Road Safety, car design vs driver skill vs legislation vs cost benifit 2

[patprimmer]

A recent thread about some guy trying to justify disabling his ABS lead to the above topics being broached in an ad hock manner.

I have seen over the years many opinions and some statistics on the complex issues raised above.

I have serious doubts about some opinions and data, and wonder what the truth is.

I will throw up a bunch of open questions, or provocative statements to catalyse some discussion, and hopefully identify some fact and myth.

Regards
pat pprimmer@acay.com.au
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[patprimmer]

Driver skill training is an effective method of improving safety. Fact or myth?

I think I once read that drivers that attended driver skills courses (by whatever name is currently in vogue) show an initial reduction in accident occurrence and severity, but this diminishes within about a year until it comes back to the wider community average, however these trained drivers start to accrue an increased incidence of speeding offences.

If true, this would indicate that even though the accident avoidance skills are increased, the drivers eventually take this into account when allowing safety margins.

Regards
pat pprimmer@acay.com.au
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[GregLocock]

The Victorian police have always claimed that better training for drivers, in terms of handling skills, would be a bad thing for road safety. Oddly enough they send their drivers on these courses.

Personally I am not all that surprised. Few people have explored the adhesive limits of their cars, so are quite astounded to find how much dry grip is available on one of these courses. And once you know its there you tend to build it into your driving style, to some extent.



Cheers

Greg Locock

 

[jmw]

I think there are at least two seperate categories here:
1) the limits of the vehicle
2) road and/or traffic sense

Even a one day session with a very skilled driving school can be extremely beneficial. Some comments from a course i attended (driver skills, not vehicle limits)

a) there are no such things as "accidents" driver error always comes into it (including when the brakes fail, tyres burst etc due to failure to check the vehicle).

b) when people "learn to drive" they are actually being taught how to pass the drivers test, which is not the same thing.

c) most people stop learning once they have their licence.

But, a big question re the majority of drivers, would teachning or exposing them to the limits of their vehicles handling be a good thing or a bad thing? Do most people drive well within the safety limits precisely because they don't know what they are?

Incidentally, the British Police Driving Handbook was written for them by some very good racing drivers.

PS Greg, I wondered what on earth the Victorians could have to do with driving.... till i guessed it was a geographic thing, not an historical era thing!

JMW

http://www.viscoanalyser.com

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[mburgess]

I think that driver training for cars is something that authorities (here in Australia, others may be able to inform about around the world) dont really seem all that interested in. Has there been any actual in depth studies into the area. Standards for an advanced driving course that a student must actually pass. There are a number of good driving instructors around. They all have an extensive motorsport background. For motorcyle licensing In NSW the law was changes approx 10 years ago to restrict new (young) riders to less powerfull motorcycles, and they were required to attend a pre learners certificate training course & a second provisional licence training & assessment. This resulted in a significant drop in rider accidents & casualties in the young/learner age group. I do not see why a similar approach should not be taken to all motor vehicle licencing. Surely a better approach than a siple test to see whether someone can reverse park & use their indecators properly.
Regards,
MB

 

[Metalguy]

In Italy nearly ALL drivers know and have experienced the adhesive limits-many times. Sorta embarrasing when some guy blows past me around a curve in his stinking diesel (they all smell bad)station wagon and I'm in my Type R Acura Integra.

Can't blame it on an unfamiliar road,, 'cause I've been driving on it for 5 1/2 years now!

 

[GregLocock]

Some insurance companies offer lower (corprorate) rates if drivers are sent on defensive driving courses.

This makes the Police's attitude even more difficult to fathom.

By the way, engineers crash their company cars less often than most company car drivers in the UK, according to a recent survey.



Cheers

Greg Locock

 

[patprimmer]

Fitting devices to help maintain control, such as ABS brakes, better shocks, wheels, tyres and suspension design and settings etc is an effective method of improving safety. Fact or myth?

Do BMW M3's or Honda S2000's have a lower crash rate than SUV's or mini busses

I think I once read that drivers of cars with ABS show an initial reduction in accident occurrence and severity, but this diminishes within about a year until it comes back to the wider community average.

If true, this would indicate that even though the accident avoidance capability of the car are increased, the drivers eventually take this into account when allowing safety margins.

Regards
pat pprimmer@acay.com.au
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[harrisj]

Driver training includes why we should stop when tired, not drive when drunk, check our tyre pressures and a host of sensible things - not just about opposite lock and double declutching.

So of course it's a good idea - but where you draw the line at exploring the limits of your car is a moot point.

Greg's comment about engineers being safe is interesting - I perceive that most engineering colleagues drive quite fast but are more responsive to wet roads, stopping distances and closing speeds - perhaps the intuitive application of physics and Newton's laws of motion to the situation helps us. Or maybe we all found out the hard way in our mis-spent youth.

Having said that, I expect I shall drive into the car in front on the way home tonight!

John

 

[evelrod]

My opinion, based on having been a race car driving instructor for seven years in the late 80's, I found that being a good pilot on the track had virtually nothing to do with 'street' driving. I have always considered myself well above average when it comes to 'handling', re. finding the limit, etc.(I have the track records to prove it)! I also rode a motorcycle in the L.A. traffic for over twenty years and I can truly affirm that the ability to handle an auto in high speed conditions (as in competition) has little effect on the accident rate. As a matter of fact, some of the greatest race car drivers I have ever met tended to be rather inattentive at "slow" freeway speeds. As I posted in the ABS thing, I am prone to make the same "dumb" mistakes that are the cause of most 'accidents'. The difference, perhaps, is that should I find myself in a dangerous situation my ability would give me an advantage in getting out of it. That is an assumption as at 64 years old, I try very hard to NOT do the usual "stupid driver tricks". Like I said, I never met a driver that thought he/she was not "above average"!!!

Rod

 

[patprimmer]

Is there a correlation between car colour and crash rate, eg are metallic silver grey cars more accident prone than white, red or yellow cars

Regards
pat pprimmer@acay.com.au
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[patprimmer]

I think the result on seat belts and crumple zones are so conclusive that they need not be discussed, but how cost effective are air bags vs a very well designed and properly worn seat belt in a car with a very well designed interior re safety.

Is it possible to get people to wear seat belts in an appropriate manner for maximum safety

Regards
pat pprimmer@acay.com.au
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[patprimmer]

Are speed limits and speed limit enforcement effective in reducing accidents.

Do the vast majority of drivers show good judgement in assessing their best speed to keep them alert, but not get them into trouble irrespective of speed limits.

Germany might be the only country left where this data might be collectable, or the Northern Territory of Australia.

If speed limits more accurately reflected the realistic maximum safe speed, would they be obeyed much more often.

Enough for now, but I have a bunch more if interest is maintained

Regards
pat pprimmer@acay.com.au
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[evelrod]

To address the airbag issue, Pat---I had the unusual experience while standing on the corner of a major intersection in Pasadena, CA. a few years back when a small car ( A Neon, I think) made a let turn in front of a fast approaching Volvo. The hit just a few feet in front of me and I watched the passengr air bag in the Volvo deploy. The young lady (coming from her wedding and dressed in her wedding gown) stepped from the car shaken but totally unharmed. Made me a believer.

Here in the U.S. speed limits appear to be a revenue gathering device rather than any real effort at controlling accidents/traffic patterns. IMO. Around here the speed limit is 70mph but if you choose to do the speed limit you had better be in the SLOW lane!!!

Rod

Rod

 

[harrisj]

Rod

2 weeks ago I was driving down I-5 into San Diego and 65 mph was plenty fast enough. I found it quite scary. The hire car did not inspire confidence.

A month ago I was driving fron Hamburg to Hanover in a hired VW Golf at 170 kph in the rush hour and it felt just fine.

Back home in UK I'm happy at 80 - 90 on the M25 in fairly busy traffic. (This statement is of course entirely theoretical)

It all depends on one's frame of mind, the car you're driving, road conditions and the behaviour of other road users. Difficult to produce legislation to cope with that. (However, French autoroutes have a lower speed limit when the road is wet - 110 kph not 130 - it seems to work).

I'm afraid speed limits are here to stay - it's the Lowest Common Denominator effect.

John

 

[patprimmer]

Yes, but do the higher denominators fall asleep and crash because they are forced by law to be bored, sometimes to death

Regards
pat pprimmer@acay.com.au
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[evelrod]

Pat, that is why I chose to ride a bike to work when I was in L.A.---I couldn't stay awake on the freeways when commutes are in the 50 to 100 mile distance. Let me just toss this in for consideration---It would appear from the stats. that we have, that the majority of major accidents occur in off hours (if 'off hours' is possible in Los Angeles), ie, just prior to or just after peak hours (rush hour) and on weekends when traffic is lighter and speeds are higher. Drivers that travel the same route day after day at least know where they are going but the weekenders may not.
Just another observation---there are always "rear enders" during rush hour. Usually slower speeds. What I see in the last few years, perhaps due to the advent of ABS in the majority of fast cars, the rate seems to be less. Am I just imagining this??? What I do see is FAR more rollover and single car accidents!!!

John, at least in Germany you don't have to worry about the idiot passing you on the shoulder at 90mph, but even there my son gave up and parked his M3 and started using his R 650 or the train because of the horrilble traffic on the autobahn during rush hour. There are still a few western states in the U.S. where one can drive fast safely, but they are few and far between.

Rod

 

[jetmaker]

The issue of speed limits is an interesting one. IMO, a speed limit does not do much except help keep the general populus at a certain speed. The advantage of this is when changing lanes. However, I do not feel that it significantly lowers the accident rate. However, it does improve safety. Speed kills... that's a well known fact. I remember hearing that the German Autoban has very few accidents, but that when accidents happen, they are serious.

Another aspect is road design. I feel safer on a 2 lane divided highway than on a 6 lane divided highway. When there are only 2 lanes, you don't have many decisions to make, or worry about drivers cutting across several lanes at once.

Finally, the real threat to safety can be the safety devices themselves. People start to develop an invincible attitude when they have such devices. I have never liked ABS systems, nor traction control, because I find they take the control out of my hands. This makes me nervous, especially when I do not know how the system works or have an indication that it is working. And this is the problem, most people do not know how these devices work, and hence do not know their limitations. Take airbags for example. Do each of you know where the sensors are located? How many are there? What force, and from which direction, is required to set them off? Do you have to be moving for them to work? Same thing applies with traction control devices... such as the lag time for engagement, power transfer ratio, is it a wheel power limitation system, or does it apply braking to the skidding wheel? Also, how do you drive with these systems? In a skid, do you hit the accelerator, or back-off? (that may sound like an obvious question, but in my Jeep CJ7, once you got into the skid, in 4x4 mode, you needed to kick the gas to straigthen out; but in 2x4 mode, you needed to let off the gas).

If you question my issues here, next time it snows, look at how many 4x4s are in the ditch. Just because you have 4-wheel drive does not mean you can stop any faster.

Sorry for the ramble. For the most part, I like the safety devices, as maybe one day they will save my life. However, I would rather put the fate of my life in my hands rather than a computers, even if that means being a responsible driver.

Later,
jetmaker

 

[evelrod]

One of the things I observed in my students was that the overly aggressive drivers, the ones who thought themselves above average were the drivers who got the most out of the school. What you learn AFTER you know it all is most important. It's pretty easy to channel the agressive behaviour, re direct it in a productive manner, than to generate it from scratch.

Speed kills? Actually, no. It's the sudden stop that does the deed. If a SRS and ABS can diminish the sudden stop...?

To the issue of technology---I don't understand a thing about how this computer works, but it does not keep me from using it effectively. Likewise, it follows that it shouldn't be necessary to know how the safety systems on automobiles work in order to benefit from them. How much does the average driver, indeed, the "above average driver" know about what makes an automobile tick?

Rod

 

[jetmaker]

Rod,

Agreed that it is the sudden stop that actually does the majority of the killing, but regardless of braking system, it takes longer to stop at 200 kph than it does at 100 kph, so you will still hit the truck that pulled into your lane unexpectedly.

As for the issue of technology, I'll agree that your computer is one that does not affect you, but would you make that same statement for airline pilots who use autopilot systems, Global Navigation systems, Instrument Landing systems? Pilots are required to have a knowledge of how these systems work, albeit not the nitty gritty theory, so they understand their limitations, and can figure out when they are not working. I guess that maybe the reason people can and do take a laks attitude towards their vehicles is because the consequences of a mistake are not as severe, and the addition of alot of these systems just perpetuates the problem.

jetmaker