ditto to all that... Living in Canada I have similar experience (though not so much with 'sand' more snow) .... and since snow is coming, it is time to change mindset while driving. I can say with some certainty that, in all situations (except snow and other loose surfaces), ABS is better than nothing. It is 'known' that in snow, if you skid, the snow builds up a 'bow wave' in front of the wheel, and helps the vehicle stop, but, with ABS, the vehicle's wheels will unlock, causing the wheel to roll over the snow, and take longer to stop. Like Forrest says though, what you lose in stopping distance you more than gain in control. On the other hand, technically, in more normal situations and on more normal surfaces (including ice), an exceptional driver will be able to beat ABS in stopping distance always... in other words, a driver who is able to apply the brakes with just the right pressure to keep the wheels rolling while still braking to the 'max' will have the best stopping distance, and still maintain control... in other words, a skilled driver will be able to outperform ABS in stopping distance and control. Wile this may be true, the fact is that there are two issues that people seldom take in to account.... 1. even skilled drivers make mistakes, and there are pathetically few drivers who have the skill in the first place. I would venture that none of us on this list are skilled enough to perform such precision driving all the time... 2. Even with ABS, the ABS only engages when the driver locks a wheel, so, there is no downside for a skilled driver to have ABS because they will 'never' need it. In other words, if you are such a good driver that you can out-perform ABS, then you should have never experienced the effects of ABS..... in the corollary... If you have ever experienced the shudder of ABS, then you are not skilled enough to outperform it.... oddly, F1 banned the use of ABS on the F1 vehicles because it gave the drivers too much advantage, causing them to brake later in to corners, etc. If ABS enhances the abilities of the most skilled drivers in the world, who earn millions by driving on the edge... then I would be a fool to say that I can do better. Rolf On Mon, 23 Nov 2009 05:56:44 -0700, Forrest Christian wrote: > Having lived for the past 15+ years in a state (Montana) where adverse > driving conditions are a way of life for a large chunk of the year, I > can say that I'm definitely familar with ABS vs non ABS. > > With a few exceptions, driving in snow/ice (and I guess normal driving > as well) is all about retaining "adhesion" to the road surface. By > adhesion I mean that the tire treads and the road surface are moving > together (or I guess opposite to each other). Any skid/slide in any > direction means you are unadhered to the road. I should also mention > that I do use some words like stuck in their 'adhesive' meaning below - > so be aware. > > The reason why remaining adhered to the road is important is that > without that adhesion, you have no control of the vehicle. It goes > where it wants to, no matter where you turn the wheels. it should also > be noted that once adhesion is lost, it is quite hard to get it back. > All of the rules such as "turn your wheel into the skid" and similar are > all about trying to get the wheels re-adhered to the road. > > So, we're talking about braking here. In a Non-ABS vehicle, if you hit > your brakes really hard (or even barely in some conditions), the tires > lock up, and become unstuck from the road. As a result, you loose > steering, and all control. It is really easy to get into a skid in an > non-abs vehicle. Just hit the brakes on packed snow and ice. Your > wheels will lock up, even briefly, and you'll end up in a ditch. A > good driver can and will get used to how much pressure and/or in what > manner to apply it and will actually simulate the action of an ABS system. > > With ABS, it's harder to loose adhesion. Yes, sometimes conditions are > bad enough that even a slight tap will do it, and abs isn't fast enough > on some vehicles to handle it. But for the most part, braking an ABS > vehicle will always help. Yes, you can come unstuck doing things which > involve lateral motion - yanking the wheel, or going around a corner too > fast for conditions. But when it's braking which is involved, becoming > unadhered is a lot less of a concern. > > About the only place where ABS hurts is where you are trying to stop in > the shortest amount of distance. I'm not sure about dry-pavement, but > I know that in sand and snow and other situations where a locked tire > will tend to 'dig in', abs significantly increases stopping distances. > This of course has to be balanced with retaining the ability to actually > steer. In an ABS vehicle one should apply firm pressure and do what > they can to steer around the obstacle. Contrast that with a non-abs > system where one can either jam on the brakes, and hope they skid to a > stop before the obstacle, or try to apply appropriate pressure to the > brakes so that they can still steer around it. > > Personally, I'm much more comfortable in an ABS-equipped vehicle. It > allows me to do less thinking in an emergency situation - in all > situatitons the correct answer is hit the brakes and look for an escape > path to drive around the problem area. > > -forrest > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist