A National Highway Transportation Safety Administration (NHTSA) study on Antilock Braking Systems (ABS) reveals that they’re not all that. In fact, the technology increases fatalities in certain circumstances. (Not that Frank Williams didn’t warn you back in 2006.) “ABS has close to a zero net effect on fatal crash involvements. Fatal run-off-road crashes of passenger cars increased by a statistically significant 9 percent (90% confidence bounds: 3% to 15% increase), offset by a significant 13-percent reduction in fatal collisions with pedestrians (confidence bounds: 5% to 20%) and a significant 12-percent reduction in collisions with other vehicles on wet roads (confidence bounds: 3% to 20%).,” “The Long-Term Effect of ABS in Passenger Cars and LTVs” reports [download pdf here]. “ABS is quite effective in nonfatal crashes, reducing the overall crash- involvement rate by 6 percent in passenger cars (confidence bounds: 4% to 8%) and by 8 percent in LTVs (confidence bounds: 3% to 11%).” That doesn’t sound . . . confidence inspiring. In fact, that nine percent increase looks even worse close up. A LOT worse.
From page 8:
But previous statistical evaluations of ABS have had ambiguous results. Analyses of data from the early 1990s showed significant increases in fatal run-off-road crashes with ABS, on the order of 28 percent. The increase was baffling, given the success of ABS on the test track. However, at that time, many drivers did not yet know how to use ABS correctly. During the mid-1990s, the safety community worked hard to inform the public about the correct use of ABS (“Don’t let up on the brakes”; “Stomp, stay, and steer”). A second generation of analyses circa 2000 showed much smaller increases in run-off-road crashes that were no longer statistically significant. But they were based on just two or three years of data and left uncertainty about the overall effect of ABS.
A nine percent fatalty increase sounds bad. A twenty-eight percent increase is an epic fail. But we’re not finished here:
On wet, snowy, or icy roads, where ABS is most likely to activate, the increase in fatal run-off-road crashes is a statistically significant 34 percent in passenger cars (confidence bounds: 20% to 50% increase). On these roads, all three types of fatal run-off-road crashes increase significantly for cars and so do fatal rollovers of LTVs.
WTF?
We are still unable to provide a convincing explanation or empirical evidence (other than the crash statistics themselves) for the increase in run-off-road crashes.
The aforementioned Mr. Williams reckons “I still think people don’t understand ABS, and when it starts pulsing and grinding they think something’s wrong and overreact. Maybe instead of spending so much money hyping hybrids, the auto companies need to do some commercials on how the safety systems in their cars work.”
So, is this a whitewash? The report’s emphasis on ABS’ net impact rather and statistical downplaying of ABS’ negative impact certainly should give NHSTA supporters pause. In fact, shouldn’t the NHTSA call for a moratorium on the technology?
But no, the report is suffused with reassurance that the next big thing in safety—federally mandated ESC (Electronic Stability Control)— will sort out the ABS “anomaly.”
Although the preceding analyses show a significant 9-percent increase for ABS on run-off-road crashes of passenger cars, the increase is small relative to the likely benefits of ESC. NHTSA’s 2007 evaluation of ESC, based on statistical analyses through calendar year 2004, found a 36- percent reduction in fatal run-off-road crashes. Thus, the combined effect of ESC and ABS is an estimated 30-percent reduction of fatal crashes.
So that’s alright then? Tell that to the families of drivers and passengers of vehicles where ABS was the difference between life and death, and not in a good way. Either that or just wait for the lawsuit.
Tell that to the families of drivers and passengers of vehicles where ABS was the difference between life and death, and not in a good way.
“ABS has close to a zero net effect on fatal crash involvements. The observed net effects are a 1-percent reduction of fatal crashes for passenger cars and a 1-percent increase for LTVs. Neither is statistically significant. But ABS is not without effect. Run-off-road crashes significantly increase while collisions with pedestrians are significantly reduced, as are collisions with other
vehicles on wet roads. However, the mix of these collision types among fatal crashes is such that the added harm and the benefits cancel each other.”
For every person who died running of the road in an SUV some kid running out into the street after a ball didn’t die. It’s a wash.
I won’t be quite as crude as jmo, but I have to agree that this report doesn’t seem to prove anything about ABS brakes being unsafe or that it “increases” accidents. My guess is that a lot of older drivers completely ignored the zillions of TV commercials, magazine advertisements, etc., that explained how ABS brakes work. The crash statistics should be cross-checked with the ages of the drivers, as I would expect that what it would show is that for drivers in younger age brackets ABS is a net benefit.
I think it’s quite simple: drivers do understand ABS, but they don’t understand driving dynamics. “Stomp and steer” spins you out, and that’s what’s killing people.
Add stability control on top of ABS, and then you can stomp and steer all you want. That’s the perfect combo. Before stability control was common though, what they should’ve done is warn you about using too much steering input or remind you that you could provoke a spin. Or give up on American drivers and market ABS as a straight line braking aid. You don’t actually learn what causes spins in driver’s ed.
jmo:
I won’t take the flame-bait. I know the horror of car accidents AND understand the value of natural selection.
Any new automotive safety technology should take into account human, uh, stupidity. (I think the technical term is “human factors engineering.”) If you have to educate people to use ABS successfully (i.e. no-lethally), then you should assume that the average person will not be receptive to that re-education. And when they’re not, “blaming the victim” indicates both bad science and moral cowardice.
In this report, the NHTSA flat-out admits that their track tests proved misleading. And they still throw their metaphorical hands up in the air.
This is yet another example where egg-heads miss the boat ’cause they forgot to apply common sense (and real world testing) to their data.
In this case, people died as a result.
Moral of the story? For some drivers, ABS leads to a false sense of confidence.
Cars don’t control themselves – drivers do.
I’m also unconvinced about the need for ESC systems in anything but high-performance cars or SUVs and trucks.
I’ve driven non-ABS cars for a couple of decades and ABS cars for about a decade or more.
Under certain circumstances, ABS is very MUCH more dangerous than non-ABS, but not always.
Briefly, I think that one culprit is stomp and steer. Clearly, this is simply the cheap and easy equivalent of state “education” in that it is intended for the typical mouth-breathers who don’t bother to understand the principles of driving a device that is deadly to themselves and others if misused.
The Germans and other Europeans have to actually understand the principles of how cars work, how they drive, and actually have to pass a very stringient driving test to obtain the privilege of driving.
jmo, I agree. The developed countries haven’t seen a major population reduction in more than 60 years. The natural selection pressure is so low that a lot of stupid genes still get passed down. With population growth at 1% in the U.S. and total population of 308M, this will change.
In this case, people died as a result.
That’s not what the report says.
““ABS has close to a zero net effect on fatal crash involvements. The observed net effects are a 1-percent reduction of fatal crashes for passenger cars and a 1-percent increase for LTVs. Neither is statistically significant. But ABS is not without effect. Run-off-road crashes significantly increase while collisions with pedestrians are significantly reduced, as are collisions with other vehicles on wet roads. However, the mix of these collision types among fatal crashes is such that the added harm and the benefits cancel each other.””
Again, for every idiot SUV driver who careened off the interstate in a blizzard and died, some kid chasing a ball didn’t die.
There’s something to this.
Most people are not going out testing their brakes in the wet, on loose surfaces, or in the mud. They don’t learn how the brakes react and how to get the best possible performance.
In my experience on slick mud or gravel ABS systems can get confused. I can pound the pedal down has hard as I want and I naturally won’t get lockup; a few times it seemed like I was getting very little braking at all – it took forever to stop. Threshold braking in the same conditions provided much shorter distances.
Go try it out… YMMV.
Maybe ABS alone doesn’t make a significant effect on fatalities, but when combined with electronic stability control it has a very large impact. Since most cars will have ESC soon and ABS is a building block of ESC, I don’t think this is that much of an issue.
BTW: Your airbags can also kill you if you sit too close to them.
If you look at the numbers it seems ABS increases fatalities among those who are being idiots – can you ever really die in a single vehicle off road crash if you’re driving in a reasonably safe manner? But, it decreases fatalities among innocent bystanders and those that are driving in a responsible manner.
That being case, overall ABS represents a valuable herd thinning technology.
The problem with these kind of statistical analyses is that they can never isolate a single cause, i.e. ABS, to a single effect, i.e. run-off-road crashes. At best, the analysis can show that a given cause does not result in a given effect. I wonder to what extent ABS and AWD (particularly in SUVs) leads drivers to a false sense of security? Here in the midwest, nearly every vehicle that I see run-off-road after a snow/ice storm is a 4WD truck or SUV, while us mere mortals in FWD cars recognize that we need to be more cautious when conditions turn bad.
I don’t know how I feel about ABS. The first time I ever needed it, it failed (the brakes did not activate) and I rear ended a stopped truck while I was doing 20. Another time I needed it and it saved me from extreme front end damage. Had to make a quick stop on a dirt/gravel strewn road to avoid an accident that had just occured in front of me.
I’m also unconvinced about the need for ESC systems in anything but high-performance cars or SUVs and trucks.
In Europe, ESC has made the most difference in the largest segment: short-wheelbase FWD family hatchbacks. Short cars can be harder to control in a bad situation.
The first time mine activated, the shaking startled me so much I about went off the road. Then I saw the “ABS” light flashing and figured it out. Might be the reason for the off road crashes.
John
What people don’t understand about ABS is that it doesn’t invalidate the laws of physics. If you are going too fast for conditions, you are going to hit things or have to leave the road to avoid them. The fact that ABS aids steering during braking, probably accounts for folks leaving the roadway, when in years past they would have skidded into the object they were trying to avoid. Proper education about the exponential effect on stopping distances presented by rain, snow, ice and vehicle speed will help folks realize that ABS is safety device, not a magic bullet.
when I first leaned to drive, my insurance agent told me a story about a situation with 2 choices, long story short – sometimes its better (and safer) to hit the dog vs. trying your best steer around it and taking the associated risks with that situation.
Maybe “stomp/stay/steer” (and ABS) has given people the confidence to try to get out of a situation that throws them into the unknow dynamics of grass/gravel/wetness off the road when the better answer is to slow as much as you can and let the airbags do their thing.
“On wet, snowy, or icy roads, where ABS is most likely to activate, the increase in fatal run-off-road crashes is a statistically significant 34 percent”.
“We are still unable to provide a convincing explanation or empirical evidence (other than the crash statistics themselves) for the increase in run-off-road crashes.”
Maybe I can help you out, guys.
Situation : Highway driver perceives need to stop in emergency situation but fails to do so, causing an accident.
No ABS : Driver hits brakes hard – skids straight into stopped vehicles. Whether they turn the wheel or not, same result.
With ABS : Driver hits brakes hard – ABS kicks in allowing some steering control. Driver turns wheel to avoid vehicles ahead. Given the choice between veering left into oncoming traffic or right into the ditch…voila – stomp and steer is the cause!
It’s only fatal if you look up from texting about the snowstorm on the highway and there are cars stopped 100 yards away while you are doing 60mph.
When ABS kicks in you are already in trouble. There is obviously no guarantee, that ABS will yank you out of trouble. The best defense is to drive without activating ABS (or need for pumping brake pedal if there is no ABS on a car). As one comedian noted: there is no fixin’ stupid.
JG :
October 22nd, 2009 at 10:49 am
There’s something to this.
Most people are not going out testing their brakes in the wet, on loose surfaces, or in the mud. They don’t learn how the brakes react and how to get the best possible performance.
I think you’re absolutely right. I live in Denver, so during the winter, my car’s ABS is constantly being used.
But what about some guy who lives in, say, Phoenix? Chances are the only time his car’s ABS will kick in is if he’s close to rear-ending someone. In that case, people stuff their foot into the brake pedal and hope for the best.
People really do need to educate themselves about how this system works to avoid having a false sense of confidence. ABS is a great safety tool, but it doesn’t give you license to drive like an idiot.
carlisimo :
October 22nd, 2009 at 11:03 am
I’m also unconvinced about the need for ESC systems in anything but high-performance cars or SUVs and trucks.
In Europe, ESC has made the most difference in the largest segment: short-wheelbase FWD family hatchbacks. Short cars can be harder to control in a bad situation.
How small are we talking here? I drive a Focus, and I’ve never noticed any special difficulty in handling it during emergency situations. Are we talking about micro-cars?
Sounds like the problem is that drivers don’t know how to drive; IE, they don’t understand that ABS will vibrate and pulse their brakes and try to pump them old school. That ignorance will disappear with time as most/all vehicles are equipped with ABS, and then the benefits from the technology will appear.
On paved road, I avoided a wreck last Spring by braking hard and steering around a suddenly stopped pickup. In the old days I recall doing that once and losing control of the rear end as the brakes locked up without ABS.
However I would be much more careful about doing sudden steering movements on grass, etc. I drive off-road often with a Jeep and it’s easy to tip and roll even at low speeds. It’s all about driver education, and as in mtr2car1’s example, I’d hit that poor dog!
I’ve always maintained that electronic stability control is 20x the safety mechanism that ABS could ever hope to be.
Well, FreedMike, if ABS is constantly being invoked during the winter then you have a problem.
Either the engineers have gone way overboard and had the ABS invoked way too early (which is possible if you have a US brand vehicle; the European engineers mock US spec cars for “parking lot speed ABS”);
Or you are driving way too silly-fast and reckless;
Or you aren’t using winter tires.
All-season tires are in reality only 3-season tires.
No guesses as to which season they’re unsuited for (and only slightly better than “summer” tires for)
I’m amused that the picture shown is of a Cutlass Supreme. I learned to drive in one of those things equipped with GM’s early ABS, and the brakes were a disaster. My dad bought it new, and by year 2 it needed a new ABS computer. Pads and rotors were done before 20k miles. By the time I got to it, the car was 10 years old. The very first time I drove it after getting my lisence, the brake booster failed, leaving me with a stopping distance that the Titanic could probably beat. The ABS was so flakey that it would often kick in when approaching a stop, even during mild braking and perfect road conditions, leaving me with no braking power. I wound up pulling the fuse and enjoyed more predictable stopping after that.
Oh, and even with a new booster, fresh pads, and the ABS disabled, the brakes didn’t have enough stopping power to lock up on a dry road. Dad said it had been like that since new, and the dealer told him they were all like that.
Partially because of that experience – and a sport bike that warped rotors if you looked at them funny – I’ve never rear-ended anything. I learned that you can’t trust your brakes to haul your ass out of the fire, and drove accordingly. The old adage is true: bad brakes make for good drivers!
I have no problem with the brake pedal vibrating during ABS operation – being a car buff, it’s something I expected before I ever even sat in the driver’s seat – but if it’s causing people to brake sub-optimally, why hasn’t this trait been engineered out yet? At worst, a brake-by-wire system would make it a non-issue.
ABS is a tool that you need to learn how to use. I started driving in 1993 and the first vehicle I had with ABS is my 2004 F150. I only buy used cars and everyone I’d owned before that, the previous owner either didn’t care or didn’t check the ABS option on the build sheet.
My father taught me to pump my brakes in panic situations but I have learned how to use my ABS, I think most drivers (because of our pitiful drivers ed) have no idea what the hell to do in a panic situation.
Who will save us from the civil servants?
People step on the brakes to stop. ABS adds distance. Not always is swerving the answer. Sometimes plain old stopping is what’s needed.
A lot of good points here, but one missed I think. Most people simply can’t make calm decisions under the influence of fear. If anyone has had experience teaching others a high speed sport with high risks (skiing, horseback riding/jumping, hoonish off-roading, etc…) then you’ll know what I mean. One or two people will pick it up as if born to it, everyone else settles into some plateau of competency, but when things get squirrely it’s only the first group that tends to pull it through. You could get every American on the roads to today to become a wet skidpad or ABS master on test tracks, and yet the percentage of people that retained the ability to do so when it mattered just wouldn’t be that high (it would help though).
I think MidLifeCelica has a reasonable explanation for these run-off-road situations.
I’ve only had the ABS system kick in ONCE, and it helped stop the car on wet road saving me from hitting another vehicle. However the vibrations are not very reassuring… I wonder how many people think the car (or brakes) are “broken” and lift off or do something else that causes the situation to become worst. Some on new Volvos and Mercs come with systems that detect (thru various sensors) that your not pushing the brakes hard enough to avoid crashing and increase the pressure for you, if this becomes mainstream maybe things will get better.
Personally I feel the brakes on most vehicles are no where near good enough. We all know cars are built to a cost and the automakers save a nickle wherever possible. The combination of “cheap” stock tires and undersized brakes means alot of vehicles are unsafe despite all their safety nannies. I’ve put larger/better tires on most of my cars and the increased grip is immediately noticeable, thus stopping distance is decreased.
I’m a driving instructor at car control clinics and do some track driving in a street car. One exercise we do with car control students is teaching them their car’s capabilities with ABS. It’s done in the dry if it is dry and in the wet if it is raining. Most people pretty quickly understand to wail on the brakes and to keep steering. But that’s not the whole thing. At more advanced levels, you don’t press, steer, and pray; that is the first thing you do. When conditions change you need to change what you are doing. If your car runs off the road, stomp, stay, and steer might be the wrong thing. At that point just steering may be the best thing. At the track, I’ve invoked ABS in emergencies but I lift when I drive off into the weeds since there are more effective things to do.
ABS is a tool, but not the do-all tool, for safety. The driver needs to do stuff too.
I have no problem with the brake pedal vibrating during ABS operation – being a car buff, it’s something I expected before I ever even sat in the driver’s seat – but if it’s causing people to brake sub-optimally, why hasn’t this trait been engineered out yet? At worst, a brake-by-wire system would make it a non-issue.
Pretty sure the vibration is there because that’s the best way to alert someone that they are losing traction. Would be hard to pull the accident avoidance maneuver if you had no idea you had to, the abs vibration lets you know you are slipping before it becomes painfully obvious and too late to avoid a collision. A light on the dash or whatever would be too easy to miss.
Side note, I find ABS on all 4 wheels to be very effective. I used to have a Focus, ABS on front wheels and now I have an Audi with Quattro, ABS on all 4 wheels. Both cars ride on Pirelli P6 “Four Season” rubber. Despite the Audi weighing about 600 pounds more than the Focus, it stops in about half the distance in snow/ice when I slam the brakes and the ABS kicks in. WAY more control than ABS on the front wheels only.
How about a study of 4WD increasing fatal-run-off-road crashes?
ABS can’t create any friction to increase braking ability. It can only manage the available friction. And keep the wheels turning to increase steering control.
By the way, I switched to an ABS equipped vehicle for daily driving three years ago, and I found it difficult to get used to it. The worst thing is, I don’t understand the vehicle dynamics with it intuitively. It’s not just a matter of seeing a couple of advertisements, it needs training, at least for people as dumb as I (of course I keep postponing getting to a clinic). This training gap may be something that professionals find difficult to grasp.
Pretty sure the vibration is there because that’s the best way to alert someone that they are losing traction.
It’s also great at communicating how much traction is available. If it’s just damp and you brake hard it goes thunk, thunk, thunk. On glare ice it goes whaaaaaaaaaa, ca-thunk, whaaaaaaaaam ca-thunk, whaaaaa. The father apart the “thunks” the less traction.
I’ve only had the ABS system kick in ONCE</i.
That would be the problem – you should at least take it to a parking lot on a wet or snowy day and see how it works. The time to learn isn't when you're about to head into the woods sideways.
I agree with autonut – The only time ABS kicks in for me is in the snow. I wish it wasn’t there sometimes. Should be a switch to turn it off.
I agree with autonut – The only time ABS kicks in for me is in the snow. I wish it wasn’t there sometimes. Should be a switch to turn it off.
Doubt that will happen…I can see the lawsuits flying when a family sues an automaker because the guy who hit their toddler had his ABS off.
Talking about turning off safety features…ESC is something that can be turned off. When I turn it off in my Audi, I can take turns in the snow rally style in a controlled sideways slide…When no one is around of course :) When I turn it back on, I can’t get the Audi to slide no matter what I do (going 50km/h), even in the thickest of snow. You would think ESC would be a standard companion to ABS if the intent of ABS is to help a driver turn and avoid accidents…ABS might help you start your turn to avoid an accident but during the turn it can’t do anything to stop you from sliding once you hit the gas during the avoidance maneuver.
The purpose of ABS is to retain steering control during heavy braking. Unfortunately, heavy braking makes the back end light so that it’s easier to spin out while steering. ESC helps to prevent that.
It’s well known that ABS increases stopping distances under slippery conditions. Audis used to have a switch to disable ABS under such conditions. I don’t know if they still do.
Question: What’s the most important safety component of an automobile?
Answer: The driver
Audis used to have a switch to disable ABS under such conditions. I don’t know if they still do.
Nope.
It should be noted that there are conditions where ABS can kill you … or at least fails to be of any benefit at all, but rather is a danger.
Last winter I was headed down a fairly steep un-plowed driveway in about 6″ of fresh snow. This in a 96 Scooby Outback, AWD w/ ABS, 5spd manual. I was going less than 5mph, idling in first gear. As I approached the end of the drive, I hit the clutch and the brakes to stop. The ABS immediatly engaged and I started to pick up speed !! Let out the clutch, and I slowed back to my ~5mph. Tried to brake again, and again started to pick up speed as soon as I clutched to disengage the drivetrain. Since I was approaching the main road with cross traffic, I yanked the e-brake handle. This locked the rear wheels, and since it is AWD also locked the front wheels. The result being I jerked to a stop in about 1 foot.
(edit – I should add that I’ve since been told that there is supposed to be a low speed cut off on the ABS to prevent this from happening. Obviously it didn’t work. I never want to own another car with some stupid piece of technology between me and my ability to control the car.)
Not being able to disengage ABS in deep snow is a dangerous flaw! I understand why auto makers don’t provide a way to do this. The average driver is probably too stupid to understand when to shut off the ABS.
I now own all non-ABS cars.
I live in a climate where snow and ice cover the roads for many days of the winter.
You would have to pry ABS out from under my cold dead foot.
ABS does stop in shorter distances on slippery surfaces because each wheel can brake according to the traction available to it. No amount of expert driver control or ‘brake pumping’ can hope to do this.
And like a previous poster noted, my ABS will be used to some degree on every day that I drive in icy conditions. First of all, I’ll do it purposely in a trivial situations because it gives me a feel for just how slippery it is. Secondly, it will happen when I hit particularly slippery sections of the road as I slow down. Obviously in these conditions I will always (so far) be driving conservatively to have extra stopping distance.
I will always choose more control over less, and I cannot ever see myself choosing to ‘skid helplessly because I don’t trust myself to steer safely’. And no, I won’t drive faster because ‘the ABS will save me’. ABS is not any more magical than 4wd is.
Anyone else ever manage to get their ABS going by unloading their car’s suspension as they’re coming to a stop?
I’ve noticed this while rapidly ascending off-ramps with significant ruts perpendicular to the direction of travel.
The experience is, uh, “awakening”.
Last winter I was headed down a fairly steep un-plowed driveway in about 6″ of fresh snow. This in a 96 Scooby Outback, AWD w/ ABS, 5spd manual. I was going less than 5mph, idling in first gear. As I approached the end of the drive, I hit the clutch and the brakes to stop. The ABS immediatly engaged and I started to pick up speed !!
Ever figure the reason you didn’t stop is because there wasn’t enough traction to stop you? If the brakes had locked you would have still slid down the driveway just with locked wheels.
http://www.chakpak.com/video/amazing-icy-car-crashes-in-portland-or-caught-on-tape/4512573
Just like these people – all four tires locked but still sliding downhill at increasing speeds.
ABS does stop in shorter distances on slippery surfaces because each wheel can brake according to the traction available to it. No amount of expert driver control or ‘brake pumping’ can hope to do this.
I grew up in a snow belt state, and I vividly remember learning that, regardless of how slippery the road is (or not), the fastest way to stop a car — period — is by locking all four wheels.
What ABS does, by comparison, is give you the maximum braking (per-wheel) possible without locking up the wheels, which gives you directional stability and the ability to steer (within the constraints of the available traction, of course.) Which is, of course, a good thing.
But there are lots of times where shortest-possible-distance trumps directional stability. So it’s kind of a wash.
This snippet of the report helps to explain what is happening with the numbers:
The great benefit for ABS, for LTVs just as for passenger cars is prevention of culpable involvements with other vehicles. On all roads, the reduction is a statistically significant 20 percent (t = 4.32; confidence bounds, 12 to 28%). On wet, snowy, or icy roads, where ABS is much more likely to activate, the reduction is a remarkable 36 percent (t = 4.79; confidence bounds, 24 to 46%). Here, ABS evidently enables drivers to stop in time and under control, avoiding vehicles in their own lane while not invading other lanes. The overall reduction of noncontrol group involvements on wet, snowy, or icy roads is a significant 19 percent (t = 3.10; confidence bounds, 8 to 28%) and the reduction of all crashes on these roads is 14 percent (confidence bounds, 6 to 22%)
What appears to be happening here is that accidents that would have involved additional vehicles are being replaced by one-vehicle crashes. Drivers are able to steer out of the path of other vehicles, but sometime end up off road, instead. Instead of wrecking another car and perhaps injuring or killing others, they limit the damage to themselves.
All told, that’s an improvement from the standpoint of the other motorists. That may not be so great for the driver in the crashed vehicle who may have been personally better off hitting a relatively soft Honda with a family’s worth of kids instead of a rather hard tree or pole.
Ultimately, ABS may do a better job of transferring damage back to the perpetrator, while helping to keep innocent bystanders out of harm’s way. That doesn’t sound like an entirely bad thing for those who don’t drive like nuts.
I can’t really use ABS to it’s full effect. I leaned at 16 to modulate (there was no ABS when I was 16) and that’s my instinct even today.
Watch this clip at the 4:00 mark
http://www.youtube.com/watch?v=j-hHWSQhKuc&feature=fvsr
For the most part, ABS will help you stop in snow. I certainly notice that in my Quattro. The Audi site itself does mention that ABS may increase stopping distances in gravel/snow in certain situations and I am sure that a non-ABS system might sometimes stop in a shorter distance in snow/ice but the car may end up stopping sideways like the car in the clip almost does.
@davejay:
That is simply not true. Locking the wheels is NOT the fastest way to come to a stop. This is because the coefficient of static friction (wheel rolling) is higher than the coefficient of kinetic friction (tire sliding). Just imagine moving a couch on a carpet. It takes more force it get it moving than it takes to keep it moving.
If the tires is still rotating it can apply more force to the road to slow you down, than a sliding tire. This is also why a burnout (spinning the tires) is not the fastest way to accelerate. This is the same principle.
A good ABS system will constantly monitor all four wheels and manage the brake pressure on each wheel to keep them on the verge of locking for maximum braking and shortest distance.
I taught myself to drive in a bog when I was 11 yrs old. I taught myself to threshhold brake in my 1st car with power front disk brakes. The whole trick to driving in slippery conditions is to not brake and to steer very gently. I even do it in my E150 work van. I’m sorry about about the steep learning curve involved. To quote B. Franklin ” Experience keeps a dear school, but fools will learn in no other.” P’raps the driver in the pic may have survived that puny roll over had (s)he been belted
In my 24 years of car ownership, I had 11 years of ABS in the middle period, followed by no ABS in my 99 Accord. During the period I had abs, twice it saved me from probable crashes. Both times I was going slowly, had an obstacle, hit the brakes, but the road was so slick the car kept going and I had to steer out of the way, but would have been skidding without ABS. Before I had ABS, and since I got the Accord, I have been extremely careful when there has been, or even might have been ice on the road.
My 05 xB has one annoying feature, related to the Vehicle Stability Control (VSC): Just as the car reaches the stability limit (wet off-ramp), a VERY loud beeping alarms, coupled with a dashboard light that flashes. It was so startling that I almost wrecked the first time it happened, because I thought something in the car had failed.
I’d prefer that a VSC simply step in quietly instead of frightening a driver who’s already very busy and possibly anxious about crashing.
As for ABS, it has saved me from a couple of crashes, and disappointed in others. I think having ABS would have prevented at least one of my accidents in the past.
I’m not sure what their report means related to fatal crashes. Airbags won’t save you, either, if your car falls off a skyscraper.
Maybe it’s just me, but if you hold your brakes, even abs, while sliding, your steering will be impaired. Perhaps the practice of LETTING GO of the brakes and letting the tires regain traction should be the practice we send out in that Safety campaine, as that is the one that works.
There is an unfortunate aspect of human nature that causes people to drive more unsafely whenever a new safety device is added to a car, so that the safety device ultimately makes us less safe.
Similarly, as foods with half-the-fat come out, people eat twice as much, and just a little more, and become more fat than they were before.
Also counter-intuitive, yet true, women today have access to very effective birth control, but we get pregnant “on accident” in higher numbers than our great-grandmothers did.
Of course I approve of ABS, low fat ice cream, and birth control. If only we could resist the urge to negate the value of these things with idiocy.
I recall reading an Australian Motoring magazine article that test drove a number of SUV’s (Toyota Kluger, Ford Territory, probaly Nissan Navara’s and Toyota Rav 4’s ) over bitumen and gravel/dirt roads. They managed to roll the Kluger on the dirt. They questioned the setup of the ABS/ESC on the vehicle and might have mentioned the word “dangerous”. Toyota immediatly fired back that the drive sequence wasn’t valid as it didn’t follow the standardised lane change/ swerve manouvere as laid down in the appropiate standards. Therefore the charge of “dangerous” wasn’t applicable and was considered slanderous. The magazine defended itself by pointing out that the standard swerve/lane change manouver was not the point of the drive, but a real world situation of, speed, enthusiam and gravel/dirt roads. With advertising of the systems as “life saving” the magazine noted that a lot of qualifications should be noted along side this statement, i.e. these systems do not repeal the laws of physics. You do something stupid and you’s better be aware of what you are capable of doing, not entrusting the vehicle to save you in all situations. Toyota went quiet after that.
Personally, I don’t like ABS. I don’t get why no car has ever featured a button to disable it like you have for traction and stability control. Some people, probably the majority like the system, but why no button to turn it off. The ability to have more steering input while braking doesn’t offset the huge decline in stopping you get in the conditions were the system is used. I pull the ABS in the winter after taking out a bush because ABS engaged on a slightly slick road at about 5 mph, and the car went way further than it would have without. I even compared stopping distances when the parking lot were I work was a bit icy. I went up to 15, and hit the brakes when I reached a door on the building. With the fuse in and ABS working, the car went about 2.5 times as far as without.
Here’s a situation I encountered in a 911, Boxster, and Lex RX330:
Hard braking on a very bumpy Michigan road, to the point that one of the tires gets nearly airborne and breaks traction, seems to confuse the ABS system to the point that the ABS module releases brake pressure to the wheel that temporarily lost traction.
You’re still slamming on the brakes but one or two wheels are not braking at all. It was always the fronts for me.
Scared the hell out of me. I’ve found that instead of waiting for the system to catch up, I can brake quicker by releasing and reapplying the brakes quickly.
These are new systems on nealry new cars and they get confused. Older cars are surely worse.
Not a big fan of ABS here.
To me this seems to forget several things that happened during/after those mid 90’s years. The proliferation of digital distractions. ipods, cell phones, gps nav, tv stuff, texting.
What I see when I am stopped for construction on hwy is someone oblivious in my rear view mirror barreling down on me. The only reason they ‘woke’ up was because I was watching and flickered my brake light. This person has already closed the safe braking distance and is no longer in braking thought pattern but in a avoidance (flight) maneuver heading down the ditch into the trees at 45+ mph.
my .02.
Another Drudge worthy misleading headline. The headline makes it sound like ABS technology is responsible for a net increase in fatal accidents, but the underlying article doesn’t actually say that at all. jmo is right in his observations.
A better headline would be “The Promise ABS Technology Shows on Test Tracks Doesn’t Show Up In Real Life, Mostly Due to Poor Driver Education”.
“I vividly remember learning that, regardless of how slippery the road is (or not), the fastest way to stop a car — period — is by locking all four wheels.”
Not true at all. The point of maximum braking occurs just before locking up the wheels, not after. This was demonstrated very effectively (sans ABS) when I took a one day driver training course at Sears Point many years ago.
@chaparral66
You got it sir. Why was this ABS system created? Because there was room for improvement.
This need not apply to older or poorly set up ABS systems. I can see how they can be more dangerous. But physics is physics.
Point here is that you should know and service youre ABS like you would your breaks and tires. If your not happy with how the ABS operates I agree the driver should be able to disable it.
I’m generally wary of ABS…
On very icy roads I’ve had it basically turn the brakes off, to the point where letting off the brake a bit to disengage the ABS is necessary. In other words, it doesn’t help much in poor conditions in my experience but it doesn’t hurt much either.
It also gets confused when all dour wheels lock up at the same time (again, ice) and it figures the car must have just stopped so the ABS doesn’t activate. When you are expecting ABS and get four locked wheels bad things happen. I’ve never seen this happen at speed, only crawling around towns that are skating rinks for much of the year.
2 wheel ABS on trucks is a waste of time and in my opinion dangerous… Someone jumping into one of these trucks can get mislead that it has 4 wheel ABS and stand on the brake pedal when they feel it kick in.
Teaching threshold braking to motorists (like motorcyclists are taught) would probably improve things by more than a statistically insignificant amount.
@ chaparral66
I’m not altogether convinced by your explanation.
As I understand it, ABS systems are calibrated in such a way as to enable the highest suspension compression into the tyre such that the contact patch area is increased. It’s this that gives the highest retardation performance.
The opposite is true for “burnouts”. The contact patch decreases dramatically as the tyre centrifugally expands. Ever watched a dragsters tyres? Interestingly, this is the principle of low rolling resistance tyres – the contact patch reduces, but can increase on braking.
If I turn the ABS off in my rally car (ST205 Celica GT4), my breaking distances are shorter, but I increase the chance of hurting the tyres.
Ultimately, ABS is about steering control, not absolute stopping distance. ABS increases the stopping distance on all surfaces.
@ Pch101
For what it’s worth, I agree with your interpretation (for a change!).
jmo : Ever figure the reason you didn’t stop is because there wasn’t enough traction to stop you? If the brakes had locked you would have still slid down the driveway just with locked wheels.
He probably figured that ABS is a disadvantage when it comes to stopping on snow and dirt, because it is. On a soft surface, allowing the tires to lock up and dig in reduces stopping distance.
John Horner : A better headline would be “The Promise ABS Technology Shows on Test Tracks Doesn’t Show Up In Real Life, Mostly Due to Poor Driver Education”.
Of course, educated drivers wouldn’t be trying to brake and steer at the same time anyway.
@PeteMoran:
So lets look at your theory. You are saying that the ABS is calibrated to compress the suspension to the point to increase the contact patch. Lets say that this is true. What is the point of maximum contact patch area? The contact patch size would only increase if there is an increase in the vertical load of the tire. What would increase the load? Well on the front tires, the load would increase as you are increasing the amount of deceleration (or acceleration if you want to be technically correct). So the point of maximum contact patch size would in theory be the point of maximum braking capability. So you are saying the same thing as I am. The rear tire contact patches would decrease during braking, because how would they all increase under braking?
No, if you are doing burnouts, the coefficient of friction is kinetic, the same thing if your tires are sliding under braking. Since kinetic friction is lower than static, in both cases the maximum force the tire can apply to the road is achieved if the tire is moving at the same speed as the road. The phenonomon that you are mentioning do exist, but have a very small influence compared to the differences in friction. Just imagine doing a burn out in first gear. Lets say say if your not spinning your wheels, first gear will redline at 45mph. So if you are doing a burnout your tires will be spinning at the same rotational speed as they would be if you are driving at 45mph. So this means the expansion would be the same. I would guarantee, that you would accelerate faster from 40-45mph with no spinning as you would going 0-5mph with the tires spinning. They would have same rotational speed and resultant forces, but the tires moving at the same speed as the road would be able to apply significantly more force to the road.
One observation from Canada.
A quote from the report says:
“On wet, snowy, or icy roads, where ABS is most likely to activate, the increase in fatal run-off-road crashes is a statistically significant 34 percent in passenger cars (confidence bounds: 20% to 50% increase). On these roads, all three types of fatal run-off-road crashes increase significantly for cars and so do fatal rollovers of LTVs.”
Which leads to the question: How many Americans use winter tires?
Every fall, up here in Canada, we are regularly bombarded with tv consumer ed features, news paper stories, pictures of car wrecks, etc., all aimed at getting out the message that:
(all-season tires) + ABS + (snow and ice)
= suicide pact.
The term “All-Season tire” is one of the most misleading concepts ever coined, by any industry. Most of these tires begin to lose measurable amounts of grip well above freezing temperatures (7 degrees C. about 44 F. believe it or not). At below freezing temperatures all- season tires are so inflexible you might as well have hockey pucks on your vehicle. Combine that with the on-off pulsing of an ABS system and you might have worse braking and steering than a non-ABS vehicle would provide.
fisher72>
I see this as well. For this reason, I always flicker my motorcycle lights (using front brake controls) BEFORE I intend to brake so hopefully whatever cell-yapping moron behind me notices the “blinking lights”.
jmo : Ever figure the reason you didn’t stop is because there wasn’t enough traction to stop you? If the brakes had locked you would have still slid down the driveway just with locked wheels.
jmo, you need to re-read my post more carefully. The car WAS able to stop when I defeated the ABS and locked up the wheels. It stopped almost immediatly. It also slowed down perfectly well in gear, when not using the brakes. (incidentally, I was running 4 brand new Blizzaks, not all season bananna peels )
It’s pretty well known that ABS does not do well on deep soft surfaces, such as unplowed snow. In these conditions the ABS detects slippage and releases the brakes, when what is really needed is locking up, and allowing the wheels to dig in deeper.
BTW, The video you attached was of an icy hard surface, not a soft deep surface. This is a completely different scenario.
rpn453, … exactly.
If I am braking hard on the highway at the beginning of a jam, I always use the European custom of switching on the Hazards, I have noticed that trucks do this as well. But I think its helpful, especially if I am in the left lane.