Tesla's Autopilot semi-autonomous driving system was engaged during a fatal crash in March, when a Model 3 vehicle drove beneath a semitrailer in Florida, killing the Tesla driver, according to the National Transportation Safety Board.
The incident and the death of the driver, 50-year-old Jeremy Beren Banner, raised concerns about the effectiveness of Tesla's system.
Autopilot was engaged 10 seconds before the crash, and neither the system nor the driver stopped the vehicle, which was traveling at about 68 miles per hour at the moment of impact, federal investigators said. In addition, the vehicle did not detect the driver's hands on the wheel in the final 8 seconds before the crash, investigators said.
"Neither the preliminary data nor the videos indicate that the driver or the ADAS executed evasive maneuvers," the NTSB report said.
The roof of the Tesla was sheared off in the accident and the car came to rest in a median about 1,600 feet from where it struck the semitrailer. The driver of the semitrailer was uninjured.
In 2016, another crash in Florida occurred under similar circumstances.
In both instances, the driver was killed and the roof of the Tesla was torn off. Neither report assigned blame on the driver or the vehicle.
The Palo Alto-based automaker gave a statement to ABC News.
"Shortly following the accident, we informed the National Highway Traffic Safety Administration and the National Transportation Safety Board that the vehicle’s logs showed that Autopilot was first engaged by the driver just 10 seconds prior to the accident, and then the driver immediately removed his hands from the wheel. Autopilot had not been used at any other time during that drive," Tesla said.
"Tesla drivers have logged more than one billion miles with Autopilot engaged, and our data shows that, when used properly by an attentive driver who is prepared to take control at all times, drivers supported by Autopilot are safer than those operating without assistance," the statement said. "For the past three quarters we have released quarterly safety data directly from our vehicles which demonstrates that.”
The crash remains under investigation by the NTSB and the National Highway Traffic Safety Administration.
Tesla stock dropped 4.6% on Friday after the NTSB released its report.
Despite the name "Autopilot," Tesla's driver assistance technology does not make the vehicle autonomous. Tesla's website says the technology is "intended for use only with a fully attentive driver who has their hands on the wheel and is prepared to take over at any time."