Which acceleration rate of a car can be critical for health?

Vadim Kulibaba
  • Which acceleration rate of a car can be critical for health?

2g or 5g? No, this is not speed of the Internet. This is accelerating force when the a car gains its speed from rest. And what is critical load?

One of the main parameters of a car is acceleration rate, from zero to a hundred. All companies are trying to make this time interval as short as possible. But can the start be so fast that it will be harmful to human health? Is it far from the limit of the possibilities of the body?

Acceleration is a physical value that determines the change in speed over time. This parameter is measured relative to the surface gravity, or relative to the gravitation acceleration, which are essentially the same. Acceleration is indicated by the letter "g" and is equal to 9.8 m/s². 1g is equivalent to the force of gravity.

Acceleration in a car

With increasing speed, a person is subject to G-force aligned with horizontal x axis. To achieve acceleration rate which is equal to the gravity force, the driver must accelerate from zero to the first 100 kilometers per hour in 2.8 seconds. While average cars achieve 100 km/h speed only in 10 seconds, and g equals 0.28.


But there are cars that are accelerating no worse than rockets. They are called dragsters. These are the cars with engines that produce from 7,000 to 10,000 hp. Dragsters with these capacities can achieve 100km/h speed from standstill in 0.5 seconds. With such indicators, the acceleration is 5.6 g, and affects the body, but is not critical.

The effect of a force of 6g is considered to be critical for a non-trained person. With such a load without preliminary training, you can lose consciousness, or even die. There are cases when people survived even when they were subjected to forces of 100 g, and this is only due to the minimum short period of time of the impact force.


World record

Pilots of military aircraft in special suits sustain an overload of 9 g, but the world record of the experienced impact acceleration belongs to the US Air Force officer John Stapp. John withstood impressive accelerations of 46.2 g, piloting a rocket sled at the Edwards Air Force in California. But an ordinary person without training could not withstand such acceleration.

Even Stapp himself performing tests on the sled had several unsuccessful races, and was injured. During one of which at an acceleration of 35 g, John lost several fillings from his teeth, cracked his ribs, and had experienced some delicate problems.

Therefore, the limit is set at 30 g, with the minimum number of injuries. This means that the acceleration from zero to one hundred should take still incredible 0.093 seconds. And with a record acceleration, which John Stapp withstood, the speed of 100 km/h was achieved in 0.06 seconds.

So the automobile manufacturers still have room for improvement of the results of acceleration rates of their vehicles without jeopardizing drivers’ health.