Winter Driving
I originally posted this over on Song of the Paddle but thought it might be of interest here too....
I have been reading the various threads dotted about the internet and thought it might be useful to a few members if I jotted down a few pointers.
When not running Bushcraft Courses I can be found teaching Skid Avoidance and control techniques.
There are generally two types of Skid.
The front wheel and the rear wheel skid. The classic under steer and over steer for those that watch Top Gear.
Most cars on the road these days are front wheel drive about 80%. Been a a while since I checked the data.
The means 20% are rear wheel drive or 4 wheel drives.
You can achieve a front wheel skid in a rear wheel drive and rear wheel drive car.
The bad news is your more likely to get a front wheel skid in a front wheel drive car.
80% of all skids are caused by excessive speed for the road conditions. Common sense tells you when its slippery to slow down.
15% of skids are caused by harsh breaking. If you treat your car nicely it will be nice to you.
That leaves only 5% for breaking. Excessive braking is actually a factor of too much speed.
So what should we consider to reduce our chances of having a uncontrolled skid?
Our tyres are important. The provide grip and directional control. The legal limit for tyre tread in the UK is 1.6mm. However we recommend you change your tyres at 3mm. At 1.6 your working at around 10% of the tyres efficiency.
Next question is how often to do check your tyre pressures? An under inflated tyre can cost you 3 points and a fixed penalty. Also you will not be getting a proper grip with the road surface. Less grip more chance of a skid.
I recommend people check their tyre pressures weekly when the car is cold. Once you have driven a few miles the pressure in the tyres will increase and you will not get a true reading.
Also when checking run your hands around in the inside checking for bulges chips and splits. A blow out at 70mph is seriously going to spoil your day.
The rear wheel skid.
You are entering a right hand bend to quickly for the road conditions and the weight will transfer to the nearside front wheel. This will cause the back to lose grip and start to slide.
What do you do?
Firstly the cause of the skid was too much speed. Therefore I need to slow down.
DO NOT Brake.
Take you foot off the gas. FOG.
Now its time to steer in the direction of a the skid.
This means if the back slips left your turn the steering wheel to the left. If you steer to the right you will do a graceful 360 and hit the car that was following head on.
Your now travelling sideways so reset the steering and relax allow the car to become balanced count 1 2 3 and Gently reapply the gas.
If you hit the accelerator too soon you will start to fish tail and eventually lose control.
Why do not brake?
Breaking in a skid situation will cause the wheels to stop rotating so you will lose all traction with the road surface and therefore will actually increase speed briefly. To steer you need wheel rotation. So by breaking you will hit the Oak faster and in a lovely straight line.
The good news is that rear will skids (over steer) are very tactile and instinctive to control.
The front wheel skid.
This skid is the one that catches most drivers out. When driving in country lanes we have all sadly seen the bunches of flowers by the roadside. These are generally located at the exit of the bend. It was the front wheel skid that got them (under steer).
The front wheel skid is NOT tactile so therefore is it difficult to detect. One method I teach is to look at your limit point. That is to look as far around a bend as you can safely see. We could all do with increasing our focal point when driving.
It is just like going for an eddy. Cars and canoes go where we look.
So now we our entering this right hand bend a little too fast for the conditions. We set our steering and start to turn but something is not quite right so we set more steering to force the car around the bend. The car is no edging closer to the ditch.
You have set enough steering to end up in your neighbours kitchen but you are heading towards a tree. something must be happening to the car. That is a loss of traction through the front wheels.
Action:
DO NOT BRAKE.
Take you foot off the gas. FOG.
Keep looking in the direction you want to go and gently rock the steering wheel a quarter turn slowly and deliberately. This improves the surface area in contact with the road surface and will help you regain control sooner.
Once the car is balanced again count 1 2 3 and gently reapply to gas. This time if you apply the gas too soon you take weight off the front wheels. It was the front end causing the problems and you will go into a secondary front wheel skid. Do you have room for 2?
If necessary drive to a safe spot and stop. Relax and phone a friend. Do not stop immediately after you skid. The driver following may not be as competent as you and will park in the rear of your car.
Do not try and power your way out of trouble. Drifting properly takes lots of practice a good road surface and decent tyres. It your skidding in an emergency the you will just increase your turning circle but apply power too early.
Do not try and change gear. You want maximum engine braking to slow the car down to regain grip as early as possible.
Automatics are much harder to control in a skid. No engine breaking. The two techniques above still work it just takes longer.
4x4's are not get out of jail free choices. Plenty of off roaders will have slide down a wet grassy slope. A four wheel drive car generally allows you to push it closer to its limits of traction before it lets go. You are therefore likely to travelling slightly quicker and instead of losing grip at one end you will be travelling sides with no traction on any wheels.
Same rules apply do not brake. FOG. Most often with a landy the rear will slide before the front so teat the slide as either a rear wheel if the back went first or a front wheel if the front goes first.
Sorry for the long post but I thought it might prove helpful to some.
Reply With Quote
Originally Posted by Dogoak
and didn't wreck mine.
.
(IMO too fast). Those were the ones I had to collect from the street, while driving an ambulance during my civil service and then they still asked why we drive that slow! 
.
