Comment by swaggyBoatswain | Hacker News Reader

Comment by swaggyBoatswain | Hacker News Reader

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swaggyBoatswain

This reminds me of a time when I went to the grand canyon with some buddies. We stayed there for a few days. Then made the drive back to the airport to fly home

Along the way to the airport some asshat setup traps along the highway. These were boulders the size of soccer balls scattered along the highway. We don't see these coming as there's a car in front of us

Next thing you know that car in front is veering out of control. One of those boulders that hit his tires flies off towards us, but luckily we veer and it misses. That could've easily broken the windshield and killed one of my friends.

We end up having another boulder on the highway that pops one of our tires, and we veer out of control.

Had there been a semi on the highway, or we had veered off in the opposite lane, we could've all died that day. Luckily this wasn't the case

Our car was the 2nd of 3 cars that got into a boulder accident

We later filed a police report to the person who setup traps on the highway. I got a letter in the mail he went to served a year in jail for this

Was there no chance that the rocks were due to a rock slide, or was it out in the middle of nowhere such that it could only have either been put there or fallen off a truck?

There's a chance, I guess? And that's why you have a court system to settle these questions, instead of just locking people up.

Middle of no where. There weren't any hills nearby

things like this convince me that humanity is doomed.

A) your car was tailgating if you couldn't see those stones soon enough to stop before hitting one.

B) the asshat who placed those stones will do things like this the rest of their life, and/or will encourage others to do so. that kind of thinking doesn't get corrected, that kind of thinking learns how not to get caught.

> A) your car was tailgating if you couldn't see those stones soon enough to stop before hitting one.

That's not the case. At any distance you can't see the road in front of the car in front of you (assuming equal height cars).

As the OP noted "One of those boulders that hit his tires flies off towards us, but luckily we veer and it misses." - this could happen no matter how far away you are.

> At any distance you can't see the road in front of the car in front of you (assuming equal height cars).

Which is exactly why you should leave enough stopping distance.

> "One of those boulders that hit his tires flies off towards us, but luckily we veer and it misses." - this could happen no matter how far away you are.

It could, but you should be driving slowly enough and leaving enough space that you have time to react to it.

thank you.

there is always a car in front of you. always, unless you are the very first driver on the brand new road. keep enough distance from the car ahead of you that you can see the road surface far enough ahead that you can stop.

if you need to see in front of the car ahead of you to have enough stopping time, you are following far too closely.

The boulder was likely moving far slower than the car ahead and reasonable stopping distance assumes that your obstacle is the car in front of you not an hidden stationary object on the road.

I find it infuriating how much people ignore safe stopping distances but recommending excessively cautious behavior just introduces more chaos on the road.

Advocating for following at a safe distance introduces havok on the road? seriously?

[deleted due to factual error]

I always just count the seconds. When I was a kid in NZ we had a great public service campaign by an Australian racing legend, who told us "Arnly a fewel braiks the tew second rewel"

I guess my point is the safe driving distance is based on something that can’t stop in 0 feet. If something falls off a truck I’m behind I’m not going to come to a complete stop.

I grew up in NZ & moved to the UK. There's similar rules here as well, 2s normally, 4 seconds in the rain, 8-10 seconds in the snow.

Stopping distance at 65mph -> 525 feet

Probably want to get those brakes checked. Stopping distance from 65 MPH should be no more than about 150 feet. Reaction time at 100 feet/second will probably be another 100-150 feet.

The non-metric rule of thumb [0] gives 490ft for 65mph; same ballpark. This incorporates reaction and actual braking, not just the latter.

[0] https://en.m.wikipedia.org/wiki/Braking_distance

Regardless of what Wikipedia says, if you take almost 1/10 mile to stop at 65 MPH, either you or your car is doing something wrong.

Between perception and reaction time, you’re already at approximately 1.5 seconds. At 65 mph, that’s roughly 140 feet.

(Source - my Dad investigated hundreds of accidents. He taught me how to drive and we covered this math in detail.)

It wouldn't work for everything, but you can cut that time by preemptively reacting to conditions. Say you're going around a blind corner, you can start slowing just because your visibility is lower and you don't know what's over there. Or you can see cars who intend to move over several lanes at once and kamikaze into the lane ahead of you and slow down because you know that all the people in front of you are likely to brake due to this.

There are quite a few scenarios where I spot trouble before it happens and have an effectively negative reaction time with respect to whatever is causing people ahead of me to brake.

Yes, as I believe I said.

1/10 of a mile is a long distance. If you need that long to stop, you need to slow down. Might also be time for a new car or at least a brake job.

It would be foolish to assume your tires and brakes and reaction time are all functioning at peak capability all the time.

Also, if you need to get into another lane, that in the immediate moment it is safe to merge into it.

Plus, it helps give more leeway to avoid stop and go, which is the cause of phantom traffic jams.

150 ft + 150 ft so 300' ... in perfect conditions?

Are we straight and level? What conditions are the tyres in? Wet/dry/oil slick. Brakes in good order? Vehicle size?

I recall driving a fully laden 7.5T box van for my diabetic brother (diabetic, hence he couldn't drive the van) moving house. I followed along the A40 (Oxfordshire), UK) behind him and then he cut off down to a roundabout on a slip road - my lorry wallowed quite dramatically as I followed suit and came to a shuddering stop behind him. Luckily I had six large tyres. If it had been wet, I would have shunted him into a busy roundabout. I would have tried to hit a barrier instead but who knows?

As someone else said: "2 second rule". When you are my age you can even see it!

Ugh. Google preview result for “stopping distance at 65mph” is for some obscure vehicle.

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