Sikorsky Firefly
| {{Infobox aircraft begin
| name = Firefly | image = Sikorsky Firefly.jpg | caption = Sikorsky Firefly }}{{Infobox aircraft type | type = Light Experimental electric helicopter | manufacturer = Sikorsky Aircraft | first flight = | introduced = | retired = | status = Defunct | primary user = | more users = | produced = | number built = | unit cost = | developed from = Sikorsky S-300 | variants with their own articles = | developed into = }} |
The Sikorsky Firefly is an all-electric helicopter built for research purposes by Sikorsky Aircraft. It has been called the world's "first all-electric helicopter".Burgeson, John, [https://www.ctpost.com/news/article/Sikorsky-rolls-out-first-all-electric-helicopter-590195.php "Sikorsky to debut first all-electric helicopter"] {{Webarchive|url=https://web.archive.org/web/20201020041759/https://www.ctpost.com/news/article/Sikorsky-rolls-out-first-all-electric-helicopter-590195.php|date=2020-10-20}}, Connecticut Post of Bridgeport, Connecticut, July 25, 2010 The Firefly is a modified Sikorsky S-300C helicopter with its engine replaced by an electric motor and two lithium-ion battery packs. The helicopter would hold only the pilot and no passengers. Sikorsky reported an operating time of 12 to 15 minutes and a top speed of {{convert|80|kn|km/h mph|abbr=on}}.{{Cite web |title=Sikorsky Firefly (technology demonstrator) (defunct) |url=https://evtol.news/sikorsky-firefly/ |access-date=2024-11-27 |website=evtol.news |language=en}}
It was expected that the helicopter would make its first flight in late 2010 or early 2011. For undisclosed reasons, the helicopter was never flown and the project is now defunct.
History
Sikorsky announced the aircraft at the Farnborough International Air Show in the United Kingdom on July 19, 2010, and displayed it for the first time at the Experimental Aircraft Association's AirVenture 2010 convention in Oshkosh, Wisconsin, on July 26. Upon the Firefly's announcement, Sikorsky revealed that they had been working on the project for over two years. The cost of the project was never disclosed.
Development
The Firefly was created by replacing the engine of the S-300C light helicopter, which began production in 1964 as the Hughes 300.{{Cite web |title=Hughes Model 269/300 helicopter - development history, photos, technical data |url=http://www.aviastar.org/helicopters_eng/mcdonnel-200.php |access-date=2024-11-27 |website=www.aviastar.org}} The S-300C's Lycoming {{convert|190|hp|kW|abbr=on}}, 5.9-liter, 4-cylinder gasoline engine was replaced with an electric motor, a new motor mount, and two battery packs located on each side of the pilot. The rotor control, transmission and other systems were left essentially unchanged. The project was inspired by observing electric drag cars.Dickinson, Boonsri, [https://www.greentechmedia.com/articles/read/an-all-electric-helicopter-will-it-fly "An All-Electric Helicopter: How Far Will It Fly? Is Project Firefly at Silkorsky Innovations the start of silent flight?"], Greentech Media, August 20, 2010, retrieved May 1, 2018
Sikorsky Innovations director Chris Van Buiten stated that the development of the Firefly was intended to demonstrate the technology required for vertical electric flight.{{Cite web |last=Patrascu |first=Daniel |date=2011-01-13 |title=Sikorsky Firefly Electric Helo Nearing Test Flight |url=https://www.autoevolution.com/news/sikorsky-firefly-electric-helo-nearing-test-flight-29596.html |access-date=2024-11-28 |website=autoevolution |language=en}}
Electric motor and battery
The high-efficiency electric motor is powered by two 45Ah lithium-ion battery packs, each of which weighs {{convert|585|lb|kg}}. The battery packs, manufactured by Gaia Power Technologies, have a total of 300 cells and produce about 370 volts. 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. The electric motor and controller system weighs {{convert|180|lb|kg|abbr=on}}.Smith, Dale, [http://www.rotorandwing.com/2011/01/12/all-electric-sikorsky-firefly-setting-the-curve/ "All-Electric Sikorsky Firefly: Setting the Curve"] {{Webarchive|url=https://web.archive.org/web/20201103090901/https://www.rotorandwing.com/2011/01/12/all-electric-sikorsky-firefly-setting-the-curve/ |date=2020-11-03 }}, January 12, 2011, Rotor and Wing International, retrieved May 1, 2018 Empty weight is close to the {{convert|2,050|lb|kg|adj=on}} MTOW.Dubois, Thierry [https://www.ainonline.com/aviation-news/2011-03-06/electric-firefly-will-feel-conventional-s-300c-says-sikorsky "Electric Firefly will feel like a conventional S-300C, says Sikorsky"], March 6, 2011, AIN Online, retrieved May 1, 2018 The batteries, motor and electronic components are air cooled, and the batteries have 15 minute endurance.
If the aircraft completely loses power, it can auto-rotate for a safe landing. The pilot would have plenty of warning if the batteries ran down during flight.
Eagle Aviation Technologies, LLC, installed the new permanent-magnet electric motor and digital controller from U.S. Hybrid, and the batteries.News release, [https://web.archive.org/web/20131203011019/http://www.sikorsky.com/About+Sikorsky/News/Press+Details?pressvcmid=989b1cb3a2be9210VgnVCM1000004f62529fRCRD "Sikorsky Introduces "Project Firefly" Electric Helicopter Demonstrator"], July 19, 2010, Sikorsky Aircraft, Internet Archive December 3, 2013, retrieved May 1, 2018
See also
{{Portal|Aviation}}
References
{{Reflist}}
External links
{{commons category|Sikorsky Firefly}}
- [https://web.archive.org/web/20160304053057/http://www.sikorsky.com/Pages/Innovation/Technologies/FireflyTechnology.aspx Firefly™ Technology Demonstrator] Firefly Sikorsky corporate page (Internet Archive)
- [https://www.youtube.com/watch?v=oD8TfjDMYT0 Sikorsky Firefly: An Electric Helicopter] AvWeb report from Oshkosh EAA AirVenture 2010. Interview with Sikorsky Innovations project manager Jonathan Hartman.
{{Sikorsky Aircraft}}
Category:2010s United States helicopters
Category:2010s United States experimental aircraft
Category:Single-rotor helicopters