Four people emerged almost unscathed from a car crash off a 250ft cliff.
Surviving such an accident is extremely rare, but not completely unheard of, an expert said.
Professor Jahan Rasty mentioned some Tesla safety features that probably helped.
Those who survived 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 only minor injuries after falling from the rock face known as Devil’s Slide, not far from San Francisco.
Dharmesh Patel, a 42-year-old Pasadena doctor, was arrested on charges of attempted murder after the crash. He was formally charged on Monday.
San Mateo County District Attorney Steve Wagstaffe told Insider on Tuesday that Neha Patel, his wife, told paramedics to rescue the family at the scene that he drove the car off the road on purpose.
Such a fall would likely be fatal in almost all cases, according to Jahan Rasty, a forensic engineer who studies crashes.
Rasty, who is a professor of mechanical engineering at Texas Tech University, talked Insider through the physics of the crash, and how Tesla’s safety features likely helped.
Car crashes of any kind come down to energy transfer. If too much energy from a moving car is suddenly directed into people’s bodies, they will die.
When the car stops suddenly, that energy has to go somewhere, as Rasty explained. Car safety design is all about dissipating that energy from the passengers.
One way is to strategically build the car so that it sinks on impact, using the energy to bend the chassis. That process is called energy dissipation.
This photo shows a NASCAR crash where the crumple design is doing its job:
They were lucky to roll before the impact
No car is built with a huge drop, including a big one. If the car had fallen that full height without stopping, there is little chance that the passengers would have lived, said Rasty.
Rasty’s job is to find out 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 onto the cliff several times, then fell another 50 feet to land square on its tires.
“The car is complete, but the damage is pretty uniform around it,” he said of the wreckage imagery.
Every time the car hits the side of the cliff, a bit of the energy dissipates when a side panel falls, he said. This meant that all the energy was not concentrated in one place.
“That is really what saved them, the fact that the energy of the impact was evenly distributed throughout, throughout the car,” he said.
If it fell nose first, the car would have to absorb all that energy at once.
Not all cars are built equal
According to Rasty, they were lucky to be in Tesla.
Tesla roofs are “about 30% stronger in terms of crash resistance” than a regular car, Rasty said.
“So they can support about four times the weight of the car when the average requirement is three times the weight of the car.”
This means that the car is unlikely to fall over on its own, which is a risk when a car passes by.
The weight distribution also helped, he said.
Tesla’s battery goes in the middle of the car, unlike a gas car which has its heavy engine right at the front.
This means that the Tesla is less likely to fall nose first and instead has a tendency to roll sideways.
Teslas also have a safety feature called a steel step frame, which is designed to redirect energy to the parts of the car that can best handle it.
“Tesla has definitely improved their odds,” he said. “They’re pretty safe cars.”
Seat belts and car seats were also required
The car can only protect the passengers if they stay inside the car during the accident, Rasty noted.
Without seat belts and car seats for the children, they would have fared much worse.
Combined, Rasty said, those factors meant that an apparently fatal accident turned into a hopeful story of survival.
“Tesla definitely improved their odds,” Rasty said.
This story was updated on 1 February 2023, to reflect the latest developments in the case
Read the original article on Business Insider