The industry is moving faster than anyone has recently predicted. Take Voom, an app that matches helicopter pilots with passengers. It started servicing passengers in São Paulo in 2017, and its rapid success led to a March debut in traffic-clogged Mexico City. In the U.S., Boeing recently announced plans to test a piloted air taxi in 2019. Uber has similar plans for Dallas and Los Angeles in 2020, with an eye toward autonomous flight.

Air-taxi flights are pricey today, but costs are expected to fall. A representative from Lilium, a European operator, predicted in October that its electric five-seat air taxis will complete the Manhattan-JFK shuttle for $36 a person, significantly cheaper than cab fares, and that the price will eventually fall to $6 once flights become autonomous. The standard prediction, offered by Porsche Consulting and others, is for commercialization of air taxis to occur around 2025, but that may be overly pessimistic.

Bottlenecks for the U.S. air-taxi industry are now due to federal and state regulations, not the technology.