustion engine and electric motor. Designed to cruise at 120 knots for 1 hour and 15 minutes, plus a 30 minute reserve, The Hawaii Bird can fly most Mokulele routes round trip before a required recharge.

During its 35 minute first flight, test pilot Justin Gillen climbed to 3,000 feet and made a series of handling and power checks, assessing engine and motor performance, temperatures and other readings, with both powerplants performing as expected. The aircraft will fly for a series of checkouts before being shipped to Hawaii in October.

Ampaire is working in partnership with Elemental Excelerator, one of the world’s leading climate tech accelerators with more than 99 startups within its portfolio, to fund the Mokulele flight trials. With headquarters in Hawaii, Elemental understands the unique challenges and opportunities around transportation, and the team is leveraging its deep relationships across public, private, and nonprofit sectors to help startups such as Ampaire deploy at the community level.

“Ampaire’s hybrid electrically powered aircraft becoming an integral part of Hawaii’s transportation ecosystem will pave the way towards affordable and sustainable air transit throughout the U.S.,” said Danielle J. Harris, Director of Mobility Innovation of Elemental Excelerator. “The success of this second flight test aircraft is a strong signal that innovative solutions like Ampaire’s electric powered aircraft play a key role in helping a heavily visited state like Hawaii reach its ambitious renewable energy goals and meet its unique transit needs.”

Stan Little, Chairman and CEO of Southern Airways, which owns Mokulele, said, “Electric aviation is the future for the commuter airline industry, and through our partnership with Ampaire, we intend to be at the forefront of that innovation. These test flights hold the promise of expanding inter island service by lowering costs while reducing our environmental footprint both great benefits to the people of Hawaii What we are doing today is what everyone will be doing someday.”

About Ampaire
Ampaire is leading the charge in aircraft electrification. The Los Angeles based company’s mission is to be the world’s most trusted developer of practical and compelling electric aircraft. To start, the company is retrofitting existing passenger aircraft to electric power the quickest and most capital efficient approach to making commercial electric air travel a reality. 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 ARPAE research arm. Ampaire’s vision is to make flights more accessible to more people from more airports by providing electric aircraft that are clean, quiet, and affordable Ampaire is a portfolio company of Elemental Excelerator and Los Angeles Cleantech Incubator, and Techstars, with additional support from Starburst Accelerator and others.

About Elemental Excelerator
Elemental Excelerator advances solutions to climate change and deploys them in the communities that need them the most. Each year, it finds 15-20 companies that best fit its mission and funds each company up to $1 million to improve systems that impact people’s lives:energy, mobility, water, agriculture, and beyond. To date, it has awarded over $36 million to 99 companies. For more information, please visit

About Southern Airways and Mokulele Airlines
Founded in 2013, Southern Airways has qu ickly grown to become one of the largest commuter airlines in the United States. Operating a fleet of Cessna Caravans and Grand Caravans, Southern, along with its Hawaiian subsidiary, Mokulele Airlines, serves 37 cities with more than 220 peak day departur es from hubs at Baltimore, Dallas/Ft. Worth, Honolulu, Kahului, Los Angeles, Memphis, Nantucket, Palm Beach, and Pittsburgh. In Hawaii, Mokulele serves more airports with more flights than any other airline. For further information, go to, or visit us on all major social media sites.