Last year, while moving through the hordes of people at the first Farnborough Air Show in four years, it quickly became clear that a certain genre of stand had stolen the show. Huge crowds gathered to sit in model cockpits or walk around the fuselages of retired prototypes. Their promises were radical – a greener way to fly and the potential for a zero-emission aviation industry. According to the marketing material at least, this had the potential to change everything.
Electric vertical take-off and landing aircraft, or eVTOLs, represent a substantial leap forward in the aviation industry’s path to net zero. Due to limitations in battery technology, electrifying aircraft is no easy feat. The energy density of lithium-ion batteries is around 50 times less than that of jet fuel and thus makes it extremely difficult to power an electric aircraft without adding excessive weight, which would in effect ground it.
The progress made so far is impressive, with...