Mastodawn

somedude

@ChrisMayLA6

It's the other way around, I think.

It's every bit as obvious as it is irrelevant that a slower speed reduces the overall chance of collision and mitigates its effects.

Never heard of a crash involving snails, after all.

And yet, there are a few places in the world, usually called a FIA grade 1 track, where a few elite athletes can push state-of-the-art machinery to 250+mph on a daily basis with no consequences.

This seems to suggest that
- the performance of vehicle and tires
- the training and fitness of the driver
- the type and condition of the road
- road rules
- the time of the day
- etc

might have something to do what a "safe speed" is.

In fact, unless the road is perfectly straight this speed will at the very least vary along it ("slow in, fast out" is how you navigate a bend, never the other way around).

The speed differential between object is also part of the equation (an object traveling at 300mph and hitting a still object is different than hitting an object traveling 299mph in the same direction and verse).

I'm an extremely conservative driver and rider (I've been called "boring" before), and I do think we are not doing nearly enough about safety.

Yet I'm extremely irked by the "speed limit crusaders": reducing speed or banning powered vehicles altogether is a certain way of reducing harm, but... in the same way in which starving is a great remedy for obesity.

- How many people drive around with shitty, dangerous and entirely random lines?

- How many people have no driving technique at all, and routinely unsettle the chassis when going into a bend?

- How many people can't brake at all and will slam the brakes without even trying to preload the front?

- How many people drive at a steady 1000rpm, with no control of their speed (whatever the idle + 5th gear is, really) and no engine brake available to them?

- How many people drive around casually chatting with and looking at their passenger instead of the road?

- How many people skip maintenance on their vehicles?

- How many people are driving around with ancient tires?

- How many people are trained to deal to navigate ice or gravel, the way every boring Scandinavian mum can?

- How many people DRIVE DRUNK?

Of course it's not an unpopular policy.
People like shortcuts.

But what if we could actually teach motorists to drive instead?

What if we could reduce antisocial behaviour at the wheel (texting, chatting, etc)?

What if we could have regular, mandatory training on lines, grip, maintenance, emergency maneuvers, etc?

Maybe we could (gasp) use powered vehicles to quickly, pleasurably and safely go from A to B, without everybody having to halt to a standstill because your drunk Uncle Grady or Aunt Karen just has to text while driving a 2500kg truck with 10 year old tires and no idea of what a proper line is or how to progressively brake.

@somedude @ChrisMayLA6

all right. But, still:

@amigaunicorn @ChrisMayLA6 Are you perhaps suggesting that making low speeds even lower isn't as beneficial as slowing down extreme outliers? :-)

@somedude @ChrisMayLA6

no. I am stating your own body has a mass. Speeding, it grows some kinetic energy. Once you stop suddenly, regardless of what everything else does or not all around, this energy will do some “work” on your body. That's it.

@amigaunicorn @ChrisMayLA6 Well, yeah.

Which is why having to stop suddenly amounts to a defeat for the sane motorist.

Stopping 30cm from a pedestrian or hitting the pedestrian is virtually the same.

You'd want to progressively shed speed as you get closer to a pedestrian crossing, a side road, a blind curve or whatever impairs your line of sight.

Alas, most motorists can't do a limo stop (i.e. going from 1mph to 0mph smoothly).

@somedude @ChrisMayLA6 pedestrian or not, changes nothing. This is the amount if kinetic energy your body hosts. Even if you crash alone, with no pedestrian or anyone else involved, this is the energy which will work in your body.

@amigaunicorn @ChrisMayLA6 I could have said "stopping 30cm from a tree amounts to hitting the tree", of course, but pedestrians crossing "out of nowhere" (yeah, my ass) seem to be the main challenge for distracted drivers, aka LBFTS or SMIDSY.

Sudden stops are bad.

Sudden stops are essentially crashes but for one small, random, epsilon of luck, as I said you want to have zero.

If you're having sudden stops of any kind you want to reconsider your driving.

The silver lining is that the G forces experienced by occupants of an ordinary vehicle in almost all controlled or semi-controlled (aka "ABS") stops can't do serious damage... unless we're talking Formula 1, where the drivers have huge necks to withstand the insane Gs.

@somedude @ChrisMayLA6 a teacher once told me "you can't talk physics". The point is, this is the amount of energy trying to do bad things to your body, you can't get rid of it, and it grows with the square of the speed.

Why should I add something? You can't talk physics.

@amigaunicorn @ChrisMayLA6

The point is, this is the amount of energy trying to do bad things to your body, you can't get rid of it, and it grows with the square of the speed. Entirely right.

Therefore, avoid shedding that energy all at once, because you can't talk physics :-)

Or do you propose getting rid of the Shinkansen just because there happens to be a whole lot of energy in that thing? :-)

@somedude @ChrisMayLA6

no. Nevertheless, I won't put millions of them on the streets.

somedude May 27, 2025

Eh, they're already there, that's the problem.
And they're crossed with oiler ships.

Horsepower in the 100s, weight in the double thousands (so you get a big m as well, although constant), wheelbase over three metres.

We can distractedly drive them at cycling speeds, thus engineering traffic jams everywhere, or demand that those who want to go slightly (slightly!) faster than cycling speeds approach them as the technical tools they are.

It would sadden me if we decided we'd rather have fat mums driving 3 metre-wide beasts at cycling speeds while tiktoking rather than just pedaling and shedding some of their massive weight, that's all.

I have a thought for you: if you think about it, civilisation can be characterised as the amount of energy (kinetic, chemical...) humans can safely handle.

Sometimes you have to accept that humans can't handle that much energy, because the human brain is limited in size; sometimes you have to strive for learning to handle it.

Where to draw the line?
No clear-cut answer, of course.

Uriel Fanelli May 27, 2025

@somedude

millions of hi-speed japanese trains on the streets?

uhm.