Safe Speed Forums

I hadn't seen the braking spreadsheet on this site before, but I think it assumes too much. The deceleration is assumed to be the same from start to finish (i.e. from the moment the brakes are applied to the moment the car comes to a halt, it's decelerating at 0.9G). I'm not sure there are many (road) cars that can manage that - especially with any kind of load in them! It also assumes a perfectly consistent surface (no dips, bumps, changes in surface material, gradient, bends, spillages etc). That might just about be fair for the lower speeds but by the time you get up near the "ton", you'll be looking for about 400 feet of the stuff!

I'd have thought the table might be prefaced with "theoretical, ideal...etc".

Also, this thing about seeing something at night. Presumably we need to define what we're talking about a bit better? I'm sure I'd stand a better chance of seeing a person in a high-vis vest than a fallen tree and I'm sure I'd stand a better chance of seeing the fallen tree than a mouse!

Sorry to have taken so long to respond... I only went away for a minor family emergency and come back to 6 pages of posts!!

The problem on the A595 between Barrow and Sellafield is that the road has never been widened in some parts since the nuclear site was put there in the 1940's.
For some parts the road is barely wide enough for two cars to pass - and therefore has a 40 mph limit.

On the few parts where traffic CAN pass, there is a rush to do the deed before the next narrow stretch - and consequently a couple of "short cuts" are far more heavily used than they might be if the road was engineered to cope with the volume of traffic.
The trouble is the road is squeezed into a coastal margin by the mountainous topography, and any engineering would have to be on a scale which would cause major upheaval for some time, as there are so few alternative routes.

My point about spirited driving was meant to convey that the speed on the Millom road, is not due to drivers wanting to beak the law for it';s own sake, but more a means to an entirely different end.

There is a campaign to have a bridge/barrage across the estuary and bypass Foxfield, and a long length of the road, which would at least go some way towards reducing the journey time, and as a bonus, could be used to generate power - but is unlikely to get off the ground in MY lifetime because of the economic AND environmental barriers!

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

Possibly; do you think he wasn't? (if it actually happened as described).
Perhaps that section of road was lit!

Again, you assume too much.
You also didn't answer my questions (including those you conveniently decided not to quote from that same post) - should we be reading into that?

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

The brakes on modern cars are setup to try to give stronger braking force when the brake pedal is first tapped, so for those it is a reasonable assumption.


All fair points, but chances are if you're on a road which can safely handle anywhere near 80 then I think these points won't be that significant, certainly in terms of changes in road surface, gradients or bumps/bends (driver should be responding to the latter ones anyway). I wouldn't do such speeds in darkness on roads I don't know well, not without 'aid' anyway. Unfortunately there's not much one can do about spillages, at any speed.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Sounds like it if we've got people like you who think doing 80 or 100 on them is a good idea.

how does 'knowing' a road help you travel down it quicker?

Most people I've spoken to who claim to "know the road" use their knowledge to increase their speed round blind corners.

One of the memorable quotes from that lady that killed the kid (kids?) in her car that was made before she set off for her mad drive across the countryside was that she could perform the journey in a quick time because she "knew the road".

Of course I know that different vehicles stop in different times, and that the driver may have some small effect on that.

So do you think it's a good idea to drive at a speed that means you can't stop for 130 yards when you have 75 yards of forward vision?

I hope that you are being puerile now.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

Highly likely that he just had his foot down and was relying on luck.

But Graball was speaking of "doing 80MPH in the dark on rural roads in the dark". Those roads are not usually engineered to that standard.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

Excuse me, we do have good duals and motorways out in the sticks you know.

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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.

I do apologise In these particular sticks a "rural road" is a fairly narrow single carriageway, frequently hilly and always twisty.

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

No, he REALLY does!

He was making the point with regard to the post above your quote that unless you know the whole story, it is wrong to make snap judgements based on our own experiences, without a full explanation of ALL the circumstances.

I'll leave Robin to fill in the blanks!

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

yes, we have many of those too, I was travelling a lot of them yesterday and even in the daylight and if you knew that nothing was on them, such as a closed rally stage, you would be hard pushed to even touch 40mph in many places.

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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.

Perhaps you had better tell the Germans to stop using their Autobahns after dark then?

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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.

Correct. "Not usually" yes, but some are. Perhaps they were on one of those few that could?

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Like I said (and he didn't acknowledge): I've used these at daytime speeds that would make his hair stand on end - in darkness.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Not quicker, just not as slow; there is a subtle difference here.
On a road you don't know you may be overly cautious because the hazards, there or not, are unknown. After a few drives you get to know if there are no potential for blind hazards crossing your path (concealed entrances, bumps etc).


That makes absolutely no sense; a corner is blind whether you know about it or not. So I don't believe you.


N = 1 fallacy, that doesn't mean everyone else does it.
Can you give a link to a report on that story, I don't know about this one.


Really? Please explain why you think it is "Highly likely"
Given the fact the chap in the described event was probably doing it everyday (well he did it 3 times in a row), his luck would likely should have already run out; so I reckon there were other factors at work (if it was a true example).

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

I assume you mean the various sorts of "brake assist" / "panic assist" type systems that are starting to make an appearance? These certainly help apply the brake pressure quickly - perhaps quicker and harder than a typical driver might in a panic situation, but from that to saying "it's decelerating at 0.9G from the moment the brake is pressed to the moment the car comes to rest" is too big a step for me! In my (admittedly limited!) experience of brake tests, the overall retardation isn't that linear!


All fair points, but chances are if you're on a road which can safely handle anywhere near 80 then I think these points won't be that significant, certainly in terms of changes in road surface, gradients or bumps/bends (driver should be responding to the latter ones anyway). I wouldn't do such speeds in darkness on roads I don't know well, not without 'aid' anyway. Unfortunately there's not much one can do about spillages, at any speed.[/quote]

I honestly think that as soon as we have to use phrases like "chances are", it only strengthens the argument for putting some more caveats on the page with the spreadsheet!

This afternoon, ALL traffic from the A595 was being diverted through Millom, as a milk tanker had overturned on the main road!
It is currently still being recovered, as it takes so long to get the recovery vehicle to the scene!

The A595 has a terrible accident record, and is unsuited to both the TYPE of traffic as well as the quantity.

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