Kempner: Self-driving Tesla takes me for 70-mph spin on Ga. 400

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We are destined for a future in which most of our cars drive themselves.

But since we aren't there yet, I tried something closer to what I'd call half-driving. I turned my life over to the autopilot setting on a $100,000 Tesla Model S, which let the electric car drive itself, sort of, kind of.

It doesn’t respond to stop signs or red lights. It doesn’t drive a route to downtown, turning down one street and then onto another on its own. What it does do, at least on a highway, still seems incredible.

Picture going 70 miles per hour on Ga. 400 when the highway curves, the cars ahead speeding up and slowing down, vehicles on either side of you and – this is the crucial part — you are admonished to avoid braking, accelerating or steering the Tesla, because the car does all of that for you.

“You don’t want to override anything,” the Tesla PR person told me.

What worried me was that she also cautioned me to keep my hands on the wheel, if only lightly, and to remain vigilant. I inferred this was because, well, it would be crazy to trust a car to drive itself.

“We still recommend you be in full control of the car,” she said. My attention was merely “an added safety feature.”

How do I know when I should and shouldn’t take control? I asked.

“I don’t have that answer,” she replied.

Very comforting.

The first 20 minutes of driving in autopilot is an exercise in trust and willpower.

My body tensed. I definitely winced. I may have grunted. Or yelped. My foot had a mind of its own and hovered just above the brake pedal. Twice my instincts kicked in and I took control. This was nothing like the semi-autonomous 20-ton bulldozer I drove and recently wrote about.

Other drivers on Ga. 400 had no idea there wasn’t a person driving the fancy car beside them.

The Tesla stays in its lane by using cameras, radar and sensors to watch lane lines or, if they are faded, the vehicle in front of it. The car slows itself or stops as needed, then speeds up again. It steers through curves.

Flip on a turn signal, and the Tesla will look for the right time to change lanes, then cross over when it sees fit.

Which is where the car and I had a disagreement.

I’m not good about delegating to a machine. The Tesla drives like it wants to drive, which odds are isn’t exactly the way you would. I became a bit of a front-seat driver. Once or twice the Tesla was a wimp, slowing down when it saw something minor ahead that I knew was nothing meaningful.

The real test was when I purposely hit the turn signal when there wasn’t much of a gap between cars in the next lane over.

The car waited a beat, then moved like it was going to get over. To me it felt like it was going to cut off another driver. My nerves turned from steel to cooked spaghetti. I tapped the brake and stopped it from switching lanes.

“That’s what you don’t want to do,” Tesla’s backseat PR person told me. The Tesla would have sped up and gotten over safely, she said.

Semi-autonomous or partially self-driving vehicles have suddenly gotten very real. Several automakers are marketing vehicles that offer options like blind-spot monitoring, cruise control that changes speed automatically, self-parallel parking, accident-avoidance braking and lane control. For now, these mass-market cars still don’t respond to lots of other issues that a fully-automated car would have to deal with.

But that day sure feels like its on the way. Google’s driverless test vehicles handle all sorts of real-life issues and, according to a company video, can even read and react to the hand signals of bicyclists preparing to turn.

I’ve wondered what we’ll be doing with our hands when we no longer use them to drive.

Arm curls in our car gyms? Writing tomorrow’s column on a car desk? Blending breakfast in a car Cuisinart? Picking out a Netflix movie? Flipping through newspapers online or in print (please, please, please, please).

I bet a lot of us will end up working more. Commutes in metro Atlanta average around 30 minutes one way. So that's an extra hour a day to use for good or ill.

For now, though, we are in a twilight zone. Cars that are just semi-autonomous require a new, murky concept of driving while not driving. Trust the machine. But not really. It’s not complete freedom or an option to doze (at least no safely); It’s just a more Zen kind of motoring once you get comfortable with it.

Chandler McCormack, of Atlanta, initially thought the autopilot function on his Tesla was creepy. But now, he told me, it seems safer and easier than if he was driving the old-fashioned way.

“It’s a much more laid back experience,” said McCormack, who is CEO of OxBlue, a small tech company.

Of course, he has to force himself to not look at his iPad for minutes at a time or otherwise completely disengage from his driving duties.

“It’s giving you back time you can’t do much with,” he said. “It’s giving you quiet time.”

He notices more about what he’s passing along the highway. And he talks more with his wife and kids when they are in the car.

Maybe that’s one good thing about half-driving. It’s the peaceful lull we get before fully self-driving cars force us to do productive, responsible or ridiculously foolish things with the new free time we’ll have.