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Toray to supply advanced prepreg system for Overair’s Butterfly eVTOL

Toray Composite Materials America will be providing advanced carbon fiber and composite prepreg materials for Overair’s Butterfly eVTOL prototype program.

Butterfly Overair
Overair’s Butterfly prototype will utilize Toray’s T1100/3960 carbon fiber/epoxy resin prepreg. Toray claims its prepreg system provides high stiffness and strength for the Butterfly’s airframe and propulsion units. Overair Image

“We’re excited to be working closely with Toray’s advanced materials as we continue the development of our all-electric Butterfly experimental prototype aircraft,” said Ben Tigner, co-founder and CEO at Overair. “Our unique propulsion system requires materials that provide a unique combination of high stiffness and high strength, while also maintaining the optimal weight targets for the vehicle.”

The Butterfly prototype aircraft will utilize Toray’s T1100/3960 prepreg system, a material that the company claims is formulated for high-performance aerospace applications where the optimal ratio of strength to modulus properties is critical. This specific material is optimized for increased performance and allows for autoclave and out-of-autoclave curing

Overair recently completed full-scale testing of the Butterfly’s propulsion system, which the company said validates the eVTOL’s expected performance capabilities. Butterfly’s propeller will be showcased at the Farnborough International Airshow from July 18 to July 22 in Farnborough, England. 

“It is an honor for Toray to partner with Overair on this endeavor and provide the Butterfly a unique performance advantage with our 3960 prepreg system,” said Jeff Cross, director of business development for aerospace at Toray. “The proven performance of our materials gives me confidence that we can help achieve Overair’s objective of producing the safest, most efficient, and reliable eVTOL aircraft.” 

The eVTOL developer also has operating partnerships with offshore helicopter operator Bristow Group, which has pre-ordered up to 50 aircraft from Overair, as well as Hanwha Group, which recently injected $145 million in funding into Overair’s Butterfly program. The company said it plans to begin flight testing its experimental eVTOL prototype in the second half of 2023.

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