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View Full Version : Why do you turn in the direction of the skid?


Naga1337
04-02-2009, 12:32 AM
The only time I have ever gone into a real skid (on ice,) I simply turned the wheel just a little bit in the opposite direction and slammed on the gas (FWD) and I recovered from the skid. It seems that turning into the skid would make you spin out, and possibly go into the path of oncoming traffic. Actually, when I went into the aforementioned skid, if I turned into the direction of it, that is just what would've happened. Can someone explain to me why you are supposed to turn into a skid? Thanks.

Professor_Skullsworth
04-02-2009, 01:16 AM
so the tires regain grip. It is the same reason why you have to paddle a boat down a fast moving river,...okay that doesnt really help unless you are in my head. Wait until Nereth explains it with numbers and shit im tired,...

driveby
04-02-2009, 01:21 AM
Because then the asphault will spin the wheels, and you will re-gain control of the fucking car.

LOL, I skidded like 4 times, one time, I spun out.

ratfrink
04-02-2009, 10:01 AM
Steering into the skid is what your dad tells you to do, I'm not sure if it's right in every situation though. I suppose it depends if your car is RWD or FWD and whether it's the back or the front that's spinning.

If a RWD car is tailing out then coming off the gas and steering in the opposite direction seems to help (own experience, wet roundabout)

I've never been in a four-wheel drift so I don't know about that one. And I've never had the rear wheels skidding in a FWD car (except by pulling on the handbrake in icy car parks/fields (almost got banned from Henley Royal Regatta by doing that; Camping fees 50, countless bottles of Pimms and lemonade 200, drifting in a 30 year old Datsun with a checkered bonnet blaring out Prodigy wearing a cream jacket, stolen silk tie and a boater hat in probably the poshest place I've ever been to - priceless).

Nereth
04-02-2009, 11:30 AM
I'm gonna try to make this fast as I'm busy, let me know if something needs to be clarified (and I imagine something will).

Almost invariably, you get into a skid while trying to turn a corner that is too sharp for your speed and car. When you start skidding, you'll notice your turn widens out... becomes less sharp, and you start heading for whatever obstacle is on the outside edge of that corner, be it tree, signpost, or concrete divider.

Your goal then, to get through the skid without a spot of death, is to apply more force (known as "lateral force") on your car in a direction away from that obstacle (read, apply force towards the inside of the turn).

It is the job of your tyres to do this.

Background: There are two very important directions in a tyre supplying lateral force. One is the direction the tyre is pointed (Which I will call the "heading"), the other is direction the tyre is actually moving over the pavement (which I will call the "course"). If you are traveling in a straight line these are more or less the same. In a turn however, these two directions do not line up. The tyre actually scrapes sideways across the ground somewhat (it scrapes towards the outside of the turn) so that an angle develops between the direction of the tyres motion and the direction the tyre is facing.

This angle is known as the "slip angle" and is one of the most important parameters in vehicle dynamics. The higher the slip angle, the higher the force generated towards the inside of the turn. To a point.

http://features.evolutionm.net/imageview.php?image=1538

That is a graph of force generated versus slip angle. As you can see, up to about 6-7 degrees, more slip angle=more force, which is nice, the whole system seeks it's own equilibrium in a way that I would like to call 'beautiful' but that would make me a geek so let's just call it 'interesting'.

However, as you can see, past 6-7 degrees (the exact value depends on a lot of factors), you can see that the force starts dropping down again (unfortunately that graph ends shortly thereafter). And the problem is, once that force starts dropping, the equilibrium I mentioned earlier goes straight out the window, and the system is fundamentally unstable. The more it drops, the faster the slip angle increases, the faster it drops, etc.

A skid is what happens the moment your slip angle increases beyond that threshold. Suddenly you have damn near no favorable force from the tyre (the force you do still have acts to slow the car down mainly, not turn it).

So to solve this problem, all you have to do is decrease the slip angle. That means, make the heading (direction tyre is pointing) line up more with the course (direction tyre is going). In a skid, the course is going to be well and truly towards the outside of the turn as that is the direction the tyre skids, and thus you want to turn your heading out to match it, i.e. turn the tyres towards the outside of the turn. This decreases the slip angle and restores you to the peak (or the safe side of the peak) of that graph.

Which isn't to say that being on the peak will automatically save your life. It *still* may not be enough, but it's more than you have when you are over the peak. Make sure not to overcorrect and actually get a slip angle towards the outside of the turn though :D

CitizenUzi
04-02-2009, 03:46 PM
Complicated explanations aside, everyone NEEDS to experiment with skids in a parking lot or something under all conditions and preferably in various different cars. I can't explain it like nereth can, but after 6 years of fucking around in everything from 2 ton RWD monsters to civics, I trust myself to react correctly. I haven't fucked up a skid-correction or drift (accidental or otherwise) since 3+ years ago when I was practicing in an RX7 in 1 foot of snow. The key things here are PRACTICE and experience!

Rocko
04-02-2009, 05:20 PM
Parking lots? Fuck that. I learned how to control a skid when I threw my mom's FWD Matrix around a 90 degree gravel-covered turn at 45 mph. Yes, FWD cars CAN skid.

And that's why my parents don't let me borrow their cars anymore. :D

Alamo
04-02-2009, 06:36 PM
I typed out my own version but was just confusing unless you were me so lol found this and this is a pretty good breakdown of scenarios ect...


What's the best way not to get into a skid? Avoid it in the first place! One of the best ways to avoid trouble on the road (not just skids) is to drive smoothly. True professionals drive so seamlessly that you do not feel anything when they shift, turn, or brake. Plan ahead, watch carefully, and slow down, especially if you are unfamiliar with the road. Skids almost always happen because the vehicle was running too fast for conditions.

Know How to Recover from a Skid Be careful when conditions might be slippery, as this is when most skids occur. But no matter what the road's surface condition is, skids are caused by driver error. Try to turn too sharply, enter a turn too quickly, or use excessive acceleration or braking, and you'll get the chance to practice skids! Keep your brakes maintained and properly adjusted, because a lateral imbalance in your brakes can cause or aggravate a skid.

There are two common types of skids. "Oversteer" (or fishtailing) occurs when your front wheels are taking a shorter path than desired and the rear-end breaks loose and fishtails. This is the result of power and side forces causing loss of traction on the rear wheels; there is too much power applied for the existing steering input and the resulting side forces cause the rear wheels to break free, often as a result of trying to accelerate out of a turn. "Understeer" (or plowing) occurs when you have too much steering input for the power you are applying (too sharp an angle between the tires and the direction of motion), and the front wheels skid ahead as a result.

Professional driving instructors advise a new way of teaching skid recovery, instead of the old rule, which was, "Turn into the skid." They say this "new" way is more understandable to non-professionals, but either way, they adamantly say the result is the same. This change was made because many folks didn't clearly understand what "turn into the skid" means.

If you find yourself in an over-steer skid, first thing to do is get off the gas, keep your foot off the brakes, or smoothly release brake pressure if already applied, and if you are driving a standard shift vehicle, disengage the clutch. Quickly turn the steering wheel in the direction you want the front of the car to go (down the road). Specifically, this means align your tires with the direction of your intended travel. As your vehicle turns back in the correct direction, you must then counter steer in time to stop the turning and stay on your desired path. If you do not do this promptly, the vehicle will continue to turn past your intended direction, and you may then skid in that direction. You may have to counter-steer more than once to get things under control.

[Editor's Note: There are two situations where the previous techniques could actually make the skid recovery more difficult. When you are driving either a front-wheel drive vehicle or a rear-wheel drive with the four-wheel drive engaged, a quick reduction on the accelerator can cause a result in a loss of control that mimics what happens when the brake pedal is depressed -- namely, the front wheels are slowed faster than the rear wheels increasing the over-steer skid problem. What is generally recommended is to place the vehicle into neutral (or depress the clutch) to allow the front wheels to coast as the vehicle is turned in the direction described above. My own experience is that control is much easier to reacquire by applying a steady pressure on the gas pedal as one "drives" out of the skid, but this assumes that the driver was traveling an appropriately slow speed to begin with. Our thanks to reader L.N. from York, PA, for reminding us of this issue.]

For an under-steer skid, slightly reduce your steering input while slowing (without heavy braking) so you'll regain your directional control as the tires again grip the road surface. In this skid, the critical issue is to reduce speed so that you can regain a grip on the road and complete your turn. Even just a slight decrease in steering input, combined with the reduction in speed, may be enough to stop the skid from progressing.

These techniques are something you need to practice. If there are any high performance driving schools in your area, take advantage of the "safety" course they offer and you'll get the opportunity to practice skid recovery under safe, controlled conditions. You'll have a better idea of what to do, and a better idea of your own capabilities behind the wheel. I guarantee you will be a safer driver.

Township Rebellion
04-02-2009, 09:12 PM
I thought the OP basically had it right for his situation. If you're rounding a right-hand corner and the rear end steps out and suddenly you're sliding sideways pointing to the inside of the corner, you don't want to continue steering right. To me, that seems counter-intuitive. Apply some opposite lock (turn wheel to the left; as Nereth explains, point the front tires towards the direction you are actually moving, or at least where you ought to be moving), then once the rear end comes back into line, makes sure you've turned the steering wheel back to the right so the fronts follow the correct path, pulling the rear back into line. If you give too much opposite lock in the first place, you'll over-correct and instead of your ass pulling in line it'll swing out in the opposite direction. Then you'll REALLY be fucked. If you don't apply any opposite lock and continue to simply steer right, you'll fly ass-backwards into the ditch on the outside of the turn.

I don't understand why anyone has to make such an overly complex explanation of something so simple.

Rocko
04-02-2009, 09:28 PM
The overall goal of oversteer control is to keep the front wheels pointing the direction you want to move. You steer opposite the turn because the car is rotating and making the tires point to the inside of the turn.

IMO, that's not as hard as knowing when to straiten it out again to avoid spinning the car around when the tires suddenly decide to grip.

driveby
04-02-2009, 11:31 PM
I skidded on the US 60 freeway, a state divided highway, and spun out on a dirt road curve, hitting it at 40.

Alamo
04-02-2009, 11:51 PM
I skidded on the US 60 freeway, a state divided highway, and spun out on a dirt road curve, hitting it at 40.

:facepalm: Lol I hope it wasn't that car with the bad brakes.

Township Rebellion
04-03-2009, 09:31 AM
Before I go to bed, boys; had a wild drive home tonight. I'm in whistler, and we went into town for a schmoke. The drive back proved to be tricky due to sudden, very heavy, fluffy, wet snow. Wound up overshooting my turn off by like 10 clicks. At one point there was a downhill section heading into a right hander. At a bit under 60 Ks I braked and the van immediately slewed sideways to the left. I wound up feeling the front wheels and the brakes and brought the fucking thing back into line. Thank fuck for instincts.

And all this while an incessant, drunk aussie is badgering me. I'm wrecked, but we made it... barely. No gas left either :D

ratfrink
04-03-2009, 09:48 AM
I've been to Whistler!

I remember a little sandwich shop called Moguls, it was right next to the hotel. And the Mongoli Grill restaurant where they cook the food in front of you.