While Uber Technologies Inc. sees the launch of its self-driving car program as a step forward in transportation, its drivers are not so sure.

Uber announced Wednesday that it had begun a pilot program of self-driving cars in Pittsburgh for select passengers. Right now, the driverless cars come with a human engineer who intervenes when necessary, but drivers fear a future in which they will be entirely replaced by software and sensors.

Jim Conigliaro Jr., founder of the Independent Drivers Guild, which represents 35,000 Uber drivers in the New York City area, said he found the launch “concerning” particularly because Uber has been working with regulators to allow ride-hailing in cities on the premise that it brings jobs to the community.

“We don’t expect Uber to move to driverless cars in New York City anytime soon, but they can expect we would launch an aggressive campaign, the likes of which they have yet to see, to halt such a move,” Conigliaro Jr. said in an email.

Conigliaro added that New York City currently bans driverless cars and his group would “aggressively fight” to keep those laws in place. New York law stipulates that drivers must have one hand on the steering wheel at all time, a stronger standard than other states.

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An Uber spokesperson said the company knows drivers are concerned and noted that it expects drivers to be part of the equation, even after Uber works out self-driving issues like dealing with bad weather.

“Even when these technology issues are fixed, we believe ride-sharing will be a mix—with rides provided by drivers and Self-Driving Ubers,” a spokesperson said.

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That expected mix is partly because of the limitations of software and the need to have drivers deal with unique passenger issues, according to Uber. The company added that it expects the program to create additional jobs in maintenance, as the cars are expected to be on the road 24 hours a day.

Still, Harry Campbell, who blogs about the industry at The RideShare Guy and still drives a few hours a week for Uber and Lyft, said that safety monitors in the car are reassuring because Uber hasn’t reached what Campbell sees as the true cost-cutting step of removing drivers entirely from the equation. One big cost for Uber has been the subsidies it offers to drivers. It does not pay drivers set salaries nor benefits, instead taking a percentage commission from the drivers’ fares.

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When the car is solely self-driving, without requiring human intervention, Campbell said he would be more concerned. But he sees that as more of a slow transition.

“It feels weird because you know that at some point in the future you won’t have a job, you just don’t know when,” Campbell said.

While Campbell sees a silver lining of sorts with Uber’s planned mixture of self-driving cars and drivers, he said he is not convinced by the argument that the autonomous vehicles will create potential maintenance jobs for the displaced drivers.

“I don’t think many Uber drivers, as they are kicked out of driving for Uber, will want to go maintain those cars,” he said.

Others are willing to give up their job for the greater good. Paul Conley, who drives in Maine a few hours a week, believes his days of supplementing income this way are numbered, but sees it as great improvement in safety.

“If I get replaced by a computer, then that’s not a huge loss for me,” Conley said.