Following Distance - Free Stuff That Just Keeps Giving

[rastuscat]

When you are travelling at 50 kmh you are travelling at 13.8 metres per second. In 2 seconds, you cover 27.6 metres.

So if you are correctly applying the 2 second rule, you are 27.6 metres back.

The law only requires 20 metres at 50 kmh.

http://www.legislation.govt.nz/regul...DLM303092.html



I don't like to talk car lengths, as guys with Chev Impalas would be back over the horizon if they were 5 car lengths back.

When I run courses (or basically any time I get a chance) I run out a 20 metre tape measure. Anyone watching laughs, and says that nobody leaves 20 metres at 50 kmh.

Anecdotally, from my time riding Troll bikes, the average around Christchurch is 8 to 11 metres.

So, basically nobody follows the law, and yet we all know what the 2 second rule is. I have stopped people travelling 4 to 5 metres back at 50 kmh, and the first thing they tell me is that they were following the 2 second rule. Bollocks. Remember, the 2 second rule would see you back at 27.6 metres.

The next thing folk say is that if you leave a big (for this I mean legal) following distance, people just fill the gap. How dare they !!

But are we really competing with each other for space? Really? When someone fills the gap ahead of me, I actually don't find it hard to adjust to regain my space. Each time I do, I'm enhancing my safety and comfort zone. It actually takes pressure off too, when you keep distance ahead of you. I think of it as my space to soak up the driving errors of other people.

Further, I can quote a number of fatalities where the rider would still be alive if they had kept a decent following distance. And it's mostly not about stopping distance. It's about being hidden in the blind spot behind vehicles.

Again, you're welcome.

[James Deuce]

I tend to measure everything in furlongs and chains.

[rastuscat]

It will never catch on.....

It will when we evolve into competent road users. So you're right, it won't catch on.

[rastuscat]

Rastus,
A serious question. While I'm fine with the concept of 4m per 10km/hr speed,
how do you judge say 20 metre separation at 50km/hr ? Is the typical car
about 4m in lenth, so we say 5 car lengths at that speed ?

That's why I thought the two second rule came about, so as to make it much
simpler for people to open up an adequate separation distance from the vehicle
in front.

Cheers,
Viking

See my above re the 2 second rule. Everyone knows it exists, bugger all people understand it or apply it.

[rastuscat]

...is it safer to use imperial or metric measurements...

When you hit something the outcome is identical, whichever way you measure it.

[Viking01]

See my above re the 2 second rule. Everyone knows it exists, bugger all people understand it or apply it.

Rastus,
Thanks for the reply, and for the chart.

The point of my earlier point was simply "what do we use as a frame of
reference" to evaluate an approximate separation distance when driving.

I'm good with the two second rule, and tend to use it most of the time.
It's easy to apply, since all you need is to choose some fixed point at the
roadside and count.


It's just that since you posted an alternative method for evaluating a
suitable following distance, wondered whether it was a "better" method
(more reliable and easier to apply) and thought it worthwhile trying to
compare the two.

Your Method
Based on the chart that you provided, a typical car (plus its inter-car
separation) is about 4 metres. But then I'd have to try and estimate the
number of car lengths in front of me to the next vehicle, whilst taking
into account my current speed. Easier ? More reliable ?

Berries Method
I was intrigued by Berries earlier post (#8) regarding the length of a
white line stripe plus the separation between stripes. Are there some
specific rules that road markers have to apply when laying out such
road markings ? Can we then rely on them as a good guide to judging
inter-vehicle distances ?


No criticism intended. The scientist in me is simply now interested. And
I'm open to new methods.

Though I'll stick with the two second rule in the interim, as my old brain
can handle that without causing overload.

Cheers,
Viking.

[HEsch]

Aren't lampposts/telephone poles typically 50m apart? Something like that anyway...

[rastuscat]

Rastus,
Thanks for the reply, and for the chart.

The point of my earlier point was simply "what do we use as a frame of
reference" to evaluate an approximate separation distance when driving.

I'm good with the two second rule, and tend to use it most of the time.
It's easy to apply, since all you need is to choose some fixed point at the
roadside and count.


It's just that since you posted an alternative method for evaluating a
suitable following distance, wondered whether it was a "better" method
(more reliable and easier to apply) and thought it worthwhile trying to
compare the two.

Your Method
Based on the chart that you provided, a typical car (plus its inter-car
separation) is about 4 metres. But then I'd have to try and estimate the
number of car lengths in front of me to the next vehicle, whilst taking
into account my current speed. Easier ? More reliable ?

Berries Method
I was intrigued by Berries earlier post (#8) regarding the length of a
white line stripe plus the separation between stripes. Are there some
specific rules that road markers have to apply when laying out such
road markings ? Can we then rely on them as a good guide to judging
inter-vehicle distances ?


No criticism intended. The scientist in me is simply now interested. And
I'm open to new methods.

Though I'll stick with the two second rule in the interim, as my old brain
can handle that without causing overload.

Cheers,
Viking.

I'm sure that road markings are spaced to a standard, but I'm not sure what that standard is. If you can find a way to use the road markings, that's great.

But I just do it the simple way, counting off the seconds. I've been doing it for so long now that I don't even have to count, I am just used to what a good gap ahead of me looks like. I feel more and more claustrophobic the closer I get.

And that's the point. The more distance you leave, the more relaxed you can be.

[Akzle]

It will when we evolve into competent road users.

vote akzle.

i will have that shit enforced. violently.

and perhaps you could explain them road signs they have now... "high crash risk enforcement area" - so... they enforce a high crash risk? or the enforcement causes a high crash risk?

[Berries]

Aren't lampposts/telephone poles typically 50m apart? Something like that anyway...

No. Markings are to a specific standard so 'should' be 10m per set. Lamp columns are based on a lighting design and then tweaked to avoid trees, driveways and vocal neighbours. Wouldn't trust two to be the same distance apart.

[Berries]

Are there some
specific rules that road markers have to apply when laying out such
road markings ? Can we then rely on them as a good guide to judging
inter-vehicle distances ?.

Just Google MOTSAM part 2. I would trust the 10m thing but take everything else with a pinch of salt. Cats eyes are generally 20m apart on rural roads as well.

[rastuscat]

Just Google MOTSAM part 2.

I can't help thinking it should have been called Flotsam.

[AllanB]

I have a theory.

Modern vehicles have anti lock brake systems. Their drivers/riders know this. Thus rely upon it too much, as in follow close - anti lock will sort that shit.

[James Deuce]

I have a theory.

Modern vehicles have anti lock brake systems. Their drivers/riders know this. Thus rely upon it too much, as in follow close - anti lock will sort that shit.

You're putting too much thought into it.

[awayatc]

When you are travelling at 50 kmh you are travelling at 13.8 metres per second. In 2 seconds, you cover 27.6 metres.

So if you are correctly applying the 2 second rule, you are 27.6 metres back.

The law only requires 20 metres at 50 kmh.

http://www.legislation.govt.nz/regul...DLM303092.html



I don't like to talk car lengths, as guys with Chev Impalas would be back over the horizon if they were 5 car lengths back.

When I run courses (or basically any time I get a chance) I run out a 20 metre tape measure. Anyone watching laughs, and says that nobody leaves 20 metres at 50 kmh.

Anecdotally, from my time riding Troll bikes, the average around Christchurch is 8 to 11 metres.

So, basically nobody follows the law, and yet we all know what the 2 second rule is. I have stopped people travelling 4 to 5 metres back at 50 kmh, and the first thing they tell me is that they were following the 2 second rule. Bollocks. Remember, the 2 second rule would see you back at 27.6 metres.

The next thing folk say is that if you leave a big (for this I mean legal) following distance, people just fill the gap. How dare they !!

But are we really competing with each other for space? Really? When someone fills the gap ahead of me, I actually don't find it hard to adjust to regain my space. Each time I do, I'm enhancing my safety and comfort zone. It actually takes pressure off too, when you keep distance ahead of you. I think of it as my space to soak up the driving errors of other people.

Further, I can quote a number of fatalities where the rider would still be alive if they had kept a decent following distance. And it's mostly not about stopping distance. It's about being hidden in the blind spot behind vehicles.

Again, you're welcome.

I have to admit to completely agree with your whole post /point of view....

Apart from your statement that nobody follows that 2 second rule....
I will be goody goody 2 shoes, but that may be the only rule I always observe

So yes I will always allow for plenty of gap...probably more then 2 seconds most of the time.
And no I don't hang around. ...
don't necessarily obey speed limits
Got pretty powerful cages/bikes
And never had an accident yet in over 40 years on roads all over the world.

Because an accident means the gap has gone/become negative.....
I love my life to much to allow that to happen.


As an aside. ...Did you know that in the Netherlands the heaviest possible fine you can collect is for tailgating?