Safe Speed Forums

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Gordon Brown saying I got the country into it's current economic mess so I'll get us out of it is the same as Bomber Harris nipping over to Dresden and offering to repair a few windows.

Chaos, panic and disorder - my work here is done.

http://www.wildcrafts.co.uk

I saw it one bank holiday last year, on the M6, one woman sat doing 50MPH in the middle lane, caused a tailback for about a couple of miles them once I was past her the motorway was relatively clear....

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

Looking a bit further afield ,the jam causing capabilities are inherent in most towns -how often do we notice a person or two walking down the centre of the pavement ,and whether by intent or accident ,move sufficiently sideways to block any civilised attempt to get ahead of them .
My theory is that it stems from old fashioned ingrained beliefs in the "Flat earth " society -i.e walk on the edge and be liable to fall off

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Maybe fairer to say "...caused by just one driver - being followed by several hundred who aren't keeping an appropriate distance..."?

And cue music from a kids TV program "It's Shaun & Jean the sheep" - "WE'LL FOLLOW BLINDLY ,WITHOUT A BEEP"

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

The explanation for this is really quite simple. I really dont know why people still "Investigate" it.

The point is that the relationship between highway capacity and average speed is more complex one than most might imagine.

The average speed at maximum capacity (Vehicles/hour passing a fixed point) is around 20MPH

Below this the relationship is essentially linear down to 0,0

Above it it declines as an inverse square of speed (In practace it doesnt decline that fast, but only because in the real world drivers do not allow adiquate braking distance separation at higher speeds. which is fine most of the time, but as you approach maximum capacity conditions multiple pileups become increacingly likly, especially in poor weather conditions)

This means that for any given trafic "Load" there are two optimum speeds. As traffic load increaces the diference between these two speeds gets smaller and it becomes easier for a bad lane change or sudden braking incident (or overtaking trucks) to force the bulk of the traffic to shift from one speed to the other, then it might shift back again hence the pulsing waves seen from CCTV cameras.

In extreem conditions these can pulse between stationary and quite fast (though only for a short distance)

If you are stuck in these sort of traffic conditions the trick is to resist the temptation to speed up when the traffic appears to clear. Instead, just stick to 25 or so and allow the gap infront to "Pulse" (IE when the traffic infront speeds up the gap will increace, when it , inevitably, comes to a halt a few minuites later yopu will catch up but if you get your own speed right it will start moving again just as you catch up with it)


You should only speed up significantly once you are certain that the road ahead has cleared.

Much less strsssfull than stop starting all the time.

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"The road to a police state is paved with public safety legislation"

Yes, it's what I tend to do, but you then have to live with life's "winners" in ther rep-mobiles, piling into the gap ahead of you (then having to brake suddenly) AND you have to suffer the aggro of the motorists behind you in the queue who fel you're only doing this to pi55 them off! As I say, I tend to do it, but there are disadvanages too.

Have a play with this for a few hours!

http://www.vwi.tu-dresden.de/~treiber/MicroApplet/simFrame.html

Take a chain, and lay it on the ground with the links pushed together. Then start pulling the end link, and see how long it is before the last link sets off after the first.
Variables are:
The length of the chain/links, how tightly they are pushed together, and how quickly you pull the chain.

Simples "Cheeps" !!

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

yep, that's a good way of demonstrating that if you slow traffic too much when passing a slip road, that it becomes a snarl up.

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

Like Mole -I tend to TRY and do that -but as he said -the minute some gap appears which you're not appearing to fill in the time scale they demand ( usually 1 second) , you get aggressively tail gaited ,then closely overtaken .Be of slightly aged appearance ,driving what members of this club deem to be an OAP vehicle and it happens more frequently along with the surfacing of "test the aged " screams ,when in practice it's vehicles of a certain marque that could do with some retesting/re educating .Perhaps some investigating into looking out for these surges and the "must get there faster" brigade ,could lead to a welcoming committee ahead ,to educate this lot - and by holding them up for a while ,make them realise the benefits of patience .( Radical idea -they could traffic police to do this job )( But wait -hey - that's getting blokes to make roads safer with no income -how about some nice cash generating cameras )

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Definitely allowing for gaps in front of you can where far up ahead it is beginning to become blocked, enable traffic to flow ...
expand this with everyone leaving good gaps, help cars to keep a higher constant speed as things become clearer and speeds continue to increase and so traffic flows faster and the block frees more quickly. So the higher the speed attained, the faster it can clear that area safely, obviously.
If driver used much more forethought it would negate all variable speed limits and cameras for any of this.
Better drivers are our safest road safety asset.

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.

I reckon this has a lot to do with brake lights .... the lights alone don't tell the driver behind how much pressure you've put on the brake pedal and seeing brake lights on a motorway does tend, I believe, to induce some sort of mild panic! (On my old Xantia, the light switch was in the pedal rubber which meant that the lights lit up before you started to slow down)
In other words, if I touch the brake, the driver behind will see my lights and begin to slow down. The driver behind him will do the same etc etc and before you know it everything's stopped.
This is why I try as a general rule never to show my brake lights on a motorway (unless in a real "we have to stop NOW" situation). The way I see it, if I do need to touch the brake, then i haven't been paying proper attention and, for example, have inadvertently started tailgating someone, or missed warning signs that someone's about to invade the space in front of me. Any thoughts?

Would you think an intelligent brake light system that fed back a 'percentage of use' or 'force' would help ? Interesting.
When I have been on motorways as soon as I see some traffic brake it has not always been a 'surprise' but from a 'developing hazard', and so I have usually taking prior appropriate action (leave bigger gap / pass / adjust position etc.,). If it is sudden and not from a prior info then I will brake to ensure I alert with the earliest possible warning of danger to those behind. As I rapidly assess the situation I will be off the brake as soon as I can, perhaps even off after the initial appraisal.
I agree there is a 'general' initial 'brake' which is I believe is mostly the right initial action, but it is important that people judge the risk and manage and act appropriately as soon as they can to communicate the appropriate message to those around them. I agree that some who are travelling by tailgating usually are 'in the thick of it' and have to therefore brake for longer and harder, as apart from anything else, they cannot see (too close to car in front reducing their visibility massively).
Clear messages are good. Over complicated one's may well not be, that will confuse people and so likely brake for longer and harder.
Many cars have their lights in the 'on' state, as you touch, the pedal this is right IMHO.
It is the assessment and judgment that is going 'wrong' after the brake is used, not the braking per se. Being able to pre-assess the developing hazard, and take all appropriate action. When surprised after the initial braking, fast and appropriate reaction is required, sometimes it is right that all stops or slows dramatically ... We can improve that knowledge of hazards, the ability to pre-act, act and motoring skills through education and guidance. Helping recognise the earliest warning signs is crucial to improve better braking habits.
Agreed.

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.

There's a lot of discussion on this topic going on around the world just now amongst "experts".

Already increasing numbers of cars do something different with their lights when a certain level of deceleration is exceeded - typically put their hazards on as well or flash their brake lights rapidly. The same experts are also trying to agree on a level of deceleration caused by regenerative braking on electric vehicles that should trigger the brake lights. (Some of them can slow down pretty quick when you take your foot off the throttle).

A chap I worked for some years ago had a really infuriating habit of standing on the brakes on the motorway whenever he saw the faintest glimmer of what could be thought of as a brake light on the horizon! One thing I can safely say is that he was NEVER guilty of tailgating (but was frquently a "tailgate-ee" ). He didn't seem to do it on ordinary roads, just motorways.

I'd quite like to see a second pair of brake lights that came on at (say) 0.5G deceleration (and still have them flashing at (say) 0.8G) but I don't know what the effect of that would be on a dark rainy night in fairly dense traffic wen you're following a bunch of cars at a distance. I think you'd probably just see a lot of brake lights but still not know if it was a few cars braking at 0.5G or a lot of cars braking at 0.3G!

My gloomy prediction is that this technology will be "leap-frogged" by radar anyway and all cars will just automatically lift off their throttles and apply their brakes based on signals from the cars in front .

Again , it's all down to lack of experience and " panic braking" when all you probably need to do is lift off the throttle a touch. Even though I don't travel on motorways much, you still see it on rural nsls where someone touches their brakes at every slight corner or dip in the road, when lifting off the throttle and selecting the correct speed would mean that no braking was necessary in the first place. Obviously it has a worse effect on motorways as the ripple effect can occur, but if everyone left enough gap and read the road several cars in front and behind, then braking on a well flowing motorway should be negligible.

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.