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Comment by henvic | Hacker News Reader

If I were automaker I'd consider allowing bursts above the maximum speed limit for a few seconds.

I'm not a fan of limiting (besides for warranty, electronics reasons) and prefer to educate rather than restrict. However, if taking this approach I believe you should consider that some people might drive in the limit and they deserve to be in power of their vehicles regardless.

Imagine if you drive near this software-limited speed and suddenly need to speed up a little bit more to avoid a dangerous situation. You simply can't. This may dangerous specially if you don't have in your mind that your speed is limited by software.

Just allow breaking out of this limit for, say, 5s so your drivers can get out of a dangerous situation instead... And if they try to abuse the system, disappoint them by blocking acceleration.

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In all of my 32 years of driving and over many many miles I've had exactly one situation where acceleration helped me avoid an accident and it wasn't anywhere near the local speed limit. On the way to visiting another HN user I was about to turn left and looking into the low sun waiting for a vehicle that was barely visible to pass. Then I moved across the lane and another vehicle appeared quite close behind the previous one. Because of staring into the sun for too long waiting for the first one I had developed a really nice blind spot for the second car to hide in. It wasn't visible to me until it was almost on top of me. That's the only time that a large engine ever made a difference (and I'd never really floored it all the way in city traffic before but that was impressive). All the other times it was the brakes that saved the day.

Meanwhile, I find that acceleration has helped me to avoid accidents numerous times in my ~17 years driving. Everybody has different experiences.

I have absolutely been in a situation where acceleration was the deciding factor (apart from quick reflexes) in avoiding a crash.

However, it certainly was not at highway speeds. There's simply no reason to need to go faster than 180kmh on public roads.

Regarding sudden acceleration (and it's a good time to remember acceleration isn't speed) avoiding accidents...

I live in Brazil. There is a tax supposed to cause road accidents here. If your powertrain is > 1.0, the tax you pay when buying cars has a sudden increase. Therefore, many if not most people buy 1.0 cars here (). This is valid even for some that are not consider lower end here (though would be anywhere else in the civilized world).

It's actually the most common type of crash on highways here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907522/

Anyways, one great reason of accidents here is frontal collisions. People either don't take into account that they are driving snails, not cars, and try to take over on the road but fail to do so at an adequate distance.

The thing is if you are at, say, 80km/h it gets really hard to increase your speed 5 or 10km/h in short amount of time. I believe that people driving powerful cars don't think about this often, and all it takes is an idiot to tailgate you while you are trying to take over to make shit happens. Another unfortunate thing is that you might find yourself tailgating the vehicle upfront before taking over it to reduce the needed distance.

* highways here are usually one lane each way most times. Sometimes two. I love when I go to southern California for work, and there are 12 lanes with almost no traffic (yes, traffic here is worse than there).

https://www.fhwa.dot.gov/policyinformation/tables/01.pdf

> If your powertrain is > 1.0, the tax you pay when buying cars has a sudden increase.

What do you mean? Engine displacement>1L? Transmission overdrive? Something else?

Engine displacement > 1L (in fact, > 999cm³).

Not sure if these values are still valid, but if they are not they should be even worse nowadays.

Made in Brazil: < 1L: 30.6% 1L to 2L - 34.6 or 36.6% (gas + ethanol) > 2L - 41.6% or 48.6% (gas + ethanol)

Imports: < 1L: 60,6% 1L to 2L - 64,6% or 66,6% (gas + ethanol) > 2L - 71,6% or 78,6% (gas + ethanol)

Also, immediate availability is lower and most cars are manual with no cruise control :(

And obviously you'd already be paying a little bit more for a more powerful engine, so the increase is actually at least 10%, and most lower income people just get stuck with 1.0 for their whole lives...

https://www.noticiasautomotivas.com.br/automovel-recolhe-de-...

At 112mph you’re traveling 54 yards (50 meters) per second.

There’s no situation that can be solved by increasing speed at this velocity. You simply won’t have the time to react. Unless, of course, you’re trying to outrun a train in a car chase in a movie.

You say that now, but when the old wooden bridge is out and the revenuers are hot on your tail, you'll curse the day you bought a car that was limited to only 112mph.

You might need to escape a tsunami, pyroclastic flow, forest fire, or hurricane. The road might not go in the ideal direction, so being just a bit faster might not be enough.

That sounds like an unrealistic fantasy that's fun to watch in the movies, but not likely in real life. Driving 130mph in a storm or forest fire is more likely to result in you running off the road (or into another fleeing vehicle) than getting to safety.

But if this is your fear, you should probably drive an off-road motorcycle so you have more options to get out of town when the disaster strikes, limiting yourself to the roads sounds risky.

> not likely

But it is an edge case.

There are lots of highly unlikley edge cases that one could come up with... like seeing a crashing aircraft approaching you from behind and if you could only go 5 mph faster you could stay ahead of it before it strikes the ground, while if you go slower, you'll be hit by it or its debris trail or slam into the debris.

These are not edge cases.

- In a forest fire or in a storm visibility is low, so you wouldn’t be able to drive at speeds over 112mph anyway (see any footage of people driving through forest fires).

- A tsunami’s speed doesn’t exceed 20-30 mph on land

- a pyroclastic flow moves at 100kmh (62 mph)

In any case these edge cases do not outweigh the lives (potentially) saved by capping a car’s speed.

Suppose the road leading you to safety is not direct. It is at an angle, for example 70 degrees away from the desired direction. You'll need to exceed 112 MPH to outrun that pyroclastic flow.

To escape the tsunami, you first have to drive down a road that runs along the beach. After doing that for a while, you may then turn onto a road that takes you away from the ocean.

Visibility is usually fine in a storm. Hurricanes have intermittent periods of severe rain and insignificant drizzle. Forrest fire visibility all depends on the wind direction, and is often fine if you aren't already surrounded.

Too many “suppose”s.

At speeds over 100kmh (62 mph) you gain only 36 seconds or less per 10 kmh (6.2 mph) of speed increase per 10 km (6.2 miles) of distance.

So, you need to be in a dire situation, already traveling at top speed, on a road that doesn’t lead away from danger, where ~30 seconds of time would make a difference.

That’s a lot of ifs and edge cases.

When reality usually looks like this: https://youtu.be/coPW6unxeY8 (a three-point turn before tsunami) or this: https://youtu.be/7J6O4HkKxlo (driving through a forest fire)

Sorry, i don't know how to put that politely, but it's fucking ridiculous. There is NO SITUATION ever where a speed of 180 kph is necessary to avoid an accident. Life is not a Marvel movie.

If I were automaker I'd consider allowing bursts above the maximum speed limit for a few seconds. ... Imagine if you drive near this software-limited speed and suddenly need to speed up a little bit more to avoid a dangerous situation. You simply can't. This may dangerous specially if you don't have in your mind that your speed is limited by software.

But imagine that you had this 5 second burst and you used it to pass a truck, but you misjudged and you actually needed 6 seconds so your car drops back down to the slower speed, that sounds worse.

I doubt my car can go much over 90mph on a flat road (if it can, it'll take it a while to get there, since even getting to 80 is slow), and I've never had a case where I felt a burst of 100mph speed would get me out of danger.

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