Safe Speed Forums

I think, like most things, these electronic drivers aids are both good and bad. I can find fault with all of them, yet I'm sure there are net benefits to many users in many circumstances.

Traction control is a very unfavouite of mine, especially when it's over sensitive. Too many modern traction control systems leave you dead in the water if you get a gnat's of wheelspin while pulling out into traffic. That's a no-no in my book. I also hate the way that traction control tends to be used to avoid the need for a proper traction system - usually a limited slip diff.

ABS is absolutely great if you need to brake with unbalanced grip left and right (e.g. left wheels on wet, right wheels on dry). But it's seriously horrible in some winter driving conditions - last winter was my first winter driving with ABS and quite a few times ABS seemed to inhibit the brakes altogether. I don't want to hear that ABS was delivering all the available braking effort - it simply isn't true. See figure 8, curve d on page: http://www.safespeed.org.uk/braking.html . With freshly fallen snow it's much much worse - more like curve c on the same graph. I'd like an ABS on/off switch.

Cornering brake control and various "stability programme" devices turn the car into wobbly jelly once the limit of grip is exceeded. I'd rather have a flick of the wrist and a dab of the power, thanks. But then most drivers haven't learnt to drive past the limit of grip on a circuit and / or a skid pan. They are probably better off WITH these devices.

Electronic damper control could be good - but I'd hate to catch the thing in the wrong mode just when I needed full control. I'm imagining a very urgent need for steering just after a gentle cruise. Imagine driving on the motorway with the damping on soft - then someone (maybe us) has a blow out and we need maximum handling to avoid a crash. Will adaptive damping adjust itself fast enough? Who wants to find out?

Any other electronic driver aids we should be discussing?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I think that ABS is all things to all men!

A couple of years I had the misfortune to own an ageing Vauxhall Cavalier, which I bought as a temporary stop gap whilst between cars, so to speak. It was my first experience of ABS and I was appalled! It used to cut in at the first hint of a adhesion loss, whereupon the pedal went right to the floor and the brakes seemed to come right off again. It certainly appeared to increase the stopping distance pretty dramatically over what I would otherwise have expected. I found I was really conscious of it's effect, and in slippery conditions I was quite apprehensive about how badly it was going to affect the braking performance.

But since then I've had three BMWs, all of which have had ABS, and it's a much less intrusive system that I can live with it quite happily. I accept that ultimate braking performance is probably reduced, but I think it's a pretty fair trade-off for the increased control and security I feel it yields in extreme conditions.

And to go to the other extreme, I've heard quite a bit about the ABS system on the Lotus Elise, which people say is so subtle that most drivers swear blind it's not working, yet it does.

Perhaps the ultimate would be a variable system, where you can control the amount of effect the ABS has with a rheostat on the dashboard, depending on conditions and "driver confidence"!

One other possible benefit though, is the effect it might have on ill-maintained / worn braking systems. Imagine a high mileage car where the rear brake drums have become distorted and are slightly oval. With a normal braking system these become the weak link in the chain, and the maximum braking effort you can apply is largely governed by the pedal pressure that (prematurely) locks the wheel with the oval drum. But with ABS, you can continue to brake harder whilst the electronics prevent the faulty brake from locking. Perhaps we'll see this as a fringe benefit as ABS filters down to "old bangers", though of course this effect will no doubt be tempered by the failure of the ABS system itself in those same cars!

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I stand to be corrected but I was under the impression that modern ABS systems did not activate at very low speeds. i.e. the sort of speed required to keep control on British snow. Older systems had off switches for use on snow/gravel since fully locked wheels are better on loose surfaces.



I have sort of had some experience with adaptive damping, more specifically the 'Hydractive' system on the Citroen Xantia. And yes it will react quickly enough.

The only problem I have with it is it conveys a false impression about the car's abilities. You have to override your instincts and push the car harder into a corner than the ride in soft mode suggests the car is capable of.

I would wonder what a person who has got used to having an adaptive system might do if sat in an almost identical car without it.

My car doesn't have any electrical nonsense, and I'm glad. But it looks like any replacement would have. In my line of work traction is always in demand and we don't use electrickery. That last thing we need when traction is at a premium is a cut in power. But that is off the road. I'd sooner spend the money on better tyres than gizmos.

On the road, just how fast do you need to drive before stuff like anti yaw control can have much effect? I'm sure the rolling police road block would have found you before then.

The on electronic aid I think is under rated as a safety device is air conditioning. Cool calm and collected must surely be the way to drive.

Certainly there are ABS systems that disengage themselves under 5mph. But 5mph isn't normal for out of town driving on snow. One long journey I did last winter on snow was mostly 40-50mph - and that wasn't "fast" - it was just a safe and appropriate speed selected by most road users.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Trouble is - lot of numpty people buy cars with these safety devices and simply do not understand how they work - and thus do not use them to max effect. They also think that these devices will kick in and save them from their own errors - without realising that their own skill and knowledge has to input too.

In a way - similar attitude as the prats with their speed cams ...

just realised the most effective safety device must surely be the speedometer. Watch that little clock and nothing will go wrong. Or so we are lead to believe.

If there is enough grip to travel at those speeds then there is enough grip for ABS to be effective.

That's not true - ABS is designed to allow only small amounts of "slip". See the graph I referenced earlier. Notice how the curves for packed snow and gravel (gravel and freshly fallen snow are similar) require large amounts of slip for greatest braking effect. See figure 8 on page: http://www.safespeed.org.uk/braking.html

Modern ABS limits slip to around 15% or under.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Yes, specially with modern cars, which isolate the driver from road sensation feedback and give a false sense of security.

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I've looked for data to support this assertion. One would expect that the smoothest quietest cars would be driven fastest and also have the greatest accident involvements. Right? But the opposite is true.

Then what about the developments of cars over the decades? Say between 1970 and 1990... Over that period the average car got an awful lot faster, smoother and quieter. Were roads fatalities increasing? Nope.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Fatalities may not have been increasing, but vehicle safety certainly was. So what about accident involvements that would previously have led to a fatality, but which is now surviveable? Have they changed?

Your numbers might not be so impressive when you include the proportions of pedestrians, cyclists and children.

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Try this:



And



From my unpublished work, based entirely on official data. (It's interesting to speculate about the risk transfer of seatbelt legislation in 1983 (1984 was the first full year).

What was your point?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Best data seems to indicate that every year crashes become 4% more surviveable due to vehicle safety improvements.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I wanted you to include proportions of pedestrians, cyclists and children in your numbers to see how impressive they were! I had understood that the proportion was growing. Very surprisingly to me, your graph appears to show a dramatic reduction in child and pedestrian deaths since cameras arrived. This is hardly an advertisement against them, so what is your point? It seems that we were right to bring the era of tyranny by cars to an end.

The child pedestrian rate has declined from around 180 in 1992 to less than 80 in 2002. Pedestrian deaths are going the same way. Even in the car data, the trend is clearly down since the 90’s. The uptick on your graph from 2000 (which agrees with official figures) appears to be the only basis of your complaint. It seems a slender case in the face of the increase in road throughput and overall drop in driving standards, which you have acknowledged. If you take your argument (that the death rate should decline linearly) to it’s conclusion, this would eventually result in thousands of resurrections each year! Is that what you expect? In any case, the gains in other areas eliminate this uptick totally.

Apart from this oddness, there has been steadiness or a gradual reduction in the death rates since the mid 90’s. Again, hardly an advertisement against cameras. Surely you don’t want to go back to the pre-camera and traffic calming days when 100s (that’s right, hundreds) of children from low-income families were getting killed by mindless speed merchants zooming through their congested streets? No Way Jose!

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Look again basingwerk. The reduction predates the use of cameras. For the cameras to claim the credit we must assume that something else was working to get the reduction up to the early 90s, and that whatever it was suddenly stopped working just as the Gatsos arrived. Also you mention child and pedestrian deaths. I don't see any age data on those graphs, so I'm assuming it's pedestrians of all ages, car occupants of all ages etc.
Tyranny by cars? Oh please, basingwerk, cars aren't tyrants. There's too many of them. There may be a fear of cars because people are forgetting how to live with their presence safely, but that would be quite different. On the other hand, since pedestrian deaths are falling perhaps any fear of cars is as irrational as a fear of spiders. You may be unlucky enough to come across a redback once in your life but it's really not worth worrying about the rest.
Again, you are crediting cameras with reductions that predate their introduction. How do you know exactly what had the effect? Without this knowledge it is hardly an advertisement for them.
Let's get away from the low-income bit, eh? Are you seriously suggesting that the death of child from a wealthy family is less of a tragedy than one from an inner city? I know that the stats show that children of low income families are at higher risk, but this is simply because they tend to live in cheaper housing which is usually nearer roads. Get 'em to swap houses and it'll be rich kids being flattened. All this low income stuff is irrelevant except to add a little more emotion to an already over emotive subject.
That rant over, can I ask where you get the idea that "mindless speed speed merchants zooming through their congested streets" are or were responsible for a majority of pedestrian accidents. Surely zooming through streets is nearly impossible when the streets are, as you say, congested. Even the government do not make that claim. Aren't they talking about 11-12% at the moment? In fact I don't even recall anything sensible claiming that it's even the biggest single factor. Failed-to-look and looked-but-didn't-see cause more problems, or thumb in bum and mind in neutral as you call it (which could apply equally to the pedestrians). Doesn't that mean that we'd be better off by getting these people, both the drivers and the pedestrians, to put their minds in gear? Especially the pedestrians as I seem to recall a TRL report that suggested something like 80% of vehicle-pedestrian accidents were largely the fault of the pedestrian. If this is anywhere near right then cameras are not going to help the local community in most cases. It might make them feel better, but for all the good it would do they may as well given all the locals a rabbit's foot each.

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I have, and the line is 45 degs straight from the early/mid 90s, tallying with the surge of interest in ending the era of tyranny by cars and continuing through the era of cameras with robust momentum.
You have a nice argument going there, Gatsobait! If a measure contributes to a rate of decline, you assume the decline would have continued without the measure anyway. This is along the lines of SafeSpeeds assertion that, once a decline is underway, it will continue (ceteris paribus) without further help. As if you could see into the future! This is not how the world works usually. Once the corrective effect is finished, that's the end of it and the slope levels off. To use SafeSpeed's example, look at seat belt in the mid 80's. No constant continuing decline there, eh? But why should there be? No, the effect you see in the graph is real, and corresponds with the period when we decided that motorists have to pay the full price of their activity, although they are still a ways short yet. But it is the continuity of the decline which is most compelling, and corresponds well with the increase in whingeing from motorists as the measures take effect.

No, I am seriously suggesting that the death in a traffic accident of child from an inner city family might be much more commonplace than the death in a traffic accident of child from a wealthy one. In a civilised country, the price of your parents poverty should not be death.

You'd be surprised how stupid some drivers are.



It's an uneven comparison - pedestrians aren’t wearing a two ton suite of armour. Your argument is akin to blaming the trees for de-forestation because they didn’t jump out of the way!

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Perhaps the older and more basic cars are usually driven by less well-heeled, less resposnsible etc etc impatient young people, whilst the more luxurious models tend to be driven by older, wiser, richer and calmer folk? I think these stats would make better sense if split into age and lifestyle groups.
Aren't there generally fewer children about? I heard schools are closing because there are not enough kids. Also car ownership has been going up and up, the evil things are everywhere now . I remember walking everywhere before I got myself a motor. Could it be that children and adult pedestrians nowadays make fewer and shorter journeys on foot? What are the numbers in % of child/pedestrian population at the time? How about fatalities per child/adult pedestrian-mile?

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So it is unsafe to say that people are driving better because the fatality figures have fallen. They may in fact be having more crashes (because they are overesitimating their own abilities and/or driving nice modern cars too fast for example) but surviving because of advancements in crashproofing?