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Four people emerged nearly unscathed from a car crash off a 250-foot cliff.
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It’s very rare to survive such an accident, but not entirely unheard of, said one expert.
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Professor Jahan Rasty cited several Tesla safety features that likely helped.
People who survived driving off a 250-foot cliff were lucky to live — and it helped a lot to be in a Tesla, one expert told Insider.
Two adults and two children escaped with only minor injuries after plummeting from the rock face known as the Devil’s Slide, not far from San Francisco.
Dharmesh Patel, a 42-year-old Pasadena physician, was arrested on attempted murder charges after the incident. He was formally indicted on Monday.
San Mateo County District Attorney Steve Wagstaffe told Insider Tuesday that Neha Patel, his wife, told paramedics rescuing the family at the scene that she had intentionally run the car off the road.
Such a fall would likely be fatal in nearly all cases, according to Jahan Rasty, a forensic engineer who studies crashes.
Rasty, who is a professor of mechanical engineering at Texas Tech University, spoke to Insider about the physics of the crash and how Tesla’s safety features likely helped.
Fatal energy
Car accidents of any kind boil down to the transfer of energy. If too much energy from a moving car is suddenly directed into people’s bodies, they will die.
When the car comes to a screeching halt, that energy has to go somewhere, as Rasty explained. The safety design of the car is all about dissipating that energy away from the passengers.
One way is to strategically build the car so that it crumples on impact, expending the energy to bend the chassis. This process is called energy dissipation.
This photo shows a NASCAR crash where the crumpled design is doing its job:
They were lucky to roll before impact
No car is built with a huge drop in mind. Had the car fallen its full height without stopping, it’s very unlikely the passengers would have survived, Rasty said.
Rasty’s job is to determine what happened to a car by examining the wreckage and he described the probable events in this accident.
He estimated that the car went off the road at 77 miles per hour, fell about 200 feet, rolled onto the cliff several times, then dropped another 50 feet to land squarely on its tires.
“The car is totaled up, but the damage is pretty even all around,” he said of the pictures of the wreck.
Every time the car hit the side of the cliff, some energy was dissipated as a side panel crumbled away, he said. This meant that the energy was not all concentrated in one place.
“That’s really what saved them, the fact that the impact energy was distributed evenly around the car,” he said.
Had the nose gone first, the car would have had to absorb all that energy at once.
Not all cars are built equal
According to Rasty, they were very lucky to be in a Tesla.
Tesla roofs “are about 30 percent stronger in terms of impact resistance” than a regular car, Rasty said.
“So they can support about four times the weight of the car where the average requirement is three times the weight of the car.”
This means that the car was not likely to collapse in on itself, which is a risk every time a car rolls over.
Weight distribution also helped, she said.
A Tesla battery goes in the center of the car, unlike a gasoline car which usually has its heavy engine right in the front.
This means that the Tesla is less likely to nose-down and instead has a tendency to roll sideways.
Teslas also have a safety feature called a steel step frame, designed to redirect energy to the parts of the car that can handle it best.
“Being in that Tesla definitely improved their odds,” he said. “They’re pretty safe cars.”
Seat belts and car seats were also essential
The car can only protect the passengers if they stay inside the car during the crash, Rasty noted.
Without fastened seat belts and car seats for the children, they would have fared much worse.
Combined, Rasty said, these factors caused a seemingly fatal accident to become an unlikely survival story instead.
“Being in that Tesla definitely improved their odds,” Rasty said.
This story was updated on February 1, 2023, to reflect the latest developments in the case
Read the original article on Business Insider
