Good Question: How Do Our Cars Protect Us?
MINNEAPOLIS (WCCO) -- When the weather gets bad, crash numbers on Minnesota roads pile up. Often times, these bad wrecks destroy cars, but the drivers and passengers inside survive.
So, how do our cars protect us? Good Question.
"Fifty years ago, cars were more designed so the car survived," says David Hallman, a forensic consultant engineer who investigates car crashes. "Basically, cars today are designed so that their entire job is to protect the operator and the people in the car."
Back in the early 1970s, more than 1000 Minnesotans died each year due to fatal crashes. Those numbers are now closer to 400 a year. Far better seat belt usage and airbags have made a huge difference in those statistics, but so has the construction of the cars.
Older cars were made with the body on the frame construction. With newer cars, the frame is part of the car.
"The frame was your protection, where now the whole car is your protection," says Hallman.
Hallman says cars are essentially designed to break out on the outside when they are hit. The car is stronger the closer to where the people sit inside. There are crush zones around the car that move, displace and absorb the energy from a crash.
"That's the whole idea for that energy to be absorbed in a way that you're not getting it," says Hallman.
The crush zones also slow the crash. Even a few dozen milliseconds makes a difference. The car will be hit with the same velocity, but the force on the person won't be as great because it will happen over a longer period of time.
These changes are also why it now costs so much more to repair a car that appears to have minor damage. There are pieces of foam and metal backers behind bumpers that are designed to bend, so when they take even a small hit, they will be damaged.
"These bumpers don't stand up in a crash but they do their job," says Hallman.
Finally, Hallman says the most important thing to remember when it comes to car crashes is seatbelts. Seatbelts keep people in the place they're supposed to be in the car when there's a crash. Airbags are also more effective, by design, when a person is belted in.