As the saying goes, it is easy to go downhill and difficult to go downhill, in fact, not only for people, but also for vehicles, driving uphill is nothing more than increasing the throttle to hang low-speed gears, but once the downhill speed is not well controlled, it is the result of car destruction and death.
Why is the "Highway of Death" so dangerous?
The Ministry of Public Security announced the country's top ten accidents and long downhill sections, of which the Song waiting line provincial highway in Kunming City is 77 kilometers plus 800 meters to 66 kilometers plus 400 meters, causing the largest number of accident deaths since its opening. In the 10 years from its opening in 2003 to 2013, there were 218 road traffic accidents on the 11.4-kilometer downhill slope, resulting in 279 deaths.
Why is the long downhill section so dangerous? Because these sections are all long downhill sections with large slopes and long distances, these sections are the most prone to brake heat attenuation.
The so-called brake heat attenuation, that is, the brake system after a long time of work, because the heat accumulation is too much, resulting in the braking distance is extended or even the brake failure phenomenon, and the long downhill section because of gravity, even if the accelerator is not stepped on the accelerator, the vehicle will continue to accelerate, so the driver needs to constantly step on the brake to control the speed, because it is very easy to produce brake heat attenuation. Once in the event of rain and snow, the road surface is slippery or icy, and it is more likely to be dangerous.
How to safely go downhill for long periods?
Brake thermal attenuation, generally speaking, often occurs in trucks and other heavy weight, and most of them are models that use drum brakes, which are not as good as disc brakes in terms of heat dissipation, so brake thermal attenuation is more likely to occur. So for this long downhill section, how to operate is the safest?
Manual transmission models
Experienced big car drivers know that in the long downhill section must hang low speed gear downhill, this is because in the case of low speed gear, you can use the engine's anti-drag to control the speed, the principle of this is to rely on the inertia of the vehicle to drive kinetic energy, part of which is converted into the kinetic energy of the engine compressor work, in the case of not stepping on the throttle, most of the kinetic energy in the engine intake and exhaust process loss, so it can play a role in reducing the speed, the lower the gear, the more obvious the effect. In this way, the frequency of use of the brake system is greatly reduced, which greatly reduces the probability of thermal attenuation of the brake.
Automatic models
Generally speaking, domestic cars are manual transmissions, very few automatic transmissions, and for general family cars, the basic use of disc brakes, brake heat attenuation problems rarely appear. However, rarely appear does not mean that it will not appear, even if there will be no brake failure, the extension of the braking distance will also appear, in addition, the use of engine braking can help us safer and smoother downhill, the passengers in the car feel better, so how to operate?
First check your own automatic gear model, there is no S gear \ M gear \ L gear, these gears can be manually controlled in the low speed gear, using the engine to brake. Take the S gear as an example, the gear is hung into the S gear, at this time as long as the engine speed does not reach the red line area will not be upgraded, and then through the gear shift paddle or the gearbox's plus or minus gear button, hang into the low gear.
If the above gears are not available, it is recommended that if you encounter such a long downhill section of the Yunnan-Guizhou Plateau, try to use uniform braking force to control the speed within a reasonable range, and in the case of necessity and safety, stop and rest in the lane specially set up on the side of the road, let the brake system dissipate heat, and ensure that nothing is lost.
Long downhill sections, absolutely can not be taken lightly, countless bloody accidents tell us how terrible the brake heat attenuation is, clever use of engine braking, is the best way to brake when going downhill.