But the ride-hailing company is nonetheless forging ahead with plans to make a Blade Runner vision of transportation - flying cars - a reality by 2020.
Uber chief product officer Jeff Holden planned to announce at the Web Summit conference in Lisbon Wednesday that Los Angeles will join Dallas as the first two cities to host the company's proposed network of flying vehicles. He said the company expects L.A. residents to be making "heavy use" of the service by the time it hosts the 2028 Olympics.
Holden also said Uber signed an agreement with NASA to help develop a specialised air traffic control network to keep track of our newly crowded skies.
"Technology will allow L.A. residents to literally fly over the city's historically bad traffic, giving them time back to use in far more productive ways," Holden said in comments shared with USA TODAY. "At scale, we expect UberAir will perform tens of thousands of flights each day across the city."
In a special-effects laden video screened for conference attendees, called "Closer Than You Think," a woman is seen heading to an Uber Skyport on the roof of a tall building.
She checks in with her app for an UberAir flight, and joins three other passengers in a piloted electric plane that looks like a small Cessna with the exception of rotating wing-mounted propellors that swivel, enabling the craft to take off vertically like a helicopter.
To keep tabs on its sky-bound traffic, Uber said it will work with NASA on a range of Unmanned Traffic Management and Unmanned Aerial Systems projects that in theory will prevent catastrophic mid-air accidents from happening in the skies above dense urban zones.
"UberAir will be performing far more flights over cities on a daily basis than has ever been done before," said Holden. "Doing this safely and efficiently is going to require a foundational change in airspace management technologies."
Uber also announced that it signed an agreement with Los Angeles' Sandstone Properties to develop its Skyport roof-top take-off and landing terminals. Sandstone has 20 buildings around the core of L.A. that UberAir flights could use to skip around the city.
While technological, regulatory and psychological hurdles remain, the prospect of flying over (or under) immovable traffic is hard to resist. Los Angeles-based Tesla CEO Elon Musk has even started a new venture, The Boring Company, which plans to drill tunnels beneath cities.
Uber's presentation featured a compelling graphic that showed how a ride in an Uber car from Los Angeles International Airport to the downtown Staples Center would typically take around an hour and 20 minutes, even though it's only a 16-mile trek.
At scale, we expect UberAir will perform tens of thousands of flights each day across the city.Uber chief product officer Jeff Holden
But take an UberAir and you'll cover the 10 miles in 27 minutes.
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