The art of aircraft development has been honed over more than 100 years. Now there is a wave of Silicon Valley-inspired startups striving to streamline the process to bring advanced air mobility to market and into revenue-earning service as soon as they can.

But developing and certifying a new aircraft is a multistep process for a good reason: It works. And the startups are finding they can compress the timeline only so much. As the leaders of the electric vertical-takeoff-and-landing (eVTOL) race know, the steps cannot be skipped.

As the “horse race” progress chart shows, only one eVTOL developer, EHang, has so far made it all the way to certification and commercial operation—but only in China. The next to achieve the milestone is likely to be China’s AutoFlight, which expects to certify an uncrewed cargo version of its Prosperity eVTOL in 2024.

None of the others has yet flown a type-conforming prototype with which to begin certification testing. That step lies ahead in 2024 for Archer Aviation, Joby Aviation and Volocopter, as well as Lilium—a milestone that must be achieved early in the year if they are to achieve their commercial launch targets.

Following them is a raft of startups aiming for service entry in 2026 and beyond, with more time in hand, at least on paper—Eve Air Mobility, SkyDrive, Supernal, Vertical Aerospace and Wisk among them. For these companies, 2024 will be a year of flying full-scale demonstrators and nonconforming prototypes.

The year ahead will also be a time for fundraising. There is a price to be paid for moving fast, and the cash-burn chart shows how quickly the publicly listed eVTOL developers are consuming the funds they have raised. But there is also a prize to be won, as the orderbook chart shows. Before the many nonbinding commitments can become firm orders, the startups must meet their milestones.