Tesla crash: driver ignored warnings, investigators find

A man killed in a car crash last year while using the semi-autonomous driving system on his Tesla Model S kept his hands off the wheel for extended periods of time despite repeated audible warnings not to do so, according to the US National Transportation Safety Board, which released 500 pages of findings on the crash on Monday.

The Model S accident sparked a debate about the car company's partially autonomous driving tools. A witness told investigators it resulted in a cloud of white dust as the sedan ploughed underneath a tractor trailer  (See: Florida death puts big question-mark on Tesla autopilot )

''Just a white cloud, like just a big white explosion,'' said Terrence Mulligan, a witness who saw the impact and rushed to where the electric vehicle came to rest, told investigators with the National Transportation Safety Board.

The NTSB on Monday released hundreds of pages of technical reports on the 7 May 2016, accident. It hasn't yet concluded what caused the crash. The reports offered new details of the violent accident, but stopped short of clarifying why the driver didn't attempt to override the car's autonomous systems.

A Tesla spokeswoman referred inquiries to previous company statements about the crash. The company in June 2016 said its autopilot was engaged at the time of the crash and the company informed the US National Highway Traffic Safety Administration (NHTSA) about the accident immediately.

 ''Autopilot is by far the most advanced driver-assistance system on the road, but it does not turn a Tesla into an autonomous vehicle and does not allow the driver to abdicate responsibility,'' the company said.

Tesla has since unveiled improvements to Autopilot that temporarily prevents drivers from using the system if they don't respond to automated warnings to take control of their vehicle.

The NHTSA earlier this year found that the owner of the Tesla Model S sedan had ignored the manufacturer's warnings to maintain control even while using the driver-assist function. The agency said it found no defect in the vehicle and wouldn't issue a recall.

The NTSB probes only a handful of highway accidents each year in search of broad safety lessons. Unlike NHTSA, it can only issue recommendations.

The Tesla broadsided the truck, which was crossing the highway near Williston, Florida. The impact killed the Tesla driver, Joshua Brown, who had set the car to a speed of 74 miles an hour in a zone limited to 65 miles per hour.

There was no application of the brakes by either the driver or Tesla's automatic braking system before the impact, according to an analysis of the car's on board electronic data.

Brown, 40 and a former Navy SEAL, had been cited for speeding eight times between 2010 and 2015, according to Ohio records cited by the NTSB. He also had received a ticket for failing to obey a traffic signal, NTSB said.
The driver of the truck had had his license suspended five times between 1984 and 2013 for violations including speeding and failure to appear in court, according to NTSB.

The safety board's next step is to issue a report on the cause of the accident and any recommendations for preventing a re-occurrence.