MW-Class Electric Propulsion: Geared or Direct Drive?

In engineering state-of-the-art MW-level powertrains for future aircraft, a recurring consideration is whether to go for direct drive or geared propulsion systems, with strong proponents on both sides of the argument. This conundrum is attested by the radically different paths pursued in various ongoing aircraft R&D programs worldwide. Taking a case study for a short-medium range aircraft and its MW-level propulsion system, this paper melds expertise in electrical machines and gearbox technologies to tackle this question fairly, considering the relevant technologies and merits/demerits.