A Model S driver struck a tow hitch in the middle of a lane on Interstate 24 near Murfreesboro, Tennessee, damaging the car’s undercarriage and causing the fire, Dalya Qualls, a Tennessee Highway Patrol spokeswoman, said in an e-mail. The driver pulled the car over and was uninjured, Qualls said.
NHTSA declined to investigate a Model S fire in Washington state in October, the first such reported blaze, in which metal debris was involved.
“It appears there’s inadequate shielding on the bottom of these vehicles,” Ditlow said. “Road debris is a known hazard to the undercarriage of vehicles.”
The U.S. agency “will contact the local authorities who are looking into the incident to determine if there are vehicle safety implications that merit agency action,” Karen Aldana, a spokeswoman for NHTSA, said in an e-mail.
Liz Jarvis-Shean, a Tesla spokeswoman, declined to comment on Ditlow’s remarks and on whether the company needed to strengthen the aluminum casing that houses the 1,000-pound (454-kilogram) lithium-ion battery that powers the Model S.
“We have been in contact with the driver, who was not injured and believes the car saved his life,” Jarvis-Shean said in an earlier e-mail. “Our team is on its way to Tennessee to learn more about what happened in the accident. We will provide more information when we’re able to do so.”
Tesla, the best-performing automotive stock this year, has been under scrutiny as Chief Executive Officer Musk works to create the world’s biggest and most profitable seller of electric cars. Even with this week’s declines, Tesla shares have surged more than fourfold this year after reporting its first quarterly profits.
The Washington state Model S fire took place Oct. 1, and another occurred in Mexico in mid-October. NHTSA said Oct. 24 it found no evidence the first fire resulted from defects or violations of U.S. safety standards. The agency has said it doesn’t investigate vehicle accidents outside the U.S.
A possible fix for the Model S, priced from $70,000 to more than $100,000, “is not rocket science,” Ditlow said. “Probably the simplest task Tesla has is putting a strong steel shield on the bottom of the car.”