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Although British winters are mild for most of the time, a cold snap always makes roads treacherous and catches many motorists by surprise. It is important that a driver knows how to cope in conditions of sleet, snow and ice, and that his car is in good shape and able to deal with the demands imposed on it. Learn with experience how to drive safely in ice and snow: some people are timid and abandon their cars before they need to, while others do not make proper allowances for the conditions and end up causing accidents.
Tyre grip is your first priority in winter, so make sure that all your tyres (including the spare) are in good condition and have plenty of tread.
The best policy for motorists who are unable to leave their cars in the garage when it snows is to carry a set of chains or straps which can be fitted to the ordinary tyres when the going gets tough. Modern grip improvers can be fitted far more quickly than old-fashioned chains, but practise their use at home before you have to do it in a blizzard.
All forms of grip improvers are designed to work when there is a layer of snow between the tyres and the road surface, so take them off as soon as you are on a clear road again. The raised sections which dig down into snow also prevent 1-1ae tyres from gripping well in normal conditions. You will ouickly wear out straps or chains on normal roads, and the car will be uncomfortable to ride in. A worn chain can be hazardous if it snaps, for a piece of flying metal could hurt a passer-by or damage your car's bodywork. If you feel that your driving needs make it worthwhile, a set of knobbly-treaded 'mud and snow' or `town and country' tyres might be the best answer; they deal with mud and fresh snow quite well, but remember that their grip in normal conditions is not so good.
A vital piece of winter equipment is a small shovel kept in the boot. Apart from clearing away snow, it could be useful for gathering roadside grit to spread under the driving wheels if you run out of grip on a hill. Another idea for getting moving again if the driving wheels spin uselessly on ice or snow is to carry a couple of sacks and some tough string to tie them to the doorhandles. You can put them under the wheels for grip, and once you are rolling keep pressing on until a level road is reached before stopping to retrieve your sacks; but make sure that you use enough string to allow the sacks to trail clear of the back wheels.
Visibility is important, so make sure that your windscreen wiper blades and washers are in good order. Add a `screen-wash' fluid to the water in your washer bottle to give a better cleaning solution which will not freeze, and ensure that all the car's lights are kept as clean as the windows. The heated rear window fitted to most cars is invaluable, so buy a demisting element from an accessory shop if your car does not have one. Keep an aerosol de-icer and a plastic scraper in the car to clear frost from all the windows; another piece of sacking is also useful to drape over the windscreen if you have to leave the car for a few hours in freezing temperatures.
So many modern cars have complex heating and ventilation systems that it is worth studying the manufacturer's handbook to learn how to make the most of the controls. It is easy to obtain lots of heat to keep you warm, but make sure that you know the best combination of settings to keep all the windows free of condensation.
On a cold or wet day you often see cars with some of the side windows misted up, which makes you wonder how a driver manages to see properly at junctions; even worse, a few drivers even make do with wiping a smeary gap so they can see through the windscreen. Unless your car's heating system is unable to work efficiently, perhaps because air inlets are blocked with autumn leaves, it should be able to keep condensation off all windows. Condensation accumulates more quickly if you have several passengers in the car, so it may occasionally be necessary to open the windows a little — just half an inch should do — to keep plenty of fresh air circulating. Remember that it is just as dangerous to allow the interior to get so stuffy that there is a possibility of the driver drifting off to sleep.
Driving in fog
The basic lighting needs for your car for night driving are covered in Chapter 12, but it is worth adding that auxiliary lighting is even more valuable in winter. Since modern cars generally have very good quartz—halogen headlights, the most useful additional lighting is a pair of fog lamps. Check with a dealer specialising in your make of car what the manufacturer recommends.
One very valuable option, high-intensity rear lighting for use in fog (sometimes a single lamp, sometimes a pair), is fitted to most cars these days, but if your car lacks these it would be a very good idea to invest in a pair. These lights penetrate much further through fog than ordinary rear lights, so they give following drivers earlier warning of your presence. Since so many cars now have these lights, it is worth pointing out that in heavy traffic in fog, especially on a busy motorway or dual carriageway, a car without them becomes harder to spot among all the bright red beacons.
A word of advice, however, because the use of these lights is greatly abused. Many drivers switch on their high-intensity rear lights long before they are necessary, perhaps in moderate rain or slight mist. Worse still, a few drivers are absent-minded enough to forget to switch them off again, sometimes for days. The dazzle these lamps cause when visibility remains reasonably good is very irritating and tiring for drivers behind. Furthermore, it is possible that a pair which suddenly appears in the distance can be mistaken for brake lights. In short, use them when visibility drops below 100 metres, and do not forget to switch them off again when the weather improves.
A few other points about looking after your car are worth mentioning before we turn to the techniques of driving on slippery roads. As winter approaches, you should make sure that your engine's cooling system is topped up with a water/anti-freeze mixture. A lock which has frozen up can be thawed with a key heated by a match. Salt is very good at thawing snow and ice on the road, but it can also attack your car's bodywork; hose down the underside regularly through the winter, and especially thoroughly when spring comes.
The golden rule when driving on a slippery road surface is to do everything as smoothly and gently as possible: this is good advice for driving in all conditions, but it becomes absolutely vital when there is snow or ice on the road. You must constantly be aware of the danger of skidding because the grip from your car's tyres is greatly reduced.
A skid is invariably provoked by harsh movement with the steering wheel or using the brake or accelerator pedals too insensitively. When the road is slippery you should make each steering movement extremely gently, especially on snow or ice, and apply the same light touch to the brake and accelerator pedals. Skids usually involve either the front or rear tyres losing their grip, but sometimes all four wheels can end up sliding. Whether the front or rear wheels cease to grip depends on a car's handling characteristics and how it is driven, but generally rear-wheel drive cars are more likely to slide at the rear and front-wheel drive cars are more likely to lose grip at the front. The most common reasons are cornering too fast, applying too much power and braking on a bend. The feeling of a car beginning to move sideways can be unnerving, but the worry of skidding is greatly reduced if you know what to do.
There are many theories about how to deal with a skid, but the only correct method is the one practised by experts such as traffic police and experienced racing drivers. First, do not panic and stand on the brakes in an attempt to stop the car, as this will send the car even further out of control; stay right away from the brake pedal.
A rear-wheel skid is most commonly caused by applying too much power when driving a rear-wheel drive car through a corner. If this happens, the correct procedure is to lift off the accelerator to remove the slide-provoking power from the wheels, and steer into the skid so that the front wheels remain pointing in the direction you wish to travel. On a right-hand bend with the tail of the car swinging out to the left, therefore, you have to steer to the left to keep the wheels pointing down the path of the road. This opposite-lock, as it is called, will pull the car back into line, but take care not to hold the opposite-lock for a moment longer than necessary as the tail will swing out the other way. Pay off the steering as the car corrects its course so that you are ready to resume steering round the bend again. If you are too slow to correct the steering, the tail can start to act like a pendulum, swinging first one way and then the other, forcing you to apply opposite-lock in the other direction.
You must also avoid over-correcting the steering, as this can also induce a pendulum effect. All of this requires skill and sensitivity, but attempting to control a skidding car is better than doing nothing at all. If left unchecked, the car will skid off the road completely, or, equally seriously, collide with another vehicle.
Front-wheel skids are more likely to occur in a front-wheel drive car as a result of applying too much power, steering too sharply or braking too heavily, but steering and braking mistakes can also cause a rear-wheel drive car to skid in this way. Front-wheel skids can be more difficult to deal with because the car simply ploughs on in a straight line when it should be turning or stopping.
If the cause is over-heavy braking which robs you of steering control, the answer is to release the brake pedal momentarily to allow the front wheels to turn again, and then re-apply the brakes more gently. The most effective way of stopping quickly is by using 'cadence' braking - the on-off braking technique outlined in Braking. If you have tried to put too much power through the front wheels, lifting off the accelerator will allow the front wheels to grip - and steer - again. If the front-wheel skid is provoked by turning the steering wheel too sharply, your corrective action must also be to the steering. Straighten the wheel towards the straight-ahead position until you feel the tyres regain their grip, then start steering again, more gently this time, in the required direction, using all your judgement to avoid provoking another skid.
While all this advice ought to enable you to deal with a skidding car, great presence of mind is necessary when you have to put it into practice. A skid can occur so quickly and unexpectedly that you are best equipped to react if your actions are almost instinctive. This skill comes to some drivers more naturally than others, but all benefit from practising it. Since there is no substitute for acquiring experience in controlling a skidding car, it is very worthwhile to refine these instinctive reactions by practising on a skid pan. With an expert instructor by your side, you can learn so much in an hour or two that you will be able to control your car with far greater competence and confidence. You will find out exactly how skids are provoked, what they feel like and how you should deal with them, to the extent that the experience gained could make all the difference on the public road. If you do not know where you can receive skid pan tuition in your area, ask your local authority road safety officer.
When driving on slippery roads you must constantly be aware of how little grip your tyres have. There is far more to driving safely than knowing how to control a skid, because you must never take your car so close to the limit that a skid is possible. You must use the brakes sensitively and in good time, applying the braking techniques for wet roads described in Braking even more rigorously when driving on ice and snow. You must allow considerably greater braking distance between you and the vehicle in front, because the space needed to pull up on ice could be 10 times that required on a dry road. It is all too easy to be lulled into a false sense of security if you reach a section of road which is free from ice and snow, only to find that round the next bend the surface is just as slippery as before. You may find yourself with 50 feet in which to pull up when you need 500. Remember that speed is relatively easy to build up, but hard to take off.
Wheelspin at standstill
Even the best tyres can lose their grip and start spinning when the surface is slippery, and this can happen just as easily in summer mud as winter snow. This happens partly because the treads become filled with ice (badly worn tyres will lose their grip more quickly) and partly because water, liquid or frozen, acts as a lubricant between road and rubber.
When you find it difficult to get your car moving, the answer is to supply just enough power to the wheels to get the car rolling without causing them to spin. You must use all the finesse and sensitivity you can summon, but not be so restrained with the accelerator that the engine will stall. It is a good idea to start in second gear (or the second 'hold' on an automatic) and release the clutch gently so that the power is delivered to the driven wheels with minimum force. Should the grip be lost and the wheels start to spin, resist any inclination to press the accelerator harder to try to force the car to move. This will only make the wheels spin more vigorously and dig themselves down into the snow, making the job of getting out even more difficult. Get it wrong and you could find your car totally immobilised with its driven wheels stuck in deep ruts, when more sensitivity in the first place could have got you rolling.
You may find that you can move a foot or two before wheelspin starts. The answer is to release the power when the driven wheels start to spin, let the car roll back, dig away any loose snow and try again. If necessary, do this repeatedly by rolling back to the beginning of your wheel ruts, taking care not to allow any wheelspin which will deepen them. With patience and care, you might be able gradually to win a 'runway' with enough length for you to build up speed and escape. All the time remember that trying to 'muscle' your way out by allowing the wheels to spin on snow will only worsen your predicament. Passengers can help by spreading grit, twigs, sacks, rags, an expendable blanket or even the car's footmats under the driving wheels to improve traction, but make sure that you are well in the clear before you stop to pick up your `tools' and passengers.
As well as using a higher gear to get you out of a tight spot, remember that the highest possible gear is always best whenever driving on ice or snow. This will prevent you from provoking a skid by feeding too much power to the driven wheels. You should try to use one higher ratio than normal, but do not let the engine labour unduly.
Reading the road
Whenever the temperature is close to freezing point, you must be prepared for slippery roads. It is vital to understand the conditions, and read the road so that you anticipate dangerous spots before they catch you out. For example, on a frosty night when major roads have been salted or gritted, do not expect minor roads to have been treated in the same way. Even on a fine day when the road surface seems normal, be aware that ice might have remained where trees and walls shade the road, or where wind sweeps across an exposed hilltop or bridge.
The notorious, and often misinterpreted, winter hazard of black ice should always be expected on a cold night, and for several hours in the morning after a cold night. Black ice occurs where water has melted during the day, spread across the road and then frozen again as the temperature drops after dusk, creating a surface like an ice rink. The danger is that you may think the surface of the road illuminated by your headlights appears to be wet, when in fact it is icy. Because it occurs in patches, it is very easy to be caught out after driving for several miles along a road which seems normal. Black ice can be very frightening and should be treated with the greatest respect.
Using your powers of observation can keep you clear of many of the problems which winter can throw at you, but just occasionally even the most sensible driver can find himself stuck fast along a quiet country road. Only you can decide whether to wait for help or to go looking for it, depending on how remote you are. This might never happen to you, but if it does you will be glad if you have been far-sighted enough to keep a shovel, wellington boots, gloves and plenty of warm clothing in your car. You can keep warm, of course, by leaving the engine running with the heater switched on, but do not make the potentially fatal mistake of leaving the engine running for too long. Exhaust gases contain poisonous carbon monoxide (with no taste or smell) which kills if you inhale enough of it. Many exhausts leak small quantities of gas which are blown away unnoticed when you are driving along, but which can seep into the passenger compartment when the car is stationary. If already tired occupants begin to doze off in the warmth, you can imagine the danger. If it really seems pointless to start walking in seek of help, rely on thick clothing as well as the car's heater to keep you warm inside, and get out periodically for a brisk walk to revive your circulation.
Make sure that your car is properly prepared for winter driving.
When roads are slippery, use all the controls steering, brakes, accelerator, clutch - even more smoothly and gently than normal to avoid the danger of skidding.
Be completely familiar with the procedures for controlling a skidding car: steer into the skid and do not brake. It is an excellent idea to take your car to a skid pan so that you learn exactly how to handle it.
If your car is stuck in snow, use second gear and a gentle throttle to avoid wheelspin.
Read the road to prepare yourself for slippery spots; treat the surface with the utmost respect if black ice seems a possibility.
Traducido por Juan Pita
Juan es una máquina de traducir. En todo momento parece estar estimulado por algún tipo de bebida que prepara en un recipiente portátil y que requiere de dos litros de agua hirviendo.
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