Weather in Qiaocheng District 15.

"Volkswagen CC is broken!" In recent days, almost all the circles of Volkswagen riders have been screened by this news. 12 13 At 0: 50 pm, a serious bicycle accident occurred at the intersection of Tongxiang Road and Du Yao Avenue in Qiaocheng District, Bozhou City, Anhui Province. During the high-speed driving of a Volkswagen CC sedan with five people on board, the vehicle drifted out of control and hit a roadside telephone pole, causing two people to die on the spot.

Video pictures spread wildly on major websites. While we feel sorry for the dead, countless people have also started a "new round" debate about whether German cars are safe. Because the Volkswagen CC involved was cut in two by a telephone pole, but the telephone pole did not move (maybe it was just painted).

At this speed, this impact

What bus should I change? Maybe the result is the same.

This made everyone lament the high quality of domestic telephone poles and began to question the "conscience" of the public. But when we look at this matter objectively, we can't deny that the most vulnerable part of the car has always been the side! From the video, we can clearly see that the instantaneous impact point is located near the B-pillar at the back door of CC.

What's in the car door? A thin outer plate+a thin inner plate+a W-shaped so-called "cross beam". This itself is not used to withstand high-speed impact! Even if it is a "body side collision experiment", the impactor is not a steel pipe. In fact, some experiments of high-speed side impact of steel pipes have been done abroad, and the results are all "cut into two sections". Do you know how abnormal the thickness of the steel pipe of the telephone pole is? )

There are many reasons for the accident.

Speeding, roads, and ... tires!

Therefore, if the same instant impact is replaced by other brands and models, it is estimated that the probability of the final result is the same. So I think it is more practical to discuss "how the accident happened" than to discuss the material and design of the car itself.

The first place where the accident happened was near the intersection of Wang Yao Road in Bozhou, Anhui. According to the local speed limit in Bozhou, the speed limit of this road should be 60km/h, and the vehicles involved in the video are much higher than the speed limit (what is the speed of 60km/h in the picture? Look at other videos at a glance! )

In addition to speeding, some "analysts" also made some analysis from the professional angle of "saving cars" after the road surface fluctuated and the direction was out of control. But I think in addition to these factors, the tires of vehicles may also be one of the culprits of this accident! Because if this car had winter tires, it might have escaped!

Below 7 degrees, the performance of summer tires began to weaken.

If it is lower than 5 degrees, the tire test should be stopped.

As a "watershed", when the temperature is higher than 7 degrees, the grip performance of ordinary summer tires will be within the "normal range", and once the temperature is lower than 7 degrees, the friction coefficient between summer tires and the ground will continue to decrease, and the grip performance will begin to show a weakening trend.

With the further decrease of temperature, when the temperature is lower than 5 degrees, the grip performance of tire in summer has obviously deviated from the theoretical value of design. Therefore, if we refer to the EU tire test standard R 1 17, it is not difficult to find that the temperature condition of dry pavement performance test is "the temperature shall not be lower than 5 degrees", otherwise the test will be inaccurate.

The temperature was MINUS 4 degrees on the night of the incident.

Original car summer tires+overspeed = slipping

According to the very strict standards of the tire industry, it is only when the temperature is below 7 degrees that winter tires are changed. As for the tires of ordinary civilian cars, due to practical economic problems, tires with lower temperatures are usually used in summer. But usually when the temperature is below 0 degrees, you must be very, very careful if you continue to use tires in summer! ! !

Especially the thin ice that may be encountered on the road below 0 degrees is almost a "summer tire killer". It will cause the vehicle to slip out of control instantly. When the temperature is below minus 5 degrees, or even below minus 7 degrees, the tire grip in summer will basically be "poor". It is irresponsible to use summer tires reluctantly at this time for your own safety.

And my colleague "Brother Tai" paid special attention to and investigated the weather forecast in Bozhou, Anhui Province, and found that the temperature in Bozhou was MINUS 4 degrees that night! It happened less than 1 in the morning, almost the coldest time of the day. As we know, the original tires matched when the car leaves the factory are all summer tires (without exception, including the original tires of Volkswagen CC).

The temperature is too low, so it is recommended to replace the winter tires.

Don't forget: light the direction and brake slowly!

Before, a cyclist in xiaodian district, Taiyuan said that he wanted to change 1 set of summer tires for his car in the near future, so I stopped him. What's the temperature in Taiyuan now? I wonder if it's like riding for a long time. This is Goodyear's tire, which focuses on long mileage and gives consideration to mute performance. It is mainly emphasized that the carcass structure has high strength and good durability. But it's a summer baby! Not winter tires!

I will think of this accident in Bozhou: a speeding Volkswagen CC, the driver is not skilled enough. Why doesn't the tire slip in summer? Of course, nine times out of ten accidents are fast, even if we use the right tires, it doesn't mean I can drive casually! The word "light the direction, brake to slow down and predict in advance" 12 is valid at any time!

This article comes from car home, the author of the car manufacturer, and does not represent car home's position.