Two years after announcing plans to produce a five-seat, hydrogen-powered CityHawk eVTOL, Metro Skyways, a subsidiary of Urban Aeronautics, released more details of its design on June 2, including the hydrogen-based powertrain. While CityHawk will initially be powered by jet fuel in order to expedite its certification under the US Federal Aviation Administration (FAA) FAR Part 27, following certification it will be converted to 10,000 lb/in² (700 bar) compressed-hydrogen propulsion. Even with its new, hydrogen/Fuel Cell Stack (FCS) powertrain, Metro Skyways expects it will still meet FAA/EASA requirements for a Category A takeoff manned rotorcraft, certified for commercial operation. CityHawk capitalizes on Urban Aeronautics’ internal rotor Fancraft technology developed by the company over two decades. Apart from the addition of a second engine (or FCS in the case of the H2 variant), CityHawk is identical in configuration, size and weight class to the Multi-Role, Cormorant UAV developed by sister company Tactical Robotics Ltd. which has accumulated in excess of 300 flights.