An eVTOL that can carry five passengers plus cargo, at a 200 mph (322 kph) top speed, with a 100-mile (161 km) range, doesn’t sound like something new. But its breakthrough propulsion system, called Optimum Speed Propulsion (OSP), makes all the difference.
Unlike other VTOLs that distribute smaller propellers on the wings and tails, Butterfly uses four bigger ones that are able to spin very slowly in hover and cruise, with two major benefits. First of all, it means that hover flight requires only a small fraction of the motor power, which gives the aircraft power margins to operate even in challenging conditions, plus extra payload capacity. Secondly, it makes it the quietest eVTOL on the market.
The innovative propulsion system makes it robust enough for all-weather operation, and it’s even able to fly with one or even two propellers inoperative. Its large propellers and advanced blade dynamics are supposed to make Butterfly as efficient as airplanes in forward flight, and, at the same time, safer and quieter than helicopters, in vertical flight.
Butterfly’s developer, Abe Karem, is known as the founding father of the “age of drones”, who started creating innovative aircraft since the ‘80s. His name is associated with several military unmanned aerial vehicles, including the Predator and the A160 Hummingbird, a drone-helicopter that broke endurance and altitude records in its class.
Overair is the fourth company founded by Abe Karem, as a culmination of all his previous achievements in VTOL design. Butterfly is his most advanced aircraft yet, drawing from military expertise, for a highly-advanced civilian mobility solution.
Overair’s eVTOL is set to obtain FAA (Federal Aviation Administration) certification by 2025, and enter commercial service in 2026.