[1] The Firefly is a modified Sikorsky S-300C helicopter with its engine replaced by an electric motor and two lithium-ion battery packs.

[4] Sikorsky Innovations director Chris Van Buiten stated that the development of the Firefly was intended to demonstrate the technology required for vertical electric flight.

[4] The battery packs, manufactured by Gaia Power Technologies, have a total of 300 cells and produce about 370 volts.

[1] The electric motor is expected to fly with much less noise, emissions and vibration and require shorter maintenance periods over the life of the aircraft.

[1] Eagle Aviation Technologies, LLC, installed the new permanent-magnet electric motor and digital controller from U.S.