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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 OEM following the validation of its 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.
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," says CEO Ben Tigner. "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 decades of VTOL expertise to efficiently develop, manufacture, test and refine its vehicle as it pursues certification and operation designed to match the FAA's AAM Implementation Plan. 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 to increase efficiency across vertical, transition and forward flight phases, and can reduce power demand at hover by 60 per cent. 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 there are fewer moving parts than traditional tiltrotors and no single points of failure.
"I'm thrilled to see this vehicle come to life," says Abe Karem, founder of Karem Aircraft and father of UAV drone technology. "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, features four oversized rotors, a spacious cabin, high payload and the quietest, most efficient operation in its class. It will suit 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," says CCO Valerie Manning. "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. The company has attracted significant market interest from customers both in the commercial and military arenas, as well as across several geographies, leading to a deep understanding of the product-market fit and a SBIR award by the US Navy to further advance the IBC system.
A foundation built on product, infrastructure and market expertise is 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 AAM infrastructure and leading the deployment of eVTOL operations at scale.