A NASCAR racing car is basically a skeleton of strong metal tubing covered with thin, metal sheeting. The cars are equipped with a variety of safety devices that have evolved over the years in response to accidents and crashes that have injured or killed drivers. Let's start with how the car protects the driver.
The Roll Cage
The key to surviving a crash is for the car to remove the energy from the driver's body as slowly as possible. Street cars have many safety devices designed with this in mind. The structure of a street car is designed to crush and thus absorb a lot of energy, giving the other safety devices, like seat belts and airbags, more time to slow the driver's body down.
A NASCAR race car uses some of the same techniques. There are three parts to the frame:
- Front clip
- Rear clip
- Middle section (including the roll cage)
The front and rear clip are built from thinner steel tubing so that they will crush when the car hits another car or a wall. The middle section is designed to be strong enough to maintain its integrity during a crash, thereby protecting the driver.
In addition to being collapsible, the front clip is designed to push the engine out of the bottom of the car -- rather than into the driver's compartment -- during an accident.
The seat has several important jobs:
- It must keep the driver inside the roll cage of his car.
- It must keep the driver from contacting anything hard during a crash.
- It must absorb some of the energy of the crash by bending.
In the past, several deaths occurred when drivers still in their seats were thrown from cars. To counter this, NASCAR rules now require that the seat be attached, at several points, directly to the tubular structure that forms the roll cage, which is sometimes the only part of the car left intact after a crash.
The shape of the seat is important, too. Most of the seats found in NASCAR race cars wrap around the driver's rib cage. This provides some support during a crash, spreading the load out over the entire rib cage instead of letting it concentrate in a smaller point. Some newer seats wrap around the driver's shoulders as well, which provides better support because the shoulders are more durable than the rib cage.