Safe Speed Forums

I saw a very good example of the wave effect on roadworks south of Aberdeen recently. The temporary limit was 50mph but the average speed was more like 30-35mph fluctuating between about 10 and 40mph. The caussing factors seemed to be drivers not keeping a suitable distance in the first place and hence having to slightly 'overreact' when traffic slows (as pointed out furhter up the thread) but also drivers seeing the car directly in front of them pulling ahead and feeling the need to fill the gap appearing in front of them.

I was able to keep a steady 30-35 through most of the roadworks just by allowing the gap in front of me to grow/shrink.

In this case, keeping the same speed as the surrounding traffic (at least that in front of me) was probably not the safest option as the speed changes ahead were fairly abrupt at times.

You are never ever going to cure the wave effect it even happens at traffic lights.

While in a perfect world we would all leave the right gap between cars in practice every drivers judgement is different. How far ahead you can see through the cars in front of you varies as the road twists, turns and goes up and down it would be difficult to be constantly altering that gap to accomodate those changing views.

I like having lots and lots of acceleration available then I can leave a big enough gap to smooth out the flow and not have to brake but can then make up the gap quickly if it gets too big.

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Shooting is good for you and too good for some people.

This particular stretch of road lent itself well to this. It was on a long sweeping righthand bend so I was able to see about 20-30 cars ahead and could see the fluctuations in speed propagate through the traffic.

I agree, though, that it isn't always possible to damp out the 'wave' like this due to poorer visibility of cars ahead. I've seen lorries do this as well - easier for them as they have a better view of traffic further ahead.

Thanks. That seems about right. I guess those figure are national, equivalent to 60 (million) * 143 = 8,580 national road deaths each year. (I'm not saying the population then WAS 60 million - I am saying equivalent to)

It seems highly likely that the number of horses was hundreds of times smaller than the number of cars. And it seems highly likely that about 20% of the deaths would have been in London.

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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 have no figures to back this up, but I would have thought in the mid-19th century, for a UK population of maybe 30 million, there were around two million horses used for riding and pulling carriages and wagons.

A quick Google suggests the current UK horse population is 975,000.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

I seem to remember a quotation from early 1900 that said if the rate of horse traffic in London continued to increase then in twenty years time London would be covered knee deep in horse s**t.

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Shooting is good for you and too good for some people.

Whereas, in 2005, because it's the home of parliament, government offices and the head offices of the civil service, it's knee-deep in bulls**t instead!

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"Politicians are the same the world over... We build bridges where there aren't any rivers." - Nikita Kruschev

Extrapolating to today's equivalent:

Railway: 4560
Road: 8580
Drowning: 15060
Total: 28200

And those are all transport-related.
So we can safely say that cars save more than 20,000 lives a year.

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Only when ideology, prejudice and dogma are set aside does the truth emerge - Kepler

I had no idea the improvement is that huge: the most recent road safety data I have from the UK is 61 death per million population (Irtad 2003): so indeed road safety dramatically improved since the introduction of cars!

From Devon scammers' site:

http://www.devon-cornwall.police.uk/dcs ... edflag.htm



So speed limits (2mph) didn't keep deaths down then either.

By the way: what is going on in the UK?
Why are the fatal road casualties (per million) in the UK no longer going down?
You showed such a good trend since the seventies, but already in 1998 it was 60 per million, now in 2003 its is 61. You guys seem to suffer from a trend change starting at the end of the 90's.
What happened?

Bad road safey policy founded on false beliefs and speed cameras.

That's fundamentally why we're here.

Have a look at:
http://www.safespeed.org.uk/fatality.html
http://www.safespeed.org.uk/buckingham.html
http://www.safespeed.org.uk/againstcameras.html

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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

This is exactly what happens when the M25 variable speed limits are switch on. Within seconds / minutes a bunch or wave going back to standstill or very slow. Dangerous and once created it doesn't clear for some hours.