Uber customers in Pittsburgh will be able to hail a self-driving car from their phones for the first time, marking an important milestone in the race to a driverless future.

The self-driving cars will have a “supervising engineer” sitting behind the wheel (a legal requirement) to take control when necessary, and an observer in the passenger seat taking notes, Bloomberg reported. Rides in these cars will be free for the time being.

The pilot is part of Uber’s wider vision to eventually replace its 1 million plus human drivers with fully autonomous vehicles.

The Pittsburgh fleet consists of modified Volvo XC90 sport-utility vehicles. Bloomberg reports that Volvo has so far delivered a handful of them, with 100 due by the end of the year.

Uber has agreed a $300 million deal with Volvo to develop a fully autonomous car by 2021, although it also plans to partner with other car-makers.

It has also acquired Otto, a maker of self-driving technology for trucks.

Google, Apple, Tesla, Lyft and other companies have been working on self-driving technology for some time, and Ford recently announced plans to build autonomous vehicles designed for ride-sharing by 2021, but Uber is set to become the first to offer the service to customers.

Image: Boston Consulting Group

Uber CEO Travis Kalanick believes that when self-driving cars begin to go mainstream, personal car ownership will quickly become a thing of the past.

Speaking in June at the World Economic Forum’s Annual Meeting of the New Champions in Tianjin, China, he said: “You might own a car like maybe some people own a horse. You know, they might take a ride on the weekends or something.”

Kalanick and other proponents of self-driving cars argue that they will make the roads safer. Research backs this up – a McKinsey&Company report estimates that autonomous cars could reduce traffic fatalities by up to 90% by mid-century.

However, there have been several high-profile accidents recently, including a fatal crash in May involving a Tesla Model S that was in autopilot mode.

“Google has been working on self-driving cars for eight years. And there’s a reason. A million people die every year in cars, from human error. People making mistakes when they’re driving. And there are tens of millions of people getting injured,” Kalanick said.

“Then think of the trillions of hours that we spend behind the wheel driving,” he added. “There will be a huge, huge positive impact for society when driverless cars become a thing.”

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