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Comment by owenmarshall | Hacker News Reader

From the article, emphasis theirs:

Vehicle tests confirmed that one particular dead task would result in loss of throttle control, and that the driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration.

Every one of those approaches you suggested are, in many modern cars, fully software driven. And the article even shows an example of how a bug in the software can only be resolved through the exact opposite of what a rational person would do in a crisis.

I think the only actual mechanical failsafe left is the handbrake. Please tell me that's still sacred...

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Handbrakes are almost always mechanical cables, but they're almost definitely not enough to stop a car under high engine output. They're mechanical and not power-boosted (see comments on how much force is needed on the brake pedal without power assistance) and plus, most people have at some point driven around for a few miles before they realized that beeping sound was the parking brake stuck on the whole time.

Oh, of course - I've left the "emergency 'smell funny' lever" on before (thanks Mitch Hedberg).

So you're probably right, it's a stretch to call the handbrake something useful in emergencies when in reality it probably wouldn't perform that function.

It's called a parking break now. Only useful when the car isn't moving :)

Even if you are able to, fully engaging the handbrake in a car at highway speeds, while the drivetrain is in runaway, wouldn't be helpful.

source: I have tested this at ~30-40 mph and nothing about that experience leads me to believe that it would be safer if I had been going faster, and at full throttle.

It might be sensible, though, to couple a killswitch to the handbrake, so that engaging it switches the engine off, or cuts off all electronic control, or something.

I don't drive cars, so i have no idea if that would conflict with normal uses of the handbrake. Perhaps it could have a position beyond the normal brake-engaging position that did this? So that if someone panics and yanks on it as hard as they can, they get the result they probably want.

Handbrakes usually brake only the rear wheels. If you turn the handbrake fully on while driving at higher speeds, you may lose directional-control.

Very well said. The focus on convenience and cool features over safety makes me really sad, and want to force automotive engineers to watch some Alan Kay talks. He loves to talk how people who don't know the history and basics of their craft will arrive at inferior solutions, for example in this one: http://www.youtube.com/watch?v=FvmTSpJU-Xc

Electric hand brake is very common in modern cars. Luckily most the features you listed are usually implemented in separate ECUs. Neutral probably goes through the gearbox ecu, handbrake through the brake ecu etc.

>Electric hand brake is very common in modern cars.

Yuck!

>Luckily most the features you listed are usually implemented in separate ECUs.

What concerns me would be how the systems handle unexpected inputs.

In the article it notes that the only way to end one unexpected acceleration event was to stop using the brakes. I'm not sure if the vehicle in question has separate controllers, but if it doesn't that's a real concern that unexpected input from one tickles a bug in another.

The parking brake is electronically controlled in a lot of new cars now.

Ah, didn't know that. Figures!

The previous sentence in the article seems to indicate that a "dead task" in this context will only happen if a specific bit in the controller's RAM is corrupted.

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