Hoversurf is developing both two- and four-seat versions of its Formula hybrid-electric eVTOL aircraft. These are based on the company's patented Venturi engine technology. This consists of a total of 52 ducted fans--48 of which are used for vertical lift and the other four of which drive cruise flight. Power originates with a turbine-and-alternator combination that Hoversurf describes as a "free piston engine." Atmospheric air is pushed through the Venturi fans in a way that Hoversurf claims will increase the efficiency of the electric motors and also reduce noise. The company says that operating costs for the aircraft could be around $0.48 per mile.
As of August 2019, Hoversurf had not published a projected timeline for completing certification of the Formula aircraft. The company appears (from available video clips) to have flown a sub-scale prototype of the Formula aircraft.