The two companies will undertake flight testing in preparation for the K-UAM Grand Challenge, South Korea's demo programme that will test UAM in an urban environment and support its commercialisation by 2025.

The Dayton, Ohio region's eVTOL tagline has urged companies to leverage its network of resources and 'come here to test, stay here to build.' Joby is doing exactly that.

H2Fly completed a series of piloted flights with its HY4 demonstrator aircraft, including one that lasted more than three hours, fitted with a fuel cell propulsion system and liquid hydrogen for the entire flight.