A 7,000-Pound Car Smashed Through a Guardrail. That’s Bad News for All of Us.

It’s a nightmare situation on a highway: Your car hits a patch of ice and starts to skid. Unable to regain control, you panic as you veer toward the roadway’s edge.

In emergencies like this, guardrails provide a failsafe. As explained in a federal memo, a guardrail will “deflect a vehicle back to the roadway [or] slow the vehicle down to a complete stop.” Your car will probably be damaged, but guardrails can prevent something much worse.

But some modern vehicles can instead smash through these guardrails, new research demonstrates, sending their passengers hurtling toward a ditch, cliff, or whatever is on the other side. The problem is that thousands of miles of guardrails installed alongside American highways were designed decades ago, when vehicles were much lighter than the behemoths that increasingly dominate the U.S. car market. And cars are only getting heavier: Bulkier electrified versions of big cars are poised to arrive in the years ahead. The risk of huge vehicles tearing through guardrails is yet another reason to expect American car bloat to augur an expensive, and dangerous, roadway future.