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Four people escaped nearly uninjured from a car crash off a 250-foot cliff.
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Surviving such an accident is very rare, but not entirely unheard of, an expert said.
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Professor Jahan Rasty cited several Tesla safety features that likely helped.
The people who survived by driving off a 250-foot cliff were lucky to live, and being in a Tesla helped a lot, an expert told Insider.
Two adults and two children escaped with minor injuries after plummeting off the rock known as Devil’s Slide, not far from San Francisco.
Dharmesh Patel, a 42-year-old physician from Pasadena, was arrested on attempted murder charges after the accident. He was indicted Monday.
San Mateo County District Attorney Steve Wagstaffe told Insider on Tuesday that Neha Patel, his wife, told paramedics who rescued the family at the scene that he had intentionally run the car off the road.
Such a fall would likely be fatal in almost all cases, according to Jahan Rasty, a forensic engineer who studies accidents.
Rasty, 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 come 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 an abrupt stop, that energy has to go somewhere, as Rasty explained. Car safety design is all about dissipating that energy away from passengers.
One way is to strategically build the car so that it crumples on impact, using the energy to bend the chassis. That process is called energy dissipation.
This photo shows a NASCAR accident where the warp design is doing its job:
They were lucky to roll before impact
No car is built with a huge, sheer drop in mind. If the car had fallen that far without stopping, it’s highly 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 likely events in this accident.
He estimated that the car went off the road at 77 miles per hour, fell about 200 feet, rolled off the cliff several times, and then fell another 50 feet to land on its tires.
“The car is totaled, but the damage is pretty even around it,” he said of images of the wreckage.
Every time the car hit the side of the cliff, some of the energy was dissipated when a side panel collapsed, 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.
If it had fallen nose first, the car would have had to absorb all of that energy at once.
All cars are not the same
According to Rasty, they were very lucky to be in a Tesla.
Tesla’s roofs “are about 30% stronger in terms of crashworthiness” than those of a normal 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.”
That means the car wasn’t likely to collapse on itself, which is a risk any time a car rolls over.
Weight distribution also helped, he said.
A Tesla battery goes in the middle of the car, unlike a gas car that usually has its heavy engine right in the front.
This means the Tesla is less likely to fall head-on and instead tends to roll sideways.
Teslas also have a safety feature called a stepped steel frame, which is designed to redirect energy to the parts of the car that can handle it best.
“Being in that Tesla definitely improved his odds,” he said. “They’re pretty safe cars.”
Seat belts and car seats were also essential
The car can only protect passengers if they stay inside the car during the crash, Rasty noted.
Without seat belts and child safety seats, they would have fared much worse.
Combined, Rasty said, those factors meant that a seemingly deadly crash turned into an unlikely survival story.
“Being in that Tesla definitely improved his 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
