Overair Assembles First Full-Scale eVTOL Prototype

Overair has completed assembly of the first full-scale prototype of its Butterfly eVTOL aircraft with the company set to begin flight testing in early 2024 By Joe Macey / 20 Dec 2023
Overair Completes Assembly of First Full-Scale Butterfly eVTOL Prototype
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Overair has completed assembly of the first full-scale prototype of its Butterfly eVTOL aircraft. 

This marks a pivotal milestone for the original equipment manufacturer (OEM) following the validation of their full-scale propulsion technology via a 2022 truck-based test. 

This achievement signals the start of Overair’s vehicle-level testing phase at its Santa Ana, California headquarters, before moving the aircraft to its expansive flight test facility in Victorville, California.

Initial tests, scheduled to begin in early 2024, will focus on validating Butterfly’s propulsion systems, flight control mechanics, safety features, and operational efficiency. The testing will also assess the aircraft’s 55-decibel noise target and performance envelope across diverse flight and weather conditions.

“Assembling our first full-scale prototype vehicle marks the culmination of years of industry expertise, meticulous development planning, innovative engineering, and the hard work of the entire Overair team,” said Ben Tigner, CEO of Overair. “This seamless transition from propulsion testing to a full-scale prototype underscores our dedication to redefining the eVTOL landscape with safer, quieter, and more reliable aircraft.”

Born out of Karem Aircraft, Overair is leveraging VTOL expertise to efficiently develop, manufacture, test and refine its vehicle as it pursues certification and operation designed to match the Federal Aviation Administration’s Advanced Air Mobility Implementation Plan. According to Overair, this vehicle will be the first-ever eVTOL aircraft to be built around Optimum Speed Tilt Rotor (OSTR) and Individual Blade Control (IBC) technologies.

OSTR technology varies propeller revolutions per minute (RPM) to increase efficiency across vertical, transition, and forward flight phases and can reduce power demand at hover by 60%. IBC reduces vibration and propeller loads, enhances safety, provides smoother ride quality, and lowers maintenance costs. Together, these technologies deliver an efficient, quiet, and reliable propulsion system in almost any weather, temperature, or altitude. Additionally, with fewer moving parts than traditional tiltrotors and no single points of failure, Overair owns a unique position in the market.

“I’m thrilled to see this vehicle come to life,” said Abe Karem, Founder of Karem Aircraft. “Using these advanced technologies, Butterfly is bringing a completely novel approach to aviation and is poised to redefine air transportation.”

Butterfly’s signature design, largely attributable to its advanced propulsion technologies, is said to be unique in the eVTOL market. Featuring four oversized rotors, a spacious cabin, high payload, and the quietest, most efficient operation in its class, Overair’s Butterfly will be perfectly suited for passenger, medical, cargo, and military applications.

“Since day one, Overair has been committed to developing an aircraft that extends efficient air transportation to a broader audience; an aircraft that will be welcomed by local communities, passengers, and operators alike,” added Valerie Manning, Chief Commercial Officer at Overair. “Our prototype is where we begin real-world, full-scale validation of these fundamental design principles.”

As Overair reaches critical aircraft development milestones with the completion and subsequent testing of its full-scale prototype, it is also focused on preparing for future operations. According to Overair, the company has attracted significant market interest from customers both in commercial as well as military and across several geographies, leading to a deep understanding of the product-market fit, including the recent announcement of an SBIR award by the US Navy to further advance the IBC system.

A foundation built on product, infrastructure, and market expertise is said to be key to accelerating successful AAM adoption. Overair believes that with partners such as Dallas Fort-Worth Airport, the City of Arlington, Texas, and Jeju Island, South Korea, it will play a key role in advancing the development of global advanced air mobility infrastructure and leading the deployment of eVTOL operations at scale.

Posted by Joe Macey Joseph Macey is a Content Specialist at Advanced Air Mobility International, focusing on emerging aviation technologies since joining in 2022. He has particular expertise in eVTOLs, vertiports, and propulsion systems. A graduate of Falmouth University in Journalism, Joseph began his career in 2019 as a local reporter. His journalism experience sharpens both his reporting and interview skills, enabling him to deliver well-informed, authoritative insights on the latest trends in the aviation sector. Connect

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