Imagine how desperate you would have been if, on a steep downhill section, with sharp bends, you suddenly noticed that the brakes were failing? In the past 10 years, at least a thousand drivers on a single road have experienced such desperate moments. This road is the famous "Slope of Death" Kunmo Expressway Gale Pass 27 kilometers long downhill.
If this road is really realistic to drive over, you know how dangerous it is, although it is high-speed, but the trucks are all speed limit 40, cars are also limited to 60, the country has never seen such a low speed limit of high speed bar, that is because this road is really very dangerous, the length of 27 kilometers, but the drop is more than 1100 meters, winding and built, not all slopes are steep, but the slope length, bend, more tunnels, but also easy to fog, it leads to the road danger is very high, since the opening in 2004, In just 10 years, at least 1,100 trucks have lost control, 124 people have died, and 300 trucks have spontaneously combusted, and the number alone is shocking.
Why is the long downhill section so dangerous?
Some people say that the downhill section is not just a slower drive? It's not as scary as you say, then you haven't been to the Yunnan-Guizhou Plateau. Go out and see the world. The downhill section is not terrible, the terrible thing is that the downhill road is long, the slope is large, and there are sharp bends, and these three conditions are very terrible when combined.
The reason why there are so many accidents in the long downhill section, in addition to the speed of the car, most of them are caused by the thermal attenuation of the brakes. Brake thermal attenuation, as the name suggests, is that frequent braking causes the internal temperature of the brake to be too high, resulting in an extended braking distance, and even the brake failure, which is very dangerous.
Many people mention the brake heat attenuation that only the big car will exist, the car does not have to worry about the brake heat attenuation, in fact, it is not, the brake heat attenuation whether it is a large car or a small car exists, just because the big car generally uses a drum brake, and the car is heavier, it is easier to brake.
However, ordinary family cars, after frequent braking or multiple rebrands, will also appear thermal attenuation, resulting in an extended braking distance, but there is rarely a brake failure. Looking at the eighth time of the Ford Wing Bo test, the braking distance was extended by 6 meters, and in some emergencies, this 6 meters may be the distance between life and death. Therefore, even if the family car encounters a downward acceleration bend, it must brake in advance and leave a sufficient safe distance, otherwise it is very easy to cause the vehicle to lose control and overturn the suspension.
How to prevent thermal attenuation of brakes?
Experienced car drivers, when encountering long downhill sections, know that at this time must be hung in the low speed gear, as much as possible to use the engine's anti-drag braking, so as to minimize the use of brakes, safer and smoother downhill.
What about ordinary family cars? What to do when encountering such a section of the road?
First of all, manual transmission models and new energy models, do not panic when encountering long downhills, at this time you will be glad that you bought the right car. The manual transmission model is very simple, hanging low speed gear can be, similar to the principle of large cars. The new energy vehicle can even be charged for free when encountering a long slope, and the kinetic energy recovery can be placed in a stronger gear, and it can be charged while smoothly going downhill.
What about automatic models? Automatic models are more complicated, let's say the following:
1. Can I use a steep slope to slow down?
Steep slope slow descent is only suitable for very steep slopes, the general speed will not exceed 5 kilometers per hour, in this long downhill section, the slope is not as large as the basement, not suitable for steep slope slow descent, 27 kilometers of long downhill, you need more than 5 hours, down to dark ah, the back of the car can not stop and easy to rear-end you.
2. Hang S gear, L gear and M gear
Usually the owner of the car feels that the chicken rib of the S gear, L gear and M gear, when the long downhill section, can come in handy, you know, the car company engineer designed these modes are not used to watch, there must be its use of the scene, these gears have a feature, that is, can manually control the gear, when going down the long slope, hanging in the low gear can control the speed, this time the speed will be slightly higher, but it does not matter, control in the low gear, down the long slope when the speed is more stable, It won't make you feel like a roller coaster, and it's also a good way to avoid thermal attenuation of the brakes.
3, only the case of D block
Then you can only slow down the speed as much as possible, reduce the frequency of braking, and when necessary, stop in a safe area to cool the brakes.
Of course, there must be some people who insist that the car downhill is fine, there is no need to worry about thermal attenuation, the car's disc brake is indeed not obvious, but what we are talking about here is just in case, hanging to the S/M/L gear is also a second of time, there is no loss to you, but it can reduce a lot of risk for you, why not do it? Even if the probability of brake failure is only one in ten thousand, once it is encountered, it is 100% for you.