The man killed in a crash while using the autopilot function of a Tesla Model S electric vehicle posted a YouTube video a month before the fatal crash showing the technology saving him from another collision and wrote that he was "very impressed."
"Tessy did great. I have done a lot of testing with the sensors in the car and the software capabilities," Joshua Brown, 40, of Canton, Ohio, wrote on April 5 in comments posted with the 41-second video.
"I have always been impressed with the car, but I had not tested the car's side collision avoidance," he said. "I am VERY impressed. Excellent job Elon!"
Musk touted the video on Twitter on April 17.
Then on May 7, Brown, a former Navy Seal, was killed when his Tesla crashed into a tractor trailer in Williston, Fla.
Federal regulators said Thursday they had opened an investigation into the fatality, thought to be the first in the auto industry involving an autonomous driving feature.
The National Highway Traffic Safety Administration said its Office of Defects Investigation was conducting a preliminary evaluation of the autopilot function.
The agency is expected to issue guidelines for autonomous vehicles this month. Automakers do not need to have autonomous driving functions approved by NHTSA but must certify their vehicles meet safety standards.
Calling Brown's death "a tragic loss," Tesla said it was the first-known fatality involving its autopilot feature.
The technology, which is in public beta testing and must be activated by the driver, has been used in 130 million miles of driving without a fatality, the company said.
The crash took place at 3:40 p.m. May 7 on U.S. Route 27A during clear and dry conditions, according to the accident report from the Florida Highway Patrol.
Brown's vehicle was headed east when a tractor trailer driven by Frank Baressi of Palm Harbor, Fla., traveling in the opposite direction, made a left turn onto a side street.
The Tesla's roof hit the underside of the tractor trailer. The car skidded under the truck and off the road, plowing through two wire fences before crashing into a utility pole, the accident report said.
Brown was pronounced dead at the scene.
Baressi told the Associated Press that Brown was "playing 'Harry Potter' on the TV screen" in the car when the crash took place.
Sgt. Kim Montes, a spokeswoman for the Florida Highway Patrol, told The Times that a portable DVD player was found in the Tesla but said she did not know whether it had been in use.
"At the time of the impact, we don't know what the status of that DVD player was. Investigators are looking into it," she said.
"The roof was sheared off, and a lot of items were tossed around in the car," Montes said. "We may never know."
Baressi did not respond to a voicemail requesting comment.
Tesla said the truck's color and the bright sky led to the accident.
"Neither Autopilot nor the driver noticed the white side of the tractor trailer against a brightly lit sky, so the brake was not applied," Tesla said Thursday.
But Clarence Ditlow, executive director of the Center for Auto Safety, said Tesla's explanation didn't make sense.
"If you don't have a radar system on a car that can tell you there's a truck ahead of you, there's a problem," he said.
Ditlow said Tesla should issue a recall and disable the autopilot function until the NHTSA issues safety guidelines.
"The Tesla vehicles with autopilots are vehicles waiting for a crash to happen, and it did in Florida," he said.
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