Originally Posted by
MechEngr
The design likely keeps the fixed vertical rotors to use for pitch and roll control in forward flight,
It depends on the design as there are a number of variations. With the Joby all props transition forward in horizontal flight. On the Archer the forward props transition horizontal but the aft props are fixed vertical. The Volocopter keeps all props vertical. And then there is the Jaunt that has a single main rotor with fixed horizontal props which will actually pursue Part 27/29 certification vs the new up and coming eVTOL rules.