The large, 13-m (42.6-ft) top rotor is pitch-controllable, but it’s not paired with a tail rotor, and it doesn’t appear to be collective-controllable. In these ways, it’s like a gyroplane – but gyroplanes by definition use unpowered top rotors. The Linx P9 uses an electric motor to spin the top rotor up fast enough for vertical takeoff and landing, where gyroplanes typically need some air speed to get off the ground.

Once aloft, the pusher props kick in, and once airspeed comes up, the wings take over 90% of the lift duties, and the top rotor can be slowed right down. This reduces drag, and also more or less eliminates the asymmetrical lift that helicopters develop due to retreating blade stall.

Secondly, they’re certifiable under existing regulations, and while they’re uncommon, they’re at least relatively well-understood by aviation authorities where eVTOL certification is an entirely new process that regulators are struggling to define as they go. So there’s potentially an easier path to commercial type certification here, and that reduces risk.