Five silly winter driving questions
Things you might be too shy to ask about driving in ice and snow.
Severe winter weather is well and truly with us in many parts of New Zealand. Kind of happened all of a sudden, right?
When the roads are covered in white stuff, you soon realise that you don’t feel quite as prepared for safe and stress-free A-to-B travel as you’d like to be.
Here are five silly questions about staying safe and in wintry driving conditions.
Being told to carry chains is all very well, but when do you put them on?
adventure. For four-wheel drive vehicles: you probably won’t need them at all unless things are dire. Tyres may also be a factor here. But if you have a vehicle with an ‘‘on-demand’’ 4WD system (where the rear wheels are only driven when the front ones start to spin), it’s not a bad idea. Again, pays to do some homework on how your vehicle operates.
When the glass fogs up, is it OK to clean it with your hands?
driving where you’re speeding up and slowing down all the time (intersections for example), and on the open road, where you have to keep V-max to a very cautious level.
Problem is, braking requires grip and you don’t have much when there’s snow and ice about. Anti-lock braking systems don’t always inspire confidence in an emergency, either: it’s technology that actually depends on friction between tyres and tarmac to work (the wheels ‘‘lock’’ and release many times per second).
Naturally you should keep a smooth and slow(er) driving style in slippery conditions, but using engine braking to control your speed or slow down can give you much more control and confidence.
Engine braking is something we all used to know about when manual-transmission cars were a thing: by selecting a lower gear than required for the road speed, the compression/friction from the car’s engine slows the vehicle with minimal use of the brake. So there’s much less chance of skidding and a smoother transition to a lower speed.
Even at a constant speed around ice and snow, going a gear lower than you normally would can help keep the car stable, because the slightly higher engine speed means you’re controlling the car on the throttle more than the brakes.
And yes, you can still engine brake with an automatic. Most two-pedal cars give the driver the ability to select and hold a particular gear.
Do the standard rules about following distances apply in slippery conditions?
We all know the two-second rule, right? Calculate your following distance by counting ‘‘one thousand and one, one thousand and two’’ as the car in front passes a stationary object. If you pass that same object before you’ve finished counting, you’re too close.
The beauty of the two-second rule is that it’s a time rather than distance thing, so it works equally well at any speed.
But it doesn’t work when there’s ice and/or snow in the mix, because your car takes so much longer to respond to steering and braking inputs. The general rule for driving in slippery or lowvisibility conditions is at least four seconds between vehicles, more if conditions are particularly bad.
Leaving a longer gap not only gives you time to react in an emergency, it also allows you more opportunity to see what’s happening ahead. If the car in front is struggling to stop at an intersection, for example, then it’s going to be the same for you. You’ll have time to prepare.
Black ice... what exactly is it again?
Ice is usually white. ‘‘Black ice’’ is completely transparent, which doesn’t seem to make much sense. Although it does sound ominous, which is appropriate.
Black ice is thin enough to be invisible on tarmac, which is... black. See what they did there?
When ice or snow melt and the ground doesn’t dry completely during the day, the water can refreeze and create black ice. It can also form from dew or fog.
Black ice is extremely dangerous because you can’t see it’s there. It’s most common in shady spots that don’t get sunlight during the day.
But also be wary of bridges, because cold air can flow underneath and prevent a proper thaw. What should you do if you hit black ice and lose control? It can be very frightening, but try not to panic.
Stop accelerating, don’t brake – and odd as it may sound, don’t turn the steering wheel, because you don’t have control anyway and it’s crucial to know which way the wheels are pointing when you regain grip.