Elon Musk says he’s “dying to do a supersonic electric VTOL jet” — so we looked into what creating a supersonic eVTOL would actually take.

Lilium co-founder Patrick Nathen and three of his colleagues took to Reddit this week for an AMA (Ask Me Anything). We pulled out some of the highlights.

We spoke with Vertical Aerospace chief engineer Tim Williams for an update on how the company is progressing with its VA-X4 eVTOL demonstrator.

Japanese eVTOL developer SkyDrive is working with the Japan Aerospace Exploration Agency (JAXA) on aerodynamic studies for its eVTOL aircraft.

Lilium co-founder and CEO Daniel Wiegand explains the technology behind the company’s seven-seat eVTOL design in a 15-minute video.

Go behind the scenes with Beta Technologies’ Kyle Clark on the design and performance of the Alia-250 eVTOL aircraft.