Uber's self-driving cars are impressive - but there's still a lot they can't do

Last week, Uber rolled out its self-driving cars in a pilot program in Pittsburgh so that select users could experience the technology firsthand. But anyone who gets permission to do so will notice there's still a driver behind the wheel.

That's because Uber's self-driving cars are nowhere near fully autonomous. Uber knows that, which is why there's an engineer in the front seat overseeing the car's movements and a safety driver behind the wheel.

I got a chance to go behind the wheel, and the Uber cars are really good at maneuvering around a tricky city like Pittsburgh. The braking was smooth, the response time was quick, and it handled intersections just fine.

But there were a few times a driver had to take over. Here are the scenarios Uber's self-driving cars still have difficulty handling.