Safe Speed Forums

Here's where the "safe speed" argument breaks down, for most people.

(1) Driving provides a wide range of speed cues beyond your instrumented speed on the speedometer to which we are very sensitive: engine noise, road noise, wind noise, visual cues, accelerator position, etc. Once an absolute speed has been determined from inspection of the speedometer, that speed can be maintained within an error band for sufficiently long periods by exclusive reference to speed cues.

(2) The error band will vary from driver to driver, but in any case is unlikely to exceed 20%. The skills required to establish your personal error band is no more difficult than the skills assumed by adherents of so-called "safe speed" theory i.e. a "safe speed" adherent cannot argue that it is impractical without arguing also that his own theories are impractical. Anyone incapable of maintaining a set speed within 20% for short periods by reference to external cues lacks the necessary aptitude for controlling a heaving object moving at life threatening speed in a public space and should be prohibited from holding a license.

(3) To drive "safely" (in the sense meant by so called "safe speed" adherents i.e. in a way undistracted by the requirement not to exceed a given absolute speed), it is necessary therefore simply to drive to a lower limit which is the absolute limit less your own experience-derived error band. For example, a driver may choose to drive at 30mph in a 40mph zone, and 60mph in a 70mph zone. In this way, speed variations arising from the the driver's reference to speed cues can never result in him breaking the limit.

(4) Such a mitigation would only be unacceptable if the disbenefits of increased trip durations were greater than the aggregate disbenefits of road user deaths caused by increased vehicle speeds and the alleged distraction of attempting precision, instrumented speed control under conditions of externally imposed speed limits. In the worst (unachievable) case of a journey undertaken by an individual with a 20% error band entirely under the national speed limit exactly at a 20% average speed reduction, a 70 mile journey will take an additional 15 minutes. For representative journeys, error bands and average speeds, the same 70 mile journey will take an additional 5 minutes.

"Safe speed" arguments boil down to an argument that avoiding a theoretical delay of 5-15 minutes on a 70 mile journey is an important goal, for which disproportionate attention to vehicle instrumentation is necessary and dangerous.

We don´t agree.

Emvee,

You make a fair point. Since gathering my three hated penalty points I have adopted a robotic driving style. I look at my Road Angel speed counter every thirty seconds or so and I drive at around 10mph less than posted limits.

When passing speed cameras I drive even slower. I pass 30mph cameras at a 15mph crawl and always slam on the anchors when I see anything yellow by the roadside, a parked white van or a person loitering near a road.

Despite this uber concentration I was nearly caught by a red light camera last week as I was fiddling with my Road Angel and didn't notice the lights. At least I was only doing 22mph.

My wife isn't convinced that my new 'awareness' to speed has improved my driving as she seems less inclined to come in the car with me these days. I'm not sure how big a benefit I am getting from this new interest just yet, as I am tired a lot of the time and don't sleep well. My wife says that I call out about the 'the cameras!' in my sleep, and grip on to the duvet in a scary way.

Also when I am a passenger in another car I often get into trouble for shouting 'cameras!' every time I see an odd looking lampost, and distracting the driver.

A friend said - "It's driving, Jim, but not as we know it."

C.

1. As far as I can tell, your argument rests on the assumption that determining your speed very precisely is the crux of safe driving. My interpretation of the Safespeed position is that this is not the crux of safe driving, and that in fact this obsession with numerical speed is what's wrong with the last 15 years of road safety policy.

2. I take issue with your assertion that there is a relation between increased vehicle speeds and road user deaths. I'm not a great one for weighing posts down with stats and links, but I would say that IIRC:

a. The Dft figures show that only 4% of accidents are caused by breaking the speed limit
b. The US stats associated with reduction to 55 mph on Freeways showed no significant reduction in casualties
c. The imposition of speed limiters on HGVs caused no significant reduction in casualties
d. The impostion of the 70 limit on motorways, caused no significant reduction in casualties

So I'm afraid that we don't at first sight seem to agree.

I would be interested to see the evidence for the assertion 'most people', also who are 'we' precisely?

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

I have an issue with a couple of points here. You state that you should be able to achieve a 20% error band for a given target speed. This is all very nice, but the cameras only allow 10% + 2mph before you get done, and even then that is assuming that they are calibrated correctly. The main reason for that margin is to avoid zapping someone at 71mph and then have them argue that the calibration could have been every so slightly out. In practice it's possible to be doing, say, 74mph and get done for doing 79 by a camera that is operating within spec.

As for advising that people address this by doing 30 in a 40, 60 in a 70 and so on. Have you seen the chaos and congestion this causes, which in turn leads to frustration and could lead to another road user performing a dangerous overtake that puts both themselves and yourself at risk (especially if they choose to overtake without exceeding the speed limit and thus take 3 times as long). Not that all overtakes are inherently dangerous, of course.

Who are 'we'?

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Science won over religion when they started installing lightning rods on churches.

Your arguments that driving at a "safespeed" is flawed ignores all the facts.
Hundreds of people drive along thousands of roads labled 30 every day without sticking to this numerical limit and they dont die!

When you study those that do crash they are driving way in excess of a safespeed, not concentrating, drunk etc, etc
Pedestrians who die on the roads are often drunk, too busy listening to thier ipod or phone, not crossing at a safe place, jay walking on a motorway etc , etc.

most accidents have multiple causes, the prime or even secondary cause is rarely speed.

There needs to be a war on road deaths needs to focus on all the true root causes , not on one single issue which is a factor in less than 5% of road deaths.

I do not understand how speed cameras can be effective if cars are safer and speed cameras are saving lives... yet road deaths are not significantly reducing...

I suspect you are just a recycled old poster to this forum. can the mods please check

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

That's pretty much what people did in the past when speed limits were set appropriately. Sadly now many limits where I live (Suffolk) have been reduced to below the speed that even the slowest drivers travelled at. The result is that to follow your guidelines I would frequently be travelling at 20mph with just fields and hedges either side of me. Does that really seem sensible?

Oops

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Oops

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

If the "safe speed" argument breaks down for most people, why do most people break the speed limit?

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Political Correctness is a doctrine, fostered by a delusional, illogical, liberal minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.

Only if a road is straight, level and has a consistent well maintained road surface. Maybe it's fine in theory but breaks down in practice on real roads.

How was a road considered safe with a 60 or 70 limit now not even considered safe with even a 30 or 40 limit? Do you believe that all your ancestors from whom you descend were total idiots and unable to ascertain a sensible speed limit for a road?

Driving used to be a pleasurable experience in which one could take great pride. That somehow seems to have got lost in the last 15 years of potty policies.

The only logical reason I can see for the obsession with numerical speed limits nowadays is that the technology has become available to raise revenue from anyone who disobeys them. The more lower limits, the more revenue that gets raised. Where does it all end? 4 mph max with a red flag to be carried in front? We're nearly there already. So much for a hundred years of motoring technology and advancements with a government that seems determined to put us all back a century.

It is now often not possible to legally drive a car at its best MPG figure (normally it's around 56mph) on open NSL type roads so there isn't even a sound environmental reason to punish drivers in this way. In fact quite the opposite, it's as though the CO2 reduction target isn't truly of concern to this lot in at the moment. They may give lip service to it but there are no sensible actions to try and reduce it.

Without the benefit of speed limit signs, how do you know what speed to do under the following conditions:

1) going down a narrow street with parked cars both sides
2) passing a horse
3) going past a crowd of young kids playing on the pavement
4) going down your driveway
5) going round a street corner
6) going over a speed hump
7) going around a mini-roundabout

Or do you just assume that, as 30mph is the prevailing limit, 30mph is the speed you should be doing under these conditions?

Most drivers, most of the time, instinctively select an appropriate speed for such conditions, without reference to speedometers, limit signs or anything else.

The big danger of the current obsession with numerical speed is that it focuses drivers' minds on said numerical speed - often to the detriment of other far more important factors.

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

can i say it, please, please

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now retired

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now retired

Isn't this a rather exaggerated reaction to having gained a mere three points? And don't you find it seriously annoys other drivers?

Wouldn't aiming to drive at or just below the speed limit produce the same margin of comfort?

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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

Perhaps it is slightly exaggerated to make his point?

Quite!