SjB's link: Incidentally, there is an exemption for models sold at a rate of less than 500 a year. Hence a 60 bhp Corsa must have ABS, but not a 350 bhp TVR. Funny old world.
Perhaps it's a special edition Corsa that they've only made 499 of?
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SjB's link: Incidentally, there is an exemption for models sold at a rate of less than 500 a year. Hence a 60 bhp Corsa must have ABS, but not a 350 bhp TVR.
Good.
Now I have a reason to get a 350 bhp TVR. Hope I can use it soneday.
IIRC US studies showed an increase in rollovers (presumably from that steering-while-braking capability) negated any accident reduction due to improved braking performance. More SUV's there though.
Be that as it may, my antipathy isn't based on doubts about effectiveness..
I just don't want the b***** thing getting in my way when I'm working on the brakes..
EDIT : Apparently that's incomplete. Earlier research in fact showied a statistically significant INCREASE in fatalities (which of course was ignored) but that has been superceded by more recent research showing no net difference in fatalities, but a decrease in non-fatal accidents.
There are significantly more run-off-road fatalities (offset by reductions in other fatalities) but they expect mandatory Electronic Stability Control systems (which I don't fancy fixing either) will address that.
I'd have thought its going to be difficult to do this research in the future because there won't be any contemporary non-ABS cars for comparison.
https://www.consumerreports.org/cro/news/2009/08/government-study-confirms-abs-effectiveness-but-mysteries-linger/index.htm
https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/811182
Edited by edlithgow on 03/10/2019 at 18:13
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Whether it is extra or not you should get it.
I knocked a child down (unhurt thankfully) at a crossing as my Punto without ABS skidded on a wet greasy road :-(
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Kenl,
ABS would have allowed you to steer round the child had you had the room, the time and the prescence of mind to do so in an emergency. It would not have made a difference to your stopping distance in the conditions you describe, indeed on some cars it woud have increased that distance.
The worrying thing about ABS is the vast majority of drivers who think that it is some sort of magic braking system that will forgive any mistakes the driver might make and prevent all accidents.
ABS will only benifit a driver who understands what it is there for and knows how to use it. It will not allow you to drive faster, brake later or follow more closely than you do now. A lot of people who think otherwise are in for a nasty surprise.
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ABS would have allowed you to steer round the child had you had the room, the time and the prescence of mind to do so in an emergency. It would not have made a difference to your stopping distance in the conditions you describe, indeed on some cars it woud have increased that distance.
Agree with the sentiment but question the assertion. A skid on a wet, greasy road as described is probably the one scenario in which ABS could decrease the stopping distance. If you had the presence of mind to apply optimal brake pedal pressure on a non-ABS car to not lock the wheels up you might stop quicker than one with ABS. Faced with an unexpected child in one's path, I suspect a lot of drivers may not - like Kenl who skidded.
Despite a number of earlier studies casting doubt over the effectiveness of ABS, the NHTSA 1998 test track evaluation of ABS on light vehicles (www-nrd.nhtsa.dot.gov/vrtc/ca/capubs/sae1999-01-1287.pdf) concluded:
"For most stopping maeuvers(sic), made on most test surfaces, ABS-assisted panic stops were found to be shorter than those made with best effort or full pedal applications with the ABS disabled".
For Kenl's scenario - wet asphalt in a straight line - ABS resulted in an 11.4% improvement. And I'd like to think ABS has advanced in the six years since the study was carried out.
Despite its technical advantages, too many drivers over estimate its ability to get them out of trouble. Conversely, I don't have ABS and tend to hang back in wet conditions knowing full well the wheels will lock if I so much as look at the brake pedal.
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Despite a number of earlier studies casting doubt over the effectiveness of ABS, the NHTSA 1998 test track evaluation of ABS on light vehicles (www-nrd.nhtsa.dot.gov/vrtc/ca/capubs/sae1999-01-1287.pdf) concluded:
"For most stopping maeuvers(sic), made on most test surfaces, ABS-assisted panic stops were found to be shorter than those made with best effort or full pedal applications with the ABS disabled".
Test conditions, with test drivers. Probably valid as such.
But people don't drive under test conditions, and most of them aren't test drivers.
Its not unknown for policy to address this difference, hence mandatory TPMS.
Very little benefit IF people checked tyre pressures, but they didn't.(Or at least, Americans didn't. I assume it was the same in the UK but don't actually know)
Just to reiterate, in the real world, (which is in America, according to Americans) the introduction of mandatory ABS killed people. .
Now it doesn't, and eventually they think mandatory stability control will allow it to save people.
Not really massive justification for the regulation, but regulations tend not to need massive justification, because they are, like, regulations.
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Most people just don't brake hard enough soon enough, ABS or no ABS. Or at all. And many don't steer - there is apparently a natural tendency for people to go where they are looking, which is usually the thing they are frightened of hitting.
Safest thing is to avoid the situation in the first place, which ABS has very little bearing on.
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Tom,
Mostly I agree, but an important point is the competence of the driver. A competent driver will, in some situations, be able to out brake an ABS car. However, I suspect that a huge amount of drivers would not have this expertise and tehrefore are better off with ABS.
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Mark,
Can't dispute your point that that ABS will out perform most drivers ability to use brake in an expert manner in an emergency, and I am not against the use of that technology.
However, ABS does not generally shorten the distance in which a car can actually stop, as stated it's function is to allow the car to be steered with the brakes full on. The problem is the widely held misconception that ABS brakes are some sort of foolproof on/off switch that will prevent you hitting anything as soon as you touch the pedal.
In the accident described at the start of the thread it is highly unlikely that they would have had any effect at all, as on a wet greasy surface the car would have probably gone in a straight line no matter what you did with the steering. ABS provides the driver with a marginal improvement in his ability to deal with an emergency in limited circumstances, but the technology that will really help him is sitting between his ears.
Hi-tech safety aids are to be welcomed, but we must not fall into the trap of overestimating their capabilities, and that is what seems to be happening re ABS.
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Ref Tom Shaw's scepticism about ABS - I would argue the probability that ABS does shorten stopping distances in the majority of cases where it matters - i.e. on a wet road where a skid would likely result from heavy braking, or fear of skidding might prevent the driver from braking hard enough.
Put another way, skidding on a wet road will vastly increase your stopping distance assuming you can avoid the ditch - if ABS prevents skidding I don't see how you can persistently state that ABS does not shorten stopping distances, at least in the real world.
Neither do I agree that many drivers think ABS is a magic spell. I do think that most people who are not car minded don't know the basic rule about using it - brake hard in an emergency and let the ABS sort it out - and may continue to brake too little too late for fear of a skid.
All of my family drive ABS equipped cars. None of them thinks it gives them magic powers and they all know how to use it.
ABS is a huge advance with few if any drawbacks as far as I can see.
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>I don't see how you can persistently state that ABS does not shorten stopping distances, at least in the real world.
Tom is of course correct to "persistently" state this.
Whatever the stopping distance in any scenario, ABS cannot shorten it.
It cannot bend the laws of physics.
Indeed, as Tom says, under some circumstances it lengthens the stopping distance.
The whole point of ABS is to give steering whilst braking heavily.
And yes - I have a pal who after (another) panic stop says
"Thank goodness I've got ABS". Excuse me?
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Whatever the stopping distance in any scenario, ABS cannot shorten it. It cannot bend the laws of physics.
Are you really saying that avoiding a skid will not reduce stopping distance?
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ABS does not prevent skidding.
Nor can it increase the grip of the tyres on the road.
It does not reduce, and could increase, the stopping distance on a slippery road.
(source of above:- Roadcraft)
It only operates during harsh or emergency braking.
It goes nearly lock - off - nearly lock - off.
Giving steering control.
Now, the problem of education, as Tom says, is significant.
If, as cases have been recorded, drivers panic when the pedal fights back against their foot
(or that's what they think), and lift off - smash.
It normally takes sevaral attempts to get the correct
"HIT pedal - keep it there - LOOK where you want to go - turn wheel there"
taught to people.
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It cannot bend the laws of physics.
And which law of physics would this be? The one that states frictional force is a constant? I think not.
I seem to remember that the coefficient of friction increases up to the point at which the two surfaces in contact start to slip against one another - i.e. at the point a skid begins. If ABS can achieve this - and I'm not saying it always will - then it clearly can apply more stopping force and hence stop the car quicker.
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Check if the rules say this applies to cars built after or registered after that date.
Then order one after that time without ABS - if it arrives without take it back, kick up a fuss, threaten to report them to VOSA, the EU, anyone. You will get one with ABS then! for the old price
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Tom, On a wet greasy road the stopping distance using ABS may not be shortened and this is also true under some ice and packed snow conditions but on a normal dry road the stopping distance is shortened and in some cases dramatically. The new golf stops some 20% shorter with the ABS than without and I am sure that many other cars also stop shorter with ABS. I suggest you put a survey type question on the Discussion forum asking for yes (shorter) or no ( no difference or longer ) to see how wrong you are. The early ABS was not so good but cars in the last 3 years or so have very impressive stopping ditances with ABS and as you say you have some steering left. Regards Peter
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Sorry, but it is impossible for the addition ABS alone to shorten the stopping distance of a car in ANY circumstances. ABS does not make the tyres adhere to the road any more than is already possible without it, and if the Golf with ABS stops 20% shorter than the one without then it has a different braking system.
Anything ABS can do a driver can do with his right foot. Please forgive me if I appear to be trying to talk down to you on this, that's not my intention, but it emphasises my earlier point that the function and purpose of ABS is widely misunderstood to a dangerous degree.
I keep repeating this, But ABS allows you to steer with the brakes full on because it prevents the wheels from locking. That is ALL it does. No one involved in it's development or manufacture has ever claimed otherwise.
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I disagree, the coefficient of friction is reduced when two materials slide against each other, and as the speed increases, the friction devreases. In fact this is the phenomina that causes juddering in everything from a clutch to damp fingers dragging over glass.
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Sorry, but it is impossible for the addition ABS alone to shorten the stopping distance of a car in ANY circumstances
Quite an assertion - "impossible"? Evidence?
I notice you've been making statements like this in the past:
www.honestjohn.co.uk/forum/post/?f=1&t=5292
"stopping distance is REDUCED when the wheels lock"
O-level physics tells me otherwise. After all, the same logic would suggest wheel-spinning like mad will give you the best acceleration from a standing start. Pay attention to the next F1 start and spot the absence of tyre smoke.
I've pointed you at US Department of Transport research comparing stopping distances between ABS and ABS disabled vehicles which directly contradicts what you say. Were they wrong? Please show me the study which overturns their findings.
>>I keep repeating this
As Mark Radcliffe once said - "repeat until true". Time to back up your assertions up with some real evidence.
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Sorry, but it is impossible for the addition ABS alone to shorten the stopping distance of a car in ANY circumstances.
So if 2 identical cars, (one fitted with ABS, the other not), were to slam the ankers on, are you saying that they will both stop in exactly the same distance? Don\'t think so.
Anything ABS can do a driver can do with his right foot.
Within reason, yes. BUT given a emergency situation, the car driver without ABS is not about to start pumping his foot on and off the brakes at the same frequency that the ABS electronics can do. Neither would that driver be able to release one brake caliper while the other three remain on - ABS can.
I have to agree with others here. In general ABS will stop you in a shorter distance than non ABS will. It\'s been shown on the motoring programs countless times - the one with ABS always pulls up in a shorter distance. Whether that be in a straight line, going around a bend, and in dry and wet conditions.
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I agree with DD and TrvorH - as soon as a tyre starts to skid its ability to retard the vehicle is reduced. If ABS takes the wheels right up to, but not beyond, the point of locking then the result will be the most efficient stop for that type of surface.
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Anything ABS can do a driver can do with his right foot.
Sorry, but I can't modulate braking pressure independantly on all 4 wheels 16 times a second. If I could I would also need four brake pedals....and four feet.
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ABS must be good otherwise they wouldn't have banned it from F1, i'm sure it will also get better in the future because 16Hz (I heard 15) isn't very fast.
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It's all been said. The arguments against ABS, unless you're Eric Carlsson on loose snow or gravel (and who else is?), do not hold water.
I'll stick with the ABS thank you, as I have since 1991. I've had moments "with" and "without" and I know which I'd rather have.
By all means educate on the proper use, and caution against over-confidence, but it is irresponsible to suggest or imply that people should not opt for ABS.
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May I refer all you gentlemen who "know" to page 80 of Roadcraft.
Which will confirm that which Tom has been saying.
Tom - Matthew 7:5
(Oh yes - I found the refer back to "Paul Ripley doesn't know what he's talking about" very predictable. If sad)
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Why do you keep quoting Roadcraft it does not prove anything.
If you lock the wheels it will take you longer to slow down. Just go out and drive a car, gradually apply the brake. Stopping force increases untill the skid when it suddenly decreases.
When you brake at any speed the tyre slips against the road to some extent, ie the car tyre goes very slightly slower than the car is travelling. The force slowing the vehicle will increase untill the tread on the tyre starts to slip beyond the point of maximum traction. Then the wheel can lock up, and stopping distances will be reduced with ABS.
Now, different tyres can have slightly different characteristics. Therefore if the ABS is set to work with tyres that slip the least before they start to skid, the ABS will come in too early for other tyres. I have experienced older ABS systems where i felt the ABS came in too early. Additionally, i have noted on older systems stopping distances have been increased where one front wheel has gone over an area of road with reduced grip while the other side has remained constant- ie one wheel in a puddle, or one wheel travelling over rough tarmac. Additionally the amount of slip at maximum traction will change as the tyre wears.
When a tyre is rolling over a road that is not perfectly flat, the force it exerts on the tarmac will not be constant as the car is pushed up and down by the bumps. A very good ABS system could take this into account and modulate pedal pressure to maintain optimum slip. I have not driven any up market new cars recently so cant comment whether these cars are practically able to do this now. I found the ABS in an x plate BMW 530d quite impressive. However, i was not particularly impressed with the stopping distance- my old Jetta 16v with uprated brakes and suspension (and no ABS) could stop much more quickly.
What matters whether you have ABS or not is that you know and respect your cars ability to perform an emergency stop from a variety of speeds, and your abilities as a driver to control the car in these situations. ABS can save the lives of people who panic and would otherwise lock up.
If a car does stop quicker if the brakes are locked, it means that the braking system is so feeble that it overheats when performing an emergency stop, meaning the stopping force it exerts is less than that of a locked wheel. If this is the case, then the driver is going too fast, and should slow down. But on any relativly modern car stoping from 70 mph, this should not be the case. I would not drive such a vehicle as everyday transport.
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If you go through any of my posts, you will not find anything which suggests I am anti ABS. If it was available on a car I was buying I would certainly opt for it. My point was that many, if not most drivers (I don't include any of those who posted in this, although we disagree) believe it to be something which allows them to reduce following distances and brake later because they have some magical braking aid which will forgive all errors.
As Older but not Wiser points out, both Roadcraft and Paul Ripley have emphasised the limitations of the system compared to the expectations of those who believe the above. It is a great safety aid, but in limited circumstances.
If I were buying a car for a son, daughter or any family member and ABS was an option I would include it, but if the extra cash was the maximum I could afford to spend I would instead send them on a performance driving course where they would learn survival skills that would help them survive in far more circumstances than a mechanical after - the - event device.
As I read somewhere recently, it is amazing the number of people who will spend money on some safety extra for one particular car, but will not spend the same amount to learn a skill which will last them a lifetime.
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We are not idiots. We know that ABS does not change the friction coefficient between road and rubber. ABS is intended to maintain steerability and reduce risk of skidding.
My belief, based on reading numerous articles over the years, is that the shortest stopping distince is achieved by appropriate braking technique. ABS will generally produce a longer stopping distance than the best technique, but a shorter distance than with wheels locked, when ABS will compensate for driver error. What percentage of drivers do you think can produce the best technique in an emergency - including the knowledgable and careful ones who encounter these situations so rarely because they usually avoid them in the first place?
Technical articles rarely mention trees. The shortest stop can be achieved by running into a large one. In these circumstances a slightly longer stopping distance and some steering are an advantage.
The fly in the ointment for us pro-ABSers is the oft quoted US/Canada statistic that ABS-equipped cars are more likely to be involved in fatal accidents. If we assume this is not caused by skewed sampling, then an attractive explanation is that drivers believe ABS gives them super-powers and drive more recklessly. If this is the case then the problem is ignorance , not ABS - and you could make the same argument against seatbelts and airbags, with which these cars are presumably also equipped.
The sooner we have a proper driving test, the better - it would solve congestion more cheaply as well.
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We are not idiots. We know that ABS does not change the friction coefficient between road and rubber.
You are right, of course, but the if ABS can modulate the drivers braking input in order to help maximise the frictional force that can be withstood by the two surfaces then it will shorten stopping distances. It is not guaranteed that it will as there will be brief periods during an emergency stop where the wheels will be sliding or where the ABS has released the brakes altogether. It is the average force applied during the deceleration that counts.
My belief, based on reading numerous articles over the years, is that the shortest stopping distince is achieved by appropriate braking technique.
Can you provide a link to one? The 1998 US DoT study says otherwise:
"ABS-assisted panic stops were found to be shorter than those made with best effort [...] with the ABS disabled". The only instance where it did not was on gravel. I don't drive on gravel that often but tend to drive slower when I do if only to avoid paint chips!
The fly in the ointment for us pro-ABSers is the oft quoted US/Canada statistic that ABS-equipped cars are more likely to be involved in fatal accidents. If we assume this is not caused by skewed sampling, then an attractive explanation is that drivers believe ABS gives them super-powers and drive more recklessly.
The results were also confused by the assumption that the new found ability to steer under braking with ABS guaranteed a safer outcome. It was pointed out, however, that there is a genuine possibility that the braker will steer into danger - be it a ditch, a tree or oncoming traffic - where the outcome could be a good deal worse than sliding neatly into the back of a stationary vehicle. I am not disagreeing with your "more reckless" attitudes point, however.
Oh, and Tom, etc - I'm honestly not disagreeing with your fundamental point of driver education. Just questioning the basis of some of your arguments.
But ABS allows you to steer with the brakes full on because it prevents the wheels from locking. That is ALL it does. No one involved in it's development or manufacture has ever claimed otherwise.
The first manufacturer I looked at - TRW Automotive, the "the world leader in anti-lock braking system (ABS) production, having produced more than 60 million ABS units since 1986." states in its ABS product brochure.
www.trw.com/extlink/1,,,00.html?ExternalTRW=/image...2
"The Anti-lock Braking System (ABS) [..] allows the brake pressures at each wheel to be modulated to prevent the wheels
locking, thereby maintaining steerability, and reducing stopping distance."
Don't let the facts get in the way, eh?
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TrevorH wrote:My belief, based on reading numerous articles over the years, is that the shortest stopping distince is achieved by appropriate braking technique.
Can you provide a link to one? The 1998 US DoT study says otherwise:
"ABS-assisted panic stops were found to be shorter than those made with best effort [...] with the ABS disabled". The only instance where it did not was on gravel. I don't drive on gravel that often but tend to drive slower when I do if only to avoid paint chips!
Trevor,
After a deal of searching:
www.adtsea.iup.edu/adtsea/TheChronicle/spring_94/a...m
of which a relevant bit is "...If a driver panics and is unable to perform the braking skill required, antilock brakes will back up the driver error. The car will stop in a shorter time period in comparison to brake lockup, but not as quickly as appropriate controlled, threshold, or trail braking techniques..."
However I am quite prepared to believe that, as this was written in 1994, ABS has improved to the point where it is now difficult for any driver to beat it which is what your 1998 US Dot quote suggests may have happened in the 90s. Roadcraft may disagree but I'm pretty sure advances and new techniques probably make their way slowly into Roadcraft as the police will want a high level of assurance before changing their advice and training.
I am certainly not putting any anti-ABS arguments here; I don't think the vast majority of even good drivers can reliably brake optimally in an emergency; even the frequently referred to limitations of ABS on gravel and snow, where a build up of material in front of locked wheels is supposedly better than ABS, is an irrelevance for normal driving in Britain where the incidence of anyone driving at any speed on those surfaces must be almost nil.
M.
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Trevor, After a deal of searching: www.adtsea.iup.edu/adtsea/TheChronicle/spring_94/a...m
However I am quite prepared to believe that, as this was written in 1994, ABS has improved to the point where it is now difficult for any driver to beat it which is what your 1998 US Dot quote suggests may have happened in the 90s.
From the same site dated March 4, 1998
adtsea.iup.edu/adtsea/resource%5Flibrary/abs%5Fart...m
[
The National Highway Traffic Safety Administration (NHTSA) says, "When used properly, an anti-lock brake system (ABS) is a safe and effective braking system. ABS allows the driver to maintain directional stability, control over steering and, in some situations, to reduce stopping distances during emergency braking situations, particularly on wet and slippery road surfaces."
Anti-lock brakes cannot compensate for driving faster or more aggressively, or maintaining unsafe following distances.
]
I think we are as one on this. The Paul Ripley/Roadcraft supporters' make a valid point in arguing for better driver training & education with respect to ABS but use misleading statements to back their case.
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>>>I think we are as one on this. The Paul Ripley/Roadcraft supporters' make a valid point in arguing for better driver training & education with respect to ABS but use misleading statements to back their case.
Agreed. And FWIW I thought the Paul Ripley column would have stood endless reprinting.
M.
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May I refer all you gentlemen who "know" to page 80 of Roadcraft.
I do not profess to "know" any more than you. I will, however, question statements made that defy logic, regardless of who makes them - especially patronising IAM types. But I am prepared to listen what Roadcraft says. I don't have one to hand. By all means quote what it says.
(Oh yes - I found the refer back to "Paul Ripley doesn't know what he's talking about" very predictable. If sad)
Don't make ludicrous statements in the first place and they won't come back to bite you/Tom.
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But ABS allows you to steer with the brakes full on because it prevents the wheels from locking. That is ALL it does.
totaly agree.but dont recall this being mentioned.Must have missed it.But as you say thats all it does.
--
Was mech1
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I think one of the biggest mistakes people make with ABS (when they're not used to it) is to remove their foot from the brake pedal once it starts oscillating and pulsing as they are convinced there is a fault somewhere. Wrong!! Keep that foot well and truly planted on the pedal and let the electronics sort it all out.
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Tom, as you have gathered a lot of people confirm that ABS reduces the stopping distance in most circumstances. Whilst some braking techniques may have outperformed the ABS systems of the early nineties the four wheel independent ABS systems are extremely difficult to beat and that is only in controlled conditions, lets face it most braking where the ABS kicks in is not exactly a controlled condition. Add to this the front/rear brake balance valve of a normal system and you just can not hold all four wheels on the point of not locking the fronts often lock whilst the rears are still turning and all four wheels locked causes extended stopping distances. I have spent many hours on skid pans even as a youngster at Fradley Airfield at the Dunlop skid pan in the sixties, I have instructed hundreds of drivers on several race circuits and closed rally stages so your assumption that ABS extends the stopping distance falls on deaf ears, I’ve tested these systems in all sorts of conditions and surfaces, Tarmac, Concrete, Grass, sanded surfaces, gravel, shale, wet, flooded, oily, and even frosty, icy, powder and packed snow and other than the gravel ( marginal ), icy ( interesting ) and loose snow the ABS out performed the conventional braking system and any techniques. To minimise the ‘controlled conditions’ aspect the drivers were signalled to stop by radio so they could not pre meditate the braking point. On another occasion when we were running a race experience day we tested ABS cars again using the public to drive the cars and other than the reaction time to hit the brakes, the stopping distances again showed that ABS generally reduces the stopping distance and of course the real advantage that the ability to steer around, or away from, the accident is retained. I do not think, as you seem to, that ABS users travel closer to the car in front, however when ABS first started to appear on production cars you could get a bumper sticker that said “ I can stop, can you ?.” That would not be due to fact the ABS vehicles can stop in shorter distance than non ABS cars would it. However some drivers I’ve sat in with regularly trigger the ABS particularly in the last couple of metres prior to stopping. This is not good practice and not what it was intended for. Regards Peter
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I do not think, as you seem to, that ABS users travel closer to the car in front, however when ABS first started to appear on production cars you could get a bumper sticker that said ; I can stop, can you ?.; That would not be due to fact the ABS vehicles can stop in shorter distance than non ABS cars would it.
www.hwysafety.org/safety%5Ffacts/qanda/antilock.ht...4
"Leonard Evans, a researcher with General Motors, reported* that antilock-equipped cars were less likely to rear-end other vehicles but more likely to have other vehicles rear-end them"
*Evans, L. and Gerrish, P. 1996. Antilock brakes and risk of front and rear impact in two-vehicle crashes. Accident Analysis and Prevention 28:315-323.
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Mandatory on new cars from 2004: ABS braking maintains the level of grip between tyre and road at close to the maxmum level achievable, sliding or locked tyres mobilise sliding friction which is at a lower level, thus as physics tells us, sliding tyres lead to longer stopping distances
True there is a finite level of grip that cannot be exceeded by any braking system, it is jjustthat ABS keeps you around 5-15% wheel slip where friction is at a maximum not at higher levels of wheel slip where it is lower
And of course you can brake and steer at the same time, try that with locked wheels!
UPDATE: ESC: All new car models launched from October 2014 on will have to be fitted with electronic stability control (ESC) as part of new European safety regulations.
The technology, which prevents skidding during sudden manoeuvres, will become mandatory for existing model ranges in Europe from 31 October 2014
Edited by Dr John C Bullas on 03/10/2019 at 12:05
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Yep, post was from 2004 so relevant at the time. Wonder how many lives the policy has saved since then?
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Mandatory on new cars from 2004: ABS braking maintains the level of grip between tyre and road at close to the maxmum level achievable, sliding or locked tyres mobilise sliding friction which is at a lower level, thus as physics tells us, sliding tyres lead to longer stopping distances
True there is a finite level of grip that cannot be exceeded by any braking system, it is jjustthat ABS keeps you around 5-15% wheel slip where friction is at a maximum not at higher levels of wheel slip where it is lower
And of course you can brake and steer at the same time, try that with locked wheels!
UPDATE: ESC: All new car models launched from October 2014 on will have to be fitted with electronic stability control (ESC) as part of new European safety regulations.
The technology, which prevents skidding during sudden manoeuvres, will become mandatory for existing model ranges in Europe from 31 October 2014
My spam radar has just bleeped re: the above. I await further posts from this person to see whether my fears are confirmed or not.
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It seems manufacturers of a small number of cars are exempt from many regulations.
Ever seen an airbag on a Morgan?
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A 2007 Hyundai Getz did not have ABS but did have airbags. I assume the 2004 ABS regulation applied to brand new models only.
I doubt if a Morgan could meet many modern regulations , especially crash testing. An ash frame is hardly high tech.
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I doubt if a Morgan could meet many modern regulations , especially crash testing. An ash frame is hardly high tech.
Think of it as a lightweight biopolymer microtubule array composite produced by iterative selective genetic algorithms run and tested to destruction at massively parallel replication levels over geological time.
Because that's what it is..
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I suspect the major problem wouldn’t be its intrinsic strength per se, but its consistency. One of the reasons the classic LandRover Defender had to be discontinued was because airbags were impossible to calibrate for it. With a high degree of hand build in the production process, it wouldn’t crash twice the same way, even under controlled, laboratory conditions. Repeated impacts with a concrete block, from the same speeds and angles, produced varying results, making airbag fitment impossible.
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Re Morgan (and others) being exempt. I might be wrong but isn't it old models that are exempt from some regs? There are some provisions that only apply to "new" models. Old models can soldier on without some features. Some Morgans for example have zero rollover protection
I don't know why this didn't apply to Land Rover and the original Mini so maybe there are volume thresholds or other considerations that kick in? Not least of course that most markets now demand higher safety standards and no volume manufacturer now persists with models for more than a few years.
As an aside the previous Volvo XC 90 was famously one of the oldest models in production but had a fantastic safety record.
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Ever seen an airbag on a Morgan?
www.autocar.co.uk/sites/autocar.co.uk/files/styles...d
Edited by badbusdriver on 04/10/2019 at 10:41
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I've never crashed twice the same way either. That must make me a classic....er....something....
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